Discussion:
Diesel APUs
(too old to reply)
c***@public.gmane.org
2008-04-05 21:45:23 UTC
Permalink
<<This is equivalent to just under 18.5% efficient for your generator
and 19.7% for his 8kWh figure. Either way, when you add in the
electric inefficiencies, it's definitely worse than a comparable gas
car.>>

We know EVs are fairly high in efficiency, but a diesel engine is
still better than a gas version - averaging 35% or more. A gallon of
diesel has 40kWh of energy, so that gives us 14kWh out the crankshaft
(at least in a car-sized engine). Even before conversion to
electricity, that means you are spending $0.25-0.30 per kWh! I've
tried the SVO route, and my time is worth more than the cost of the
fuel I saved. If anyone is going to be running an APU on their EV,
please take accurate measurements of input, output, and cost so we get
a baseline for discussion.
Mark Grasser
2008-04-05 21:52:45 UTC
Permalink
I'm unsure on how this gallon per hour is less efficient than a conventional
ICE. If it puts out 8 kwh and that equals a little over 10 hp, isn't that 10
hp able to push a small car at something around 45 mph? In my eyes that
equals 45 mpg. What am I missing?



Mark Grasser



-----Original Message-----
From: ev-bounces-UWgVIey+***@public.gmane.org [mailto:ev-bounces-UWgVIey+***@public.gmane.org] On Behalf
Of cowtown-***@public.gmane.org
Sent: Saturday, April 05, 2008 5:45 PM
To: ev-UWgVIey+***@public.gmane.org
Subject: Re: [EVDL] Diesel APUs

<<This is equivalent to just under 18.5% efficient for your generator
and 19.7% for his 8kWh figure. Either way, when you add in the
electric inefficiencies, it's definitely worse than a comparable gas
car.>>

We know EVs are fairly high in efficiency, but a diesel engine is
still better than a gas version - averaging 35% or more. A gallon of
diesel has 40kWh of energy, so that gives us 14kWh out the crankshaft
(at least in a car-sized engine). Even before conversion to
electricity, that means you are spending $0.25-0.30 per kWh! I've
tried the SVO route, and my time is worth more than the cost of the
fuel I saved. If anyone is going to be running an APU on their EV,
please take accurate measurements of input, output, and cost so we get
a baseline for discussion.

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Stephen West
2008-04-05 23:05:10 UTC
Permalink
> isn't that 10 hp able to push a small car at something around 45 mph?
> In my eyes that equals 45 mpg. What am I missing?

I think the EPA would disagree. They define driving cycles that try to
emulate typical urban and freeway driving patterns. That most certainly
includes stopping at traffic lights, climbing hills etc.

I have what I think of as a "small car" (though Tom may disagree :-),
currently weighing in at 2400 lbs including driver. Sure, it takes 6.5kW
_at_the_wheels_ to maintain 45mph on a perfectly flat smooth road. But roads
around these parts tend not to be flat, nor particularly smooth.

Steve
Mark Grasser
2008-04-06 00:25:47 UTC
Permalink
> isn't that 10 hp able to push a small car at something around 45 mph?
> In my eyes that equals 45 mpg. What am I missing?

> I think the EPA would disagree.

Well IMHO there is the EPA and then there is reality. I am thinking that if
this generator were of the "Long Ranger" type it would be maintaining the
drive batteries at a predetermined level and going up the hills the
batteries would help and going down the hill the drive batteries would get a
little extra charge kind of, well actually just like, my insight. This means
that everything averages out and the Car should be able to maintain that
8kwh speed.

Mark Grasser




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EVDL Administrator
2008-04-06 03:43:27 UTC
Permalink
On 5 Apr 2008 at 17:52, Mark Grasser wrote:

> If it puts out 8 kwh and that equals a little over 10 hp, isn't that 10
> hp able to push a small car at something around 45 mph? In my eyes that equals
> 45 mpg. What am I missing?

The fact that kWh does not convert to hp? The first is a unit of energy,
the second a unit of power.

David Roden - Akron, Ohio, USA
EVDL Administrator

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Mark Grasser
2008-04-06 17:01:11 UTC
Permalink
David,
So other then I missed kw vs kwh you don't have an explanation to back the
argument? I was serious, I would like to know why an 8kw generator
charging/powering a small EV can't get the equivalent of 45 mpg thus being
better than, or at least equal to, an equivalent car being powered by
petrol.

Mark Grasser



-----Original Message-----
From: ev-bounces-UWgVIey+***@public.gmane.org [mailto:ev-bounces-UWgVIey+***@public.gmane.org] On Behalf
Of EVDL Administrator
Sent: Saturday, April 05, 2008 11:43 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Diesel APUs

On 5 Apr 2008 at 17:52, Mark Grasser wrote:

> If it puts out 8 kwh and that equals a little over 10 hp, isn't that 10
> hp able to push a small car at something around 45 mph? In my eyes that
equals
> 45 mpg. What am I missing?

The fact that kWh does not convert to hp? The first is a unit of energy,
the second a unit of power.

David Roden - Akron, Ohio, USA
EVDL Administrator

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EVDL Information: http://www.evdl.org/help/
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Note: mail sent to "evpost" or "etpost" addresses will not
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email address from the webpage http://www.evdl.org/help/ .
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Robert MacDowell
2008-07-11 05:21:20 UTC
Permalink
This is really old, but I wanted to cry foul on a statement no one
challenged that is way past merely wrong.

Peter VanDerWal wrote:
> Because 8kw into an EV drivetrain (motor+controller) results in about 8 hp
> mechanical power out.
> 8kw will only move most EVs at about 40-45 mph. So you get 40-45mpg, but
> ONLY at 40-45 mph. There are diesel powered vehicles that get 45-50 mpg
> at 55-60 mph.
> The EXACT same Diesel engine from above would be able to propel the EXACT
> same vehicle at about 55-60 mph if it was connected directly to the
> transmission instead.
> Converting mechanical power to electrical power looses you 20-25% of the
> power/energy. Converting the electrical energy BACK into mechanical power
> looses you ANOTHER 20-25%. Total lost power/energy is between 35-45%.

Flat untrue. If it were true, every diesel-electric locomotive on the
planet would instantly explode in a ball of flames. A locomotive's
traction alternator is simply not capable of absorbing that kind of
energy -- it doesn't even have a cooling blower. Nor is the switchgear
cooled. The diode array only drops 1 volt on each side, so 2V on 600V.
That's 0.33%.

The efficiency of generator-switchgear-motor transmission is WHY it's
used instead of hydrostatic or mechanical drive. The others have been
tried, many times, and failed the "economical" test.

I can't tell you what generator loss should be, exactly, because it
depends entirely on sizing. Too small a generator will get hot. But if
you're losing 20% in the generator, you're doing something crazy wrong!


Robert
(end)

>> David,
>> So other then I missed kw vs kwh you don't have an explanation to back the
>> argument? I was serious, I would like to know why an 8kw generator
>> charging/powering a small EV can't get the equivalent of 45 mpg thus being
>> better than, or at least equal to, an equivalent car being powered by
>> petrol.
>>
>> Mark Grasser
>>
>>
>>
>> -----Original Message-----
>> From: ev-bounces-UWgVIey+***@public.gmane.org [mailto:ev-bounces-UWgVIey+***@public.gmane.org] On
>> Behalf
>> Of EVDL Administrator
>> Sent: Saturday, April 05, 2008 11:43 PM
>> To: Electric Vehicle Discussion List
>> Subject: Re: [EVDL] Diesel APUs
>>
>> On 5 Apr 2008 at 17:52, Mark Grasser wrote:
>>
>>> If it puts out 8 kwh and that equals a little over 10 hp, isn't that 10
>>> hp able to push a small car at something around 45 mph? In my eyes that
>> equals
>>> 45 mpg. What am I missing?
>> The fact that kWh does not convert to hp? The first is a unit of energy,
>> the second a unit of power.
>>
>> David Roden - Akron, Ohio, USA
>> EVDL Administrator
>>
>> = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
>> EVDL Information: http://www.evdl.org/help/
>> = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
>> Note: mail sent to "evpost" or "etpost" addresses will not
>> reach me. To send a private message, please obtain my
>> email address from the webpage http://www.evdl.org/help/ .
>> = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
>>
>>
>> _______________________________________________
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>> _______________________________________________
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>
>
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Lee Hart
2008-07-11 15:59:20 UTC
Permalink
Peter VanDerWal wrote:
>> Converting mechanical power to electrical power loses 20-25% of the
>> power. Converting the electrical energy BACK into mechanical power
>> loses ANOTHER 20-25%. Total lost power/energy is between 35-45%.

Robert MacDowell wrote:
> Flat untrue. If it were true, every diesel-electric locomotive on the
> planet would instantly explode in a ball of flames...

I think Peter is talking about small ICE-generator-battery-motor systems
like you find in a Prius.

A 10 HP electric motor or generator will have an efficiency around
80-90%. Running the ICE's power through a generator and motor thus
results in 64-81%. Knock off a few more percent for controllers. If
you're buffering the power through batteries, their efficiency takes
another 80-90%. All this give you something like 50% overall efficiency.

> The efficiency of generator-switchgear-motor transmission is WHY it's
> used instead of hydrostatic or mechanical drive. The others have been
> tried, many times, and failed the "economical" test.

The system in a diesel-electric locomotive is 100 times larger. A 1000
HP electric motor or generator is more like 95% efficient. Their
controllers are likewise slightly more efficient, and there are no
batteries to buffer the power, so no losses there (they use all the
power they generate immediately, without having to store it and recover
it later). Thus they can get an 85-90% overall efficiency -- that's
better than they could get with hydraulics or conventional transmissions.

--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
Robert MacDowell
2008-07-11 20:43:46 UTC
Permalink
Lee Hart wrote:
> Peter VanDerWal wrote:
>>> Converting mechanical power to electrical power loses 20-25% of the
>>> power. Converting the electrical energy BACK into mechanical power
>>> loses ANOTHER 20-25%. Total lost power/energy is between 35-45%.
>
> Robert MacDowell wrote:
>> Flat untrue. If it were true, every diesel-electric locomotive on the
>> planet would instantly explode in a ball of flames...
>
> I think Peter is talking about small ICE-generator-battery-motor systems
> like you find in a Prius.
>
> A 10 HP electric motor or generator will have an efficiency around
> 80-90%.

Can you explain why that is unavoidable?

> Running the ICE's power through a generator and motor thus
> results in 64-81%. Knock off a few more percent for controllers. If
> you're buffering the power through batteries, their efficiency takes
> another 80-90%. All this give you something like 50% overall efficiency.

As for the battery losses, that only applies partially. If the vehicle
is both in motion and generating, a fraction of the generated power will
go directly to from generator to drive motors. At freeway cruise this
will be the lion's share, I would think. That fraction doesn't suffer
the charge/discharge loss.

> > The efficiency of generator-switchgear-motor transmission is WHY it's
> > used instead of hydrostatic or mechanical drive. The others have been
> > tried, many times, and failed the "economical" test.
>
> The system in a diesel-electric locomotive is 100 times larger. A 1000
> HP electric motor or generator is more like 95% efficient.

But WHY? You're claiming this is a natural and inevitable result of
size. I claim sizing, i.e. the design choices made due to economic
circumstance. Ohm's Law knows no size.

You could build a locomotive whose generator is undersized - thinner
copper windings so higher resistance - and must operate near thermal
limits. I could see a 90% efficient generator, but it would need forced
cooling (another loss). Obviously it's not done because of economics.
The cost of the additional copper is trivial compared to the cost of the
additional fuel over a locomotive's lifetime given the locomotive's high
duty cycle.

By contrast, a Honda generator has both very low duty cycles and a
customer base mainly concerned with upfront costs; therefore using the
minimal amount of copper and letting it run hot is a reasonable design
decision. But I say you could also make one with enough copper to run
cool and efficient; it just wouldn't sell.

I could be wrong; convince me that the efficiency issues are innate to
the laws of physics.

Robert
redrocket
2008-07-11 20:47:10 UTC
Permalink
Hello!

I can't seem to find the company, maybe I don't have the spelling correct,
but there's a 1000amp controller made by Logitech? Where can I find some
info or contact info.

thanks

Marc
Gerald Wagner
2008-07-12 01:02:02 UTC
Permalink
It is Logisystems. If you want to buy one go to Grassrootsev.com

On Fri, Jul 11, 2008 at 4:47 PM, redrocket <redrocket-***@public.gmane.org> wrote:

> Hello!
>
> I can't seem to find the company, maybe I don't have the spelling correct,
> but there's a 1000amp controller made by Logitech? Where can I find some
> info or contact info.
>
> thanks
>
> Marc
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
redrocket
2008-07-12 02:00:00 UTC
Permalink
Greetings.

I'm not a programmer, but was thinking about a nice front end touch screen
computer in the car. The Apple Itouch runs Leopard OS 10.5. ($299) They just
recently opened the software development kit. This is what I was thinking.

realtime monitoring of rpms, volts, bms, amps, temp., (what else would be
good)?

You could see on the color display what ever data you wanted. and since it
has built in wifi, when you park it in the garage at home, you could access
all the data on your PC wirelessly.

What monitoring hardware, circuitry, would you need to measure, these
variables and then send them via USB to the Itouch?

Not bad for $300. Nice onboard computer, and you can still listen to your
favorite tunes, and youtube videos, as you wait for your batteries to charge
plugged into towns Christmas light outlet.:-)

Thanks

marc
Steven **
2008-07-12 02:59:30 UTC
Permalink
I had the same idea. But I'm planning to use the Neo Freerunner
(http://www.openmoko.com). It's a lot more hackable. It's $100 more,
but I also plan to use it as my primary phone. I don't think you'd
get the low-level access you need on an itouch.
If you're looking for something to leave in the car, I think you could
build a PC for cheaper than the itouch that would have all the
features you need and more. But all that may be precluded by your
"I'm not a programmer" statement. I think no matter which route you
go with, you're going to have a very steep learning curve.

-Steven

On Fri, Jul 11, 2008 at 9:00 PM, redrocket <redrocket-***@public.gmane.org> wrote:
> Greetings.
>
> I'm not a programmer, but was thinking about a nice front end touch screen
> computer in the car. The Apple Itouch runs Leopard OS 10.5. ($299) They just
> recently opened the software development kit. This is what I was thinking.
>
> realtime monitoring of rpms, volts, bms, amps, temp., (what else would be
> good)?
>
> You could see on the color display what ever data you wanted. and since it
> has built in wifi, when you park it in the garage at home, you could access
> all the data on your PC wirelessly.
>
> What monitoring hardware, circuitry, would you need to measure, these
> variables and then send them via USB to the Itouch?
>
> Not bad for $300. Nice onboard computer, and you can still listen to your
> favorite tunes, and youtube videos, as you wait for your batteries to charge
> plugged into towns Christmas light outlet.:-)
>
> Thanks
>
> marc
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
Peter VanDerWal
2008-07-11 23:40:41 UTC
Permalink
Well, if you want cheap...there is a lot of info on the web about
programming the GameBoy Advanced
They are less than $100 brand new and often can be found at garage sales
for $10 or so

Backlit color display, incredibly low power consumption, hackable, small
(so it won't clutter up your dash) what more could you want?

There are a ton of similar devices that could be used, though I'm not
aware of any other that is so cheap and readily available. Palm pilots
come close, but I don't think as many of them were sold and new ones cost
a lot more than a new GBA.

FWIW last year I bought a small linux computer with a 7" touch screen that
is designed for use in a car, as I recall it cost about $200 or so. Even
comes with a built in GPS system, media player and 20G hard drive.
They aren't made anymore (apparently the geniuses that built them didn't
think anyone would object to them naming it a "MacVision") but you might
be able to find a used one somewhere.


> I had the same idea. But I'm planning to use the Neo Freerunner
> (http://www.openmoko.com). It's a lot more hackable. It's $100 more,
> but I also plan to use it as my primary phone. I don't think you'd
> get the low-level access you need on an itouch.
> If you're looking for something to leave in the car, I think you could
> build a PC for cheaper than the itouch that would have all the
> features you need and more. But all that may be precluded by your
> "I'm not a programmer" statement. I think no matter which route you
> go with, you're going to have a very steep learning curve.
>
> -Steven
>
> On Fri, Jul 11, 2008 at 9:00 PM, redrocket <redrocket-***@public.gmane.org> wrote:
>> Greetings.
>>
>> I'm not a programmer, but was thinking about a nice front end touch
>> screen
>> computer in the car. The Apple Itouch runs Leopard OS 10.5. ($299) They
>> just
>> recently opened the software development kit. This is what I was
>> thinking.
>>
>> realtime monitoring of rpms, volts, bms, amps, temp., (what else would
>> be
>> good)?
>>
>> You could see on the color display what ever data you wanted. and since
>> it
>> has built in wifi, when you park it in the garage at home, you could
>> access
>> all the data on your PC wirelessly.
>>
>> What monitoring hardware, circuitry, would you need to measure, these
>> variables and then send them via USB to the Itouch?
>>
>> Not bad for $300. Nice onboard computer, and you can still listen to
>> your
>> favorite tunes, and youtube videos, as you wait for your batteries to
>> charge
>> plugged into towns Christmas light outlet.:-)
>>
>> Thanks
>>
>> marc
>>
>>
>> _______________________________________________
>> For general EVDL support, see http://evdl.org/help/
>> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>>
>>
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
Doug Weathers
2008-07-12 08:31:27 UTC
Permalink
On Jul 11, 2008, at 8:00 PM, redrocket wrote:

> Greetings.
>
> I'm not a programmer, but was thinking about a nice front end touch
> screen
> computer in the car.

That's a good idea! The iPhone would also work, and if you already
have one you don't need to buy the iPod touch.

> realtime monitoring of rpms, volts, bms, amps, temp., (what else
> would be
> good)?

Navigation? The iPod touch and the iPhone both have a location
service that has a Google back end. The new iPhone has assisted GPS
so should be able to act as a GPS navigation device to some extent.

I know, with the limited range of the usual EV a navigation system is
kind of silly. But it's probably doable.

The location service could also be used to figure out how many miles
you've travelled, and knowing the time it took you can figure an
average speed. Knowing the volts at a particular amp draw should let
you gauge the state of charge of your pack, so you can now figure out
how many miles you have left to go at your average speed. A really
cool feature would be to draw a range radius on the map. Add the map
from www.evchargermaps.com and you can see which recharge points you
can reach!

There's no end to the possibilities, really. This email is full of
brainstormed ideas that haven't been thought out.

> You could see on the color display what ever data you wanted.

Yes, and it has that brilliant touch interface.

> and since it
> has built in wifi, when you park it in the garage at home, you could
> access
> all the data on your PC wirelessly.

I think you've got it backwards. Instead of making the iPod or iPhone
monitor the car directly (which would require hardware that Apple
doesn't include), I'd use it as a front end to a car computer that
stays in the car and monitors and controls things. (Also, I'd never
leave my iPod in the car - it could get stolen, and besides I'd want
to be playing with it all the time! :) The iPod/iPhone would talk to
the car computer with WiFi. The car computer would have a web server
in it. You'd program the iPod/iPhone interface with the original Web
2.0 technologies they released it with on day one - no need for the
new SDK.

Your laptop could also talk to the car computer, if you need more
screen or want to do some keyboarding. And when you pull into your
garage, the car computer can connect to your house wireless network.
Now your home computer(s) can talk to it (so you can check on your
charger and batteries remotely), and the car computer can do things
like email log files to you so the car doesn't need a lot of storage
on board, or it could download the current price of electricity and
gasoline from the Internet and compute a running total of your cents
per mile.

> What monitoring hardware, circuitry, would you need to measure, these
> variables and then send them via USB to the Itouch?

If I were to do it today I'd probably use an Arduino with a WiFi
expansion card and the web server library.

<http://www.arduino.cc/>

Check the Instructables website for projects using the Arduino. <http://www.instructables.com
>

There are probably dozens of choices for the car computer, with wide
ranges of price and capability.

The Arduino has lots of sensor inputs and outputs. Use it to gather
data from the Zilla, or your PakTrakr, or your Brusa charger and
interpret and display it on the iPod. Use the outputs to control
features like the Zilla's valet mode, or to set parameters on the fly
with a MultiTouch GUI. Unlock your doors, and have them automatically
lock when your iPod goes out of range. Add features to your car if
they aren't already there - auto high beams (photocell sensor), wiper
delay, dome light delay.

> Not bad for $300. Nice onboard computer, and you can still listen to
> your
> favorite tunes, and youtube videos, as you wait for your batteries
> to charge
> plugged into towns Christmas light outlet.:-)

And if you upgraded to the new 3G iPhone, keep the old one and use it
for your EV dashboard!

>
>
> Thanks
>
> marc

--
Doug Weathers
Las Cruces, NM, USA
<http://www.gdunge.com/>
Peter VanDerWal
2008-07-12 08:33:43 UTC
Permalink
>> has built in wifi, when you park it in the garage at home, you could
>> access
>> all the data on your PC wirelessly.
>
> I think you've got it backwards. Instead of making the iPod or iPhone
> monitor the car directly (which would require hardware that Apple
> doesn't include), I'd use it as a front end to a car computer that
> stays in the car and monitors and controls things.
> leave my iPod in the car - it could get stolen, and besides I'd want
> to be playing with it all the time! :) The iPod/iPhone would talk to
> the car computer with WiFi. The car computer would have a web server
> in it. You'd program the iPod/iPhone interface with the original Web
> 2.0 technologies they released it with on day one - no need for the
> new SDK.

Of course (Dooh!), excellent idea. You could even use any of the hundreds
of other handheld wifi capable units. Nokia N800 etc.

This definitely (in my mind) makes one of the Alix boards a top contender
for the carputer.
Doug Weathers
2008-07-14 05:35:45 UTC
Permalink
On Jul 12, 2008, at 2:33 AM, Peter VanDerWal wrote:

> This definitely (in my mind) makes one of the Alix boards a top
> contender
> for the carputer.

The ALIX 3C plus that waterproof aluminum enclosure looks pretty
spiffy, all right.

But how would you connect it to the car? Some kind of USB DAC module,
wired up through the enclosure's Ethernet connection?

--
Doug Weathers
Las Cruces, NM, USA
http://www.gdunge.com/
Lee Hart
2008-07-12 17:39:09 UTC
Permalink
Doug Weathers wrote:
redrocket wrote:
>> thinking about a nice front end touch screen computer in the car.

I know touch screens are a popular idea; but are you sure that's what
you want the driver to be using? They require a significant amount of
time with your eyes off the road.

Our Toyota Prius has a touchscreen. I find it very distracting, and
almost dangerous to use while driving.

> I know, with the limited range of the usual EV a navigation system is
> kind of silly. But it's probably doable.

Actually, it can be handy. My old ComutaVan could barely do 55 mph, so
freeway use was only safe during "rush hour" when the actual speeds were
very slow. So, I normally used side roads and residential streets. A
good NAV system could be a big help.

>> and since it has built in wifi, when you park it in the garage at home,
>> you could access all the data on your PC wirelessly.

That's a useful feature.

>> What monitoring hardware, circuitry, would you need to measure, these
>> variables and then send them via USB to the Itouch?

Perhaps the most straightforward method is to get a multimeter with
serial USB or RS-232 interface. It can be set to measure almost anything.

> There are probably dozens of choices for the car computer, with wide
> ranges of price and capability.

Yes. The big challenge to find something that will actually survive in
an automotive environment. If you live in a place that doesn't have
weather, lots of indoor electronics will do. But if they have to contend
with extreme temperatures, condensation, bugs, etc. it will be more
difficult.

--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
Jeff Miller
2008-07-12 18:54:53 UTC
Permalink
I can speak to the computer in a car discussion and durability. I have had
a PC in my car since August of 2004. What have I learned in four years of
constant usage. Computers are more durable than most people give them
credit for. I am using a full ATX mainboard with an Athlon 64 Socket 754
Mobile CPU. Officially an MT-34 which dissapates 25watts. (for the PC
knowledgable I did an upgrade two years ago) It is mounted in a 4U
rackmountable chassis. The rackmounted chassis is mounted in a rack with
sliders in my trunk. It has been really good. It runs directly off of 12V
via a ATX power supply with big 12V screw terminals. I think the PSU can
support anything up to 48 volts but that isn't available in my old fashioned
ICE Grand Marquis. The monitor has been a real suprise. I am using a CTX
(generic) 15 inch LCD panel up front in the car and since it came with a 12V
brick I just cut the cord and wired it to run off of the computer PSU 12V
power. I have a USB hub under my seat and it is powered off of the 5V of
the computer. The harddrive is mounted on edge so bumps won't cause the
heads to hit the platter. With this system I have lived in Cincinnati,
Indianapolis, and Kansas City. It has lived outdoors and has been garaged.
Heat was an issue early on but I solved that some time ago without anything
exotic.

It is used anytime my car is. It is my car stereo and uses the optical
(Toslink) out to the car audio system to feed music. I don't have a
traditional car stereo. It runs Windows and I have a monster Wifi ant. on
the trunk for browsing the web. It also uses Garmin Mobile PC for
navigation along with the GPS18 USB receiver (which is externally mounted
via its integrated magnet).

I have wiring run so if I want to I can tie the carpc into the ODB module
connector but have never been quite that motivated. I did it back before
much of the nice stuff that is available today. The Via Epia platforms use
10 or so watts and can run direct off of 12V in a very small box.

So four years and counting. I have so far killed one DVDrom Drive. I think
the coldest the system has been when I fired it up was last winter after a
LONG day of work I went in to BIOS to check the temp and it displayed -10F.
Booted fine and listended to music all the way home. The LCD panel is
usually a little dim and slow but to be honest I never thought the LCD would
last four years.

-----Original Message-----
From: Lee Hart [mailto:leeahart-***@public.gmane.org]
Sent: Saturday, July 12, 2008 11:39 AM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Volts, Amps and an iPod touch computer


Doug Weathers wrote:
redrocket wrote:
>> thinking about a nice front end touch screen computer in the car.

I know touch screens are a popular idea; but are you sure that's what
you want the driver to be using? They require a significant amount of
time with your eyes off the road.

Our Toyota Prius has a touchscreen. I find it very distracting, and
almost dangerous to use while driving.

> I know, with the limited range of the usual EV a navigation system is
> kind of silly. But it's probably doable.

Actually, it can be handy. My old ComutaVan could barely do 55 mph, so
freeway use was only safe during "rush hour" when the actual speeds were
very slow. So, I normally used side roads and residential streets. A
good NAV system could be a big help.

>> and since it has built in wifi, when you park it in the garage at home,
>> you could access all the data on your PC wirelessly.

That's a useful feature.

>> What monitoring hardware, circuitry, would you need to measure, these
>> variables and then send them via USB to the Itouch?

Perhaps the most straightforward method is to get a multimeter with
serial USB or RS-232 interface. It can be set to measure almost anything.

> There are probably dozens of choices for the car computer, with wide
> ranges of price and capability.

Yes. The big challenge to find something that will actually survive in
an automotive environment. If you live in a place that doesn't have
weather, lots of indoor electronics will do. But if they have to contend
with extreme temperatures, condensation, bugs, etc. it will be more
difficult.

--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net


_______________________________________________
For general EVDL support, see http://evdl.org/help/
For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
Lee Hart
2008-07-12 20:47:04 UTC
Permalink
Jeff Miller wrote:
> I can speak to the computer in a car discussion and durability. I
> have had a PC in my car since August of 2004. What have I learned in
> four years of constant usage. Computers are more durable than most
> people give them credit for...

I think it's a question of playing the odds. Do you feel lucky? :-)

A particular piece of equipment might have 1 chance in 1000 of failing
per year when used indoors, but 1 in 100 if used outdoors in a car. Now
if it's just you, even that 1%/year failure rate is pretty good odds --
you might as well do it.

But suppose you're a manufacturer (or giving advice on some mailing list
) :-). If 1000 people do it, a 1%/year failure rate means 10 failures
per year, or almost 1 a month. These folks will be mad! They will tell
their friends, and complain online about your shoddy products or bad advice.

There are a lot of things I might do myself, to save a buck or because
it's expedient, or just to see what happens. But I am much more
conservative in what I advise others to do. I don't know their situation
well enough to judge what is "good enough" versus foolhardy.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
Jeff Miller
2008-07-13 02:31:05 UTC
Permalink
Fair enough
So don't install a desktop PC in your car unless you really know what you
are getting yourself in to.

When I put it together I figured it would be a serious parts hog requiring
routine replacement pieces but what I have found is just the opposite.
There are certain precautions to take and number 1 is make sure it is
absolutely mechanically coupled to the car, unless you have some
unbelieveable exotic computer suspension system, you must firmly fix it to
the car so it doesn't bounce harder than the car. Put filters on the inlets
to keep the dust down. Use laptop or low power processors. Laptop
processors are usually rated to 170F or there abouts. Laptops are a pretty
bad idea unless you buy a Toughbook. In Phoenix your interior might get to
170 but your trunk probably doesn't unless it has windows. Don't use a
black car (I do have a black car but doing it all over again I wouldn't)
they get even hotter. Tint the back most windows to limit the amount of
solar energy going into the car and hence the computer. Use a sun shade.
Don't use exotic cooling. Water cooling gets hot and stays that way. Freon
or Peltier cooling could easily cause condensation even if the normal
precautions are taken. Use the least powerful computer you can to get the
job done.

My machine is overkill, but that is the way I am, but the Laptop CPU makes a
huge difference in its ability to operate in the car. It has a large
heatsink on it too.

Also realize I don't live where the roads are especially rough. I also
drive a Grand Marquis which is softer than most. Those two factors limit
the max shock my equipment sees day in and day out. Oh and I have driven
53,000 miles in those 4 years since installing the computer.

I will also say that in the past month or so I have started to experience a
sharp rise in reboots caused by the rougher pavement so I will be tracing
that back to the failing component. The last time this happened I had a
DVDRom drive that was failing on rough pavement and locking the PC up. As
my PC has two I just disconnected the extra however the second one may be
the current problem part. Only time will tell as I trouble shoot it.

To your point Lee I would tell almost anyone who watches TV that knoppmyth
(MythTV packaged into a distro) is an awesome DVR package and if they want
to try it I will help them set it up but I have never helped anyone else
install a computer in a car. I would consider my setup to be pretty close
to ideal for me! My wife doesn't like it though. She does like Knoppmyth.

Back to auto PC stuff

PC's designed for cars. Most of them look like car audio amplifiers.
http://www.mini-box.com/s.nl/sc.8/category.101/.f

Mini boards with low power
http://www.mini-box.com/VERSA-3-x-10-100-LAN-Port-Daughterboard?sc=8&categor
y=20

Cool mini power supply
http://www.mini-box.com/s.nl/it.A/id.417/.f;jsessionid=0a010c441f439ff512f3d
a164716ae53fdbce4908663.e3eTa3aSaxmTe34Pa38Ta38LbNb0?sc=8&category=13

There are plenty of solutions and other people selling them. The above site
has been around doing mobile stuff for quite some time but I have never
actually purchased anything there.

Jeff


-----Original Message-----
From: Lee Hart [mailto:leeahart-***@public.gmane.org]
Sent: Saturday, July 12, 2008 2:47 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Volts, Amps and an iPod touch computer


Jeff Miller wrote:
> I can speak to the computer in a car discussion and durability. I
> have had a PC in my car since August of 2004. What have I learned in
> four years of constant usage. Computers are more durable than most
> people give them credit for...

I think it's a question of playing the odds. Do you feel lucky? :-)

A particular piece of equipment might have 1 chance in 1000 of failing
per year when used indoors, but 1 in 100 if used outdoors in a car. Now
if it's just you, even that 1%/year failure rate is pretty good odds --
you might as well do it.

But suppose you're a manufacturer (or giving advice on some mailing list
) :-). If 1000 people do it, a 1%/year failure rate means 10 failures
per year, or almost 1 a month. These folks will be mad! They will tell
their friends, and complain online about your shoddy products or bad advice.

There are a lot of things I might do myself, to save a buck or because
it's expedient, or just to see what happens. But I am much more
conservative in what I advise others to do. I don't know their situation
well enough to judge what is "good enough" versus foolhardy.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net


_______________________________________________
For general EVDL support, see http://evdl.org/help/
For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
Bill Dennis
2008-07-13 03:45:24 UTC
Permalink
I usually don't post big messages, but today was such a good day, I'm
hoping you'll put up with my gushing.

I drove the car down to Big-O tires today to have the alignment done and
to have the brakes and CV joints checked. My first reward was the tech
who drove the car into the bay, who kept saying, "This is so cool!" The
bigger reward came shortly afterward, when they checked the front
brakes. Both calipers were frozen tight against the wheel. So that
could explain why the car was struggling so hard to make it uphill.
When the brake job was finished, I drove the car down the block to the
inspection station--where it passed! The technician was so interested
in the EV that had me come into the bay and show him everything about
the car. It's really amazing to see the look on people's faces when
they step on the accelerator, and the car takes off without any engine
noise.

Next came the ride home, and I was fretting. It was an 1800 ft climb,
uphill almost all the way, with that last steep stretch at the end that
gave the car so much trouble the day before. This time, though, I was
able to maintain 25 to 35 mph, never sagging the voltage below 100V.
And that was while pulling about 100A. ThunderSky recommends a .3C max
discharge rate for their LCP cells, and they were right on the money.
100A is about .35C. I even had the car on a short stretch of
interstate, where I took it up to 60 mph at about 65A.

Total trip was 26.8 miles, and the EVision reports 25Ah and 4Kwh used,
today's and yesterday's trips combined. That seems almost too good to
be true, so I'm going to hook up the laptop to EVision tomorrow and make
sure the configuration still looks good. Voltage, by the way, jumped
back up to 131V once the car was parked back in the garage. It had
started at 138V this morning.

The only downside was that the air temperature reached over 35 Celsius
today, and the car sat out in the sunlight for 2 hours while I wanted
for the inspection. By the time I got home, the motor was really hot,
and the cells had climbed to 45 Celsius. I'd been hoping that the car's
being a convertible, the open air flowing through the battery enclosure
(vented intake behind the seats and vented out into the truck) would be
enough to keep them cool. But I think I should probably put fans in the
truck to actively pull air through, plus add a beefy blower to the motor
as well.

So, Roland, what's that good blower you have on your motor? And,
anyone, what are good fans to pull air through the battery enclosure?

Thanks again for everyone's help. And, if you've gotten this far,
thanks for listening to my bubbling.

Bill Dennis


P.S. Big-O tires had no problem working on the car--except there was
one thing they wouldn't do: bleed the brake lines. When I told them
that I'd replaced the power brakes with a non-power cylinder, they said
that this made it non-factory equipment, and they wouldn't touch it.
Lee Hart
2008-07-13 17:20:59 UTC
Permalink
Jeff Miller wrote:
> Fair enough. So don't install a desktop PC in your car unless you really
> know what you are getting yourself into...
>
> My machine is overkill, but that is the way I am, but the Laptop CPU
> makes a huge difference in its ability to operate in the car. It has a
> large heatsink on it too.
>
> PC's designed for cars. Most of them look like car audio amplifiers.
> http://www.mini-box.com/s.nl/sc.8/category.101/.f

Excellent advice, Jeff. I hadn't realized you were using something more
rugged, or that there were companies packaging PCs specifically to be
used in a car. I was addressing the cheapskate types that might try
putting a random cheap PC in their car.

--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
Doug Weathers
2008-07-14 05:39:58 UTC
Permalink
On Jul 12, 2008, at 11:39 AM, Lee Hart wrote:

> Doug Weathers wrote:
> redrocket wrote:
>>> thinking about a nice front end touch screen computer in the car.
>
> I know touch screens are a popular idea; but are you sure that's what
> you want the driver to be using? They require a significant amount of
> time with your eyes off the road.

Agreed. In my mind, the screen will have the most often used info
displayed and won't have flashy animations or demand to be regularly
fondled. Something like the EV Dash. You'd only need to touch it if
you wanted to do something other than have it act as a digital car
dashboard. Examples would be: playing with the audio (which could be
offloaded to any of several available iPod car interfaces), answering a
phone call (ditto), email and web browsing, changing Zilla settings,
navigation system. Mostly stuff you should only do with the car
stopped.

> Our Toyota Prius has a touchscreen. I find it very distracting, and
> almost dangerous to use while driving.

IMHO the canonical example of a bad car interface! One of the reasons
I don't own a Prius.

>> I know, with the limited range of the usual EV a navigation system is
>> kind of silly. But it's probably doable.
>
> Actually, it can be handy. My old ComutaVan could barely do 55 mph, so
> freeway use was only safe during "rush hour" when the actual speeds
> were
> very slow. So, I normally used side roads and residential streets. A
> good NAV system could be a big help.

Hadn't thought of that - good point.

>>> What monitoring hardware, circuitry, would you need to measure, these
>>> variables and then send them via USB to the Itouch?
>
> Perhaps the most straightforward method is to get a multimeter with
> serial USB or RS-232 interface. It can be set to measure almost
> anything.

But if you need to measure more than one thing (say, pack voltage AND
battery amps), you still need to be able to have the car computer
switch the meter's inputs to whatever signals you require. If you're
going to have a computer-controlled board full of relays, you might as
well just use a microcontroller with a bunch of inputs, right?

Perhaps the meter will give better accuracy, or will make it easier to
measure the signal without a lot of external components to condition
the signal for the microcontroller? Or be sturdier than an Arduino
board?

--
Doug Weathers
Las Cruces, NM, USA
http://www.gdunge.com/
Steven **
2008-07-14 02:19:49 UTC
Permalink
Thanks for the reminder on Arduino. I actually had that site
bookmarked on del.icio.us but had completely forgot about it. The
Diecimila looks perfect for my needs and is only $35 from SparkFun
Electronics. It can be powered off its USB port, which the Freerunner
can provide (we'll see how long it can provide power to the Diecimilia
before completely draining its battery).

It looks like the analog inputs' resolutions are 1.07 mV at the
finest. Might be able to get a finer resolution with a lower external
voltage reference. Failing that, the board supports I2C. I know
there are tons of I2C chips that could give high resolution voltage
readings in the sub-mV range.

-Steven

On Sat, Jul 12, 2008 at 3:31 AM, Doug Weathers <dougw-***@public.gmane.org> wrote:
> If I were to do it today I'd probably use an Arduino with a WiFi
> expansion card and the web server library.
>
> <http://www.arduino.cc/>
Robert Brown
2008-07-12 15:38:01 UTC
Permalink
redrocket wrote:
> Greetings.
>
> I'm not a programmer, but was thinking about a nice front end touch screen
> computer in the car. The Apple Itouch runs Leopard OS 10.5. ($299) They just
> recently opened the software development kit. This is what I was thinking.
>
> realtime monitoring of rpms, volts, bms, amps, temp., (what else would be
> good)?
>
> You could see on the color display what ever data you wanted. and since it
> has built in wifi, when you park it in the garage at home, you could access
> all the data on your PC wirelessly.
>
> What monitoring hardware, circuitry, would you need to measure, these
> variables and then send them via USB to the Itouch?
>
> Not bad for $300. Nice onboard computer, and you can still listen to your
> favorite tunes, and youtube videos, as you wait for your batteries to charge
> plugged into towns Christmas light outlet.:-)
>
> Thanks
>
> marc
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
>
>
I'm actually surprised that there isn't (or has there been?) more
interest in this topic. Seems as though the on board PC would be an
ideal medium to capture, and relatr all of the data - voltages, amp use,
mileage, with all manor of pie charts and graphs.
I'll be watching for it!
Bob
Marty Mercer
2008-07-12 02:36:20 UTC
Permalink
Since we're asking about controllers. Why the long lead time for
controllers? Whats the deal.....

On Fri, Jul 11, 2008 at 6:02 PM, Gerald Wagner <glwagner72-***@public.gmane.org> wrote:

> It is Logisystems. If you want to buy one go to Grassrootsev.com
>
> On Fri, Jul 11, 2008 at 4:47 PM, redrocket <redrocket-***@public.gmane.org> wrote:
>
> > Hello!
> >
> > I can't seem to find the company, maybe I don't have the spelling
> correct,
> > but there's a 1000amp controller made by Logitech? Where can I find some
> > info or contact info.
> >
> > thanks
> >
> > Marc
> >
> >
> > _______________________________________________
> > For general EVDL support, see http://evdl.org/help/
> > For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
> >
> >
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>


--
Marty Mercer
Sacramento, CA
patrick DonEgan
2008-07-13 03:42:16 UTC
Permalink
Hand made.... low volume..... they also test them.....
And we are still waiting for Apple to make one ;)



On Fri, Jul 11, 2008 at 4:36 PM, Marty Mercer <m2megagroup-***@public.gmane.org> wrote:

> Since we're asking about controllers. Why the long lead time for
> controllers? Whats the deal.....
>
> On Fri, Jul 11, 2008 at 6:02 PM, Gerald Wagner <glwagner72-***@public.gmane.org>
> wrote:
>
> > It is Logisystems. If you want to buy one go to Grassrootsev.com
> >
> > On Fri, Jul 11, 2008 at 4:47 PM, redrocket <redrocket-***@public.gmane.org> wrote:
> >
> > > Hello!
> > >
> > > I can't seem to find the company, maybe I don't have the spelling
> > correct,
> > > but there's a 1000amp controller made by Logitech? Where can I find
> some
> > > info or contact info.
> > >
> > > thanks
> > >
> > > Marc
> > >
> > >
> > > _______________________________________________
> > > For general EVDL support, see http://evdl.org/help/
> > > For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
> > >
> > >
> >
> > _______________________________________________
> > For general EVDL support, see http://evdl.org/help/
> > For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
> >
> >
>
>
> --
> Marty Mercer
> Sacramento, CA
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>


--
Patrick Ira Donegan
TigerBody Electric Vehicles
Lee Hart
2008-07-12 16:10:42 UTC
Permalink
Robert MacDowell wrote:
> Can you explain why that is unavoidable?

> As for the battery losses, that only applies partially. If the vehicle
> is both in motion and generating, a fraction of the generated power will
> go directly to from generator to drive motors. At freeway cruise this
> will be the lion's share, I would think. That fraction doesn't suffer
> the charge/discharge loss.

You are correct; however, the system will takes this opportunity to
fully charge the battery. Charging a battery from 80% to 100% state of
charge is its least efficient region. So, while only part of the
generator's power is going to the batteries, this part is very lossy.

Note that the Prius deliberately tries to avoid charging its pack above
80% SOC, just to avoid this loss. But with the pack at 80% SOC, as soon
as you slow down for a car in front of you or go down a hill, the excess
power *does* go into the battery. Due to the battery's inefficiency,
much of it gets converted to heat.

>> A 10 HP electric motor or generator will have an efficiency around
>> 80-90%. The system in a diesel-electric locomotive is 100 times larger.
>> A 1000 HP electric motor or generator is more like 95% efficient.

> But WHY? You're claiming this is a natural and inevitable result of
> size... Ohm's Law knows no size.

It's a long explanation, and one I've posted before (see if you can find
it in the archives). It requires that you know something about
electrical, magnetic, and mechanical losses.

Very roughly speaking... if you double the size of a particular motor
design, the losses roughly double (I^2R, magnetic, friction, windage,
etc.). But the horsepower you can get out of it goes up as the square
(because the surface area of the rotor-stator gap quadruples). Thus you
have half the loss per horsepower; a 90% efficient 10 HP motor becomes a
95% efficient 40 HP motor.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
Neon John
2008-07-12 08:29:14 UTC
Permalink
On Fri, 11 Jul 2008 10:59:20 -0500, Lee Hart <leeahart-***@public.gmane.org> wrote:


>The system in a diesel-electric locomotive is 100 times larger. A 1000
>HP electric motor or generator is more like 95% efficient. Their
>controllers are likewise slightly more efficient, and there are no
>batteries to buffer the power, so no losses there (they use all the
>power they generate immediately, without having to store it and recover
>it later). Thus they can get an 85-90% overall efficiency -- that's
>better than they could get with hydraulics or conventional transmissions.

I'd be afraid to even guess at the efficiency but the 1000 hp switch engine
that I ran for TVA for a couple of years definitely was NOT highly efficient.
It had two truck sets with two 600 volt DC motors on each truck. Each motor
drove the axle through what looked like about a 3:1 gear reduction. Each
truck set was cooled by a very high powered, high velocity blower that
supplied air from the engine compartment to the trucks through a flex duct.
Each blower was something like 5 HP. Another large blower cooled the
brush-type DC generator direct-coupled to the engine. 1000 HP at 750 RPM -
torque monster :-)

According to folks who knew a LOT more about it than I did, the grade coming
off the Southern line in Soddy-Daisy and leading to the Sequoyah Nuclear Plant
was the third steepest railroad grade in the country. In any event, a full
load up that grade was 4 or 5 open top cars loaded with pre-fabricated steel
structures.

One afternoon I was pulling a full load of steel to the plant when one of the
ducts came loose. The result was that the truck motors overheated in minutes
sufficient to catch on fire. No harm done, apparently just oil burning off,
for after I put the fire out with a CO2 fire extinguisher and slipped the duct
back in place, I continued on up the hill.

With that kind of heat being dissipated in the motors, the drivetrain could
not have been very efficient.

I bet that modern hydraulics could compete with that system. I do know that
many pieces of heavy equipment now have pure hydraulic drives. The engine
spins a hydraulic pump and the fluid operates everything including the tracks
or wheels.

It's interesting that even before this last fuel price run-up, there began a
big move to shift heavy equipment over to electric grid power whenever
possible. Bobcat makes an electric skid-steer. My friend at the scrap metal
yard just ordered one. Yep, it trails an umbilical behind it. Not battery
powered.

He's about to order a large electric track-hoe to replace the diesel-powered
one that he has now. They use over 1000 gallons of diesel a week so even with
demand charges, the payback will be rapid.

John

--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
Okay, okay, I'll take it back ... UNfuck you!
Lee Hart
2008-07-12 17:23:38 UTC
Permalink
Neon John wrote:
> I'd be afraid to even guess at the efficiency but the 1000 hp switch
> engine that I ran for TVA for a couple of years definitely was NOT
> highly efficient... Each truck set was cooled by a very high
> powered, high velocity blower...

If it's a 1000 HP motor and 95% efficient, then it's producing 50 HP of
waste heat. That does indeed take a *huge* amount of cooling air -- but
that doesn't mean low efficiency.

> One afternoon I was pulling a full load of steel to the plant when
> one of the ducts came loose. The result was that the truck motors
> overheated in minutes sufficient to catch on fire. No harm done,
> apparently just oil burning off, for after I put the fire out with a
> CO2 fire extinguisher and slipped the duct back in place, I continued
> on up the hill.
>
> With that kind of heat being dissipated in the motors, the drivetrain
> could not have been very efficient.

Well, with 50 KW of heat into a 500 lbs motor, it would only take a
matter of minutes to overheat.

> I bet that modern hydraulics could compete with that system. I do
> know that many pieces of heavy equipment now have pure hydraulic
> drives. The engine spins a hydraulic pump and the fluid operates
> everything including the tracks or wheels.

Could be. A hydraulics professor told me that hydraulics aren't quite as
good as electrics, but they use them because of the dirty locations
where such equipment gets used. The electric systems are typically air
cooled, and so need lots of clean dry air. The hydraulics are naturally
oil cooled, which is easier in bad environments. Air cooling is also bad
in explosive environments like a mine.

> It's interesting that even before this last fuel price run-up, there
> began a big move to shift heavy equipment over to electric grid power
> whenever possible. Bobcat makes an electric skid-steer. My friend at
> the scrap metal yard just ordered one. Yep, it trails an umbilical
> behind it. Not battery powered.

The big taconite mines in northern Minnesota have used equipment with
electric cords for at least 50 years. On a tour, they showed us a one of
their gigantic shovels with a scoop as big as a 2-car garage. It was
powered by a cord as big as your arm. This one had been retired after 40
years of service, as it was no longer big enough!

--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
Robert MacDowell
2008-07-13 18:29:28 UTC
Permalink
Lee Hart wrote:
> Neon John wrote:
>> I'd be afraid to even guess at the efficiency but the 1000 hp switch
>> engine that I ran for TVA for a couple of years definitely was NOT
>> highly efficient... Each truck set was cooled by a very high
>> powered, high velocity blower...
>
> If it's a 1000 HP motor and 95% efficient, then it's producing 50 HP of
> waste heat. That does indeed take a *huge* amount of cooling air -- but
> that doesn't mean low efficiency.

Locomotives have 4-6 motors, so divide horsepower and heat by 4-6.
Neon John's probaby had 250hp going into each motor, dissipating 12.5hp.
Modern 6000hp locomotives have 6 motors, 1000hp per motor, and very
aggressive (loud) traction motor blowers. In the early days, motor
blowers were gear/belt driven off the engine, so blower RPM matched
engine RPM. Now I believe they're electric blowers that can run full
speed when needed.

Streetcars, interurbans and older electric locomotives (of the style
interurban operations used) are not cooled at all. They ranged from 25
hp motors in streetcars clear up to 200+hp motors in electric
locomotives which would pull 10-25 car trains (old 40 ton cars) over
steep grades. For instance the Western Railway Museum's CCT 7, 560hp on
4 motors... or SN 654, 850hp on 4 motors which is more powerful than
early diesels. No blowers.

How do they do that? Is it helping that they are DC series wound motors?
Bob Rice
2008-07-13 16:28:00 UTC
Permalink
----- Original Message -----
From: "Neon John" <jgd-7o1kDznDRwqaMJb+***@public.gmane.org>
To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
Sent: Saturday, July 12, 2008 4:29 AM
Subject: Re: [EVDL] Diesel APUs


> On Fri, 11 Jul 2008 10:59:20 -0500, Lee Hart <leeahart-***@public.gmane.org>
> wrote:
>
>
>>The system in a diesel-electric locomotive is 100 times larger. A 1000
>>HP electric motor or generator is more like 95% efficient. Their
>>controllers are likewise slightly more efficient, and there are no
>>batteries to buffer the power, so no losses there (they use all the
>>power they generate immediately, without having to store it and recover
>>it later). Thus they can get an 85-90% overall efficiency -- that's
>>better than they could get with hydraulics or conventional transmissions.
>
> I'd be afraid to even guess at the efficiency but the 1000 hp switch
> engine
> that I ran for TVA for a couple of years definitely was NOT highly
> efficient.
> It had two truck sets with two 600 volt DC motors on each truck. Each
> motor
> drove the axle through what looked like about a 3:1 gear reduction. Each
> truck set was cooled by a very high powered, high velocity blower that
> supplied air from the engine compartment to the trucks through a flex
> duct.
> Each blower was something like 5 HP. Another large blower cooled the
> brush-type DC generator direct-coupled to the engine. 1000 HP at 750
> RPM -
> torque monster :-)
> Hi John;
Sounds like fun? Was it a EMD or Generous Electric?Musta been an oldie? No
matter they HAVE to have traction motor blowers!For example the Metro
North's M-1 and M-2 Commuter jobs are a 4 motor car. Motors are rated at 55
HP on cooled, 185 HP with the turbo blower working. Antrak's AEM-7 electric
lokies, 4 axle, 4 motor machines just shut the TM down if the blower
fails!Game over! The OTHER 3 motors are stuck with getting you over the
road!I think space ois an issue with RR Tm's as they HAVE to fit inside the
confines of the truck, RR speak for wheel assembly, under each end of a
lokie.They HAVe to be able to accept hidiously high starting and pulling
amps. WHY the comm area of a RR motor is hugh and multiple brushes are the
norm. Then ya run on one of the steepest RR grades out there. All kinds of
things, I can see why you would question Electric drive. Be like having John
Wayland tow my 6 ton Bus Camper with the Zombie!Oh it would DO it, awile,
before cooking the Siamese motors, not to mention rear tires?But this would
be an on-road similarity thing here?John would hafta have a RR like blower
system on Zombie anf Jim Husted would tell him to cut it out! No, I should
say, tow a Big Rig, with 80k lbs, now THAT would be fairer to the RR
lokie?And up that grade out of LA, Grapevine I think they call it?So IF ya
put things in perspective toward the RR traction motor thing? Freight trains
routinely drive off with deadweight of a small cruise ship in tow!In that
the motors will stand for it, is pretty amazing.So I would say that you are
nowhere near the 90 % efficiency WE pay for with TM's, but ya figure as Lee
sez, that even a 10-20% loss is a HELLOVA lot of heat! Gotta go somewhere?

Hydralic drive trains are more common in Europe and Japan, as train
weights are about half, and you can cool hot hydralic fluid easier than TM
heat with hurricanes of air? Hydralic lokies were tried here about 40 years
ago, with Krass-Maffi diesel Hydralics, not correct spelling here, but ,
like I always do, close. They tried them on the SP and Reo Grande RR's they
worked OK, but were orphens from, the get go, in an EMD world. The Budd RDC
Car was a roaring success, with a torque converter setup, we would still
have them on Amtrak, IF anybody still wanted them, shopwarn and shabby
toward the end. No new car smell anymore, just mouldy, diseasel one!But as I
remember worked well. But it was a feather weight 55 tons!

> According to folks who knew a LOT more about it than I did, the grade
> coming
> off the Southern line in Soddy-Daisy and leading to the Sequoyah Nuclear
> Plant
> was the third steepest railroad grade in the country. In any event, a
> full
> load up that grade was 4 or 5 open top cars loaded with pre-fabricated
> steel
> structures.

I guees ya came down empty?Holding back loads can be scary, too!On THAT
grade(cliff?)No Dynamic brake on that lokie?

> One afternoon I was pulling a full load of steel to the plant when one of
> the
> ducts came loose. The result was that the truck motors overheated in
> minutes
> sufficient to catch on fire. No harm done, apparently just oil burning
> off,
> for after I put the fire out with a CO2 fire extinguisher and slipped the
> duct
> back in place, I continued on up the hill.

In that you didn't kill the TM's involved, you were lucky, or enjoyed the
robust TM construction!

> With that kind of heat being dissipated in the motors, the drivetrain
> could
> not have been very efficient.

Good point, but WHATEVER drive train, you would getalot of heat. IF the
engine was a :Stick Shift, BIG clutch and tranny, cardon shafts to the axles
like a Shay type setup, geared, direct drive, it woulda been an interesting
setup? Trux do it all the time. Road Ranger 10 speeds?

> I bet that modern hydraulics could compete with that system. I do know
> that
> many pieces of heavy equipment now have pure hydraulic drives. The engine
> spins a hydraulic pump and the fluid operates everything including the
> tracks
> or wheels.
Good point. I don't know of any US-ian Lokie builders doing this. We
are pretty hide-bound tradition wize in turming lokie wheels.Once the train
gets rolling they just float along at a fraction of starting anf heavy
pulling amps. Sorta like driving an Electric car?Think of cruising along
with 8 Amfleet cars in tow, 75 mph, at about the amps I use in my Jetta. Of
couse, it's at a tad more volts!!

> It's interesting that even before this last fuel price run-up, there began
> a
> big move to shift heavy equipment over to electric grid power whenever
> possible. Bobcat makes an electric skid-steer. My friend at the scrap
> metal
> yard just ordered one. Yep, it trails an umbilical behind it. Not
> battery
> powered.
>
> He's about to order a large electric track-hoe to replace the
> diesel-powered
> one that he has now. They use over 1000 gallons of diesel a week so even
> with
> demand charges, the payback will be rapid.

Hmmm? Demand charges? How does that work? IF he grabs a BIG bite of stuff
he hasta PAY like for 15 minutes at that rate EVen if the guy's on coffee
break?

Seeya

Bob, ANOTHE train driver
Neon John
2008-07-14 01:16:02 UTC
Permalink
On Sun, 13 Jul 2008 12:28:00 -0400, "Bob Rice" <bobrice-***@public.gmane.org> wrote:


>> Hi John;
> Sounds like fun? Was it a EMD or Generous Electric?

General Electric. It had a placard on the side signifying that it had served
in Normandy during the Big One. Yep, it was an oldie but a goodie.

>Musta been an oldie? No
>matter they HAVE to have traction motor blowers!For example the Metro
>North's M-1 and M-2 Commuter jobs are a 4 motor car. Motors are rated at 55
>HP on cooled, 185 HP with the turbo blower working. Antrak's AEM-7 electric
>lokies, 4 axle, 4 motor machines just shut the TM down if the blower
>fails!Game over! The OTHER 3 motors are stuck with getting you over the
>road!I think space ois an issue with RR Tm's as they HAVE to fit inside the
>confines of the truck, RR speak for wheel assembly, under each end of a
>lokie.They HAVe to be able to accept hidiously high starting and pulling
>amps.

Yep. The cables running to the trucks were as large as my wrists. The
mechanics told me that they'd opened up the injector pumps to give the engine
more power to aid in climbing that slope. I know that I had to really feather
the throttle to keep from spinning and wearing divots in the rails. The sand
system didn't work.

I'm curious about something, Bob. The mechanics told me that the motors had
ceramic insulation around the windings, which is why catching fire didn't hurt
them. True?

> Hydralic drive trains are more common in Europe and Japan, as train
>weights are about half, and you can cool hot hydralic fluid easier than TM
>heat with hurricanes of air? Hydralic lokies were tried here about 40 years
>ago, with Krass-Maffi diesel Hydralics, not correct spelling here, but ,
>like I always do, close. They tried them on the SP and Reo Grande RR's they
>worked OK, but were orphens from, the get go, in an EMD world. The Budd RDC
>Car was a roaring success, with a torque converter setup, we would still
>have them on Amtrak, IF anybody still wanted them, shopwarn and shabby
>toward the end. No new car smell anymore, just mouldy, diseasel one!But as I
>remember worked well. But it was a feather weight 55 tons!
>
>> According to folks who knew a LOT more about it than I did, the grade
>> coming
>> off the Southern line in Soddy-Daisy and leading to the Sequoyah Nuclear
>> Plant
>> was the third steepest railroad grade in the country. In any event, a
>> full
>> load up that grade was 4 or 5 open top cars loaded with pre-fabricated
>> steel
>> structures.
>
> I guees ya came down empty?Holding back loads can be scary, too!On THAT
>grade(cliff?)No Dynamic brake on that lokie?

Empty return trips. We hauled mostly prefab steel for Sequoyah but also
components for the Raccoon Mountain Pumped storage facility. Those parts were
hauled down to a dock and put on a barge for the trip to RM.

Parts included the turbine wheels for the pump/generators. Huge affairs that
came in on specially made low-boy cars so the thing could clear the tunnels. I
bet that the bottom of the wheel wasn't more than 3" off the ties.

I managed to derail one of those :-) Not my fault, as it turns out. TVA
built the switch yard on a grade. The car didn't have a brake shoe on it.
After chocking the wheels and winding down the brakes, I pulled the coupling -
and the thing took off like it was jet-propelled, eating the chocks like they
weren't there. It hit a pile of dirt at the end of the rail, jumped up in the
air a few feet and flopped over. White (management) and green (engineers)
hats swarmed the place like ants at a picnic.

Those wheels were so heavy that I could only make a single car run with those.

> Good point. I don't know of any US-ian Lokie builders doing this. We
>are pretty hide-bound tradition wize in turming lokie wheels.Once the train
>gets rolling they just float along at a fraction of starting anf heavy
>pulling amps. Sorta like driving an Electric car?Think of cruising along
>with 8 Amfleet cars in tow, 75 mph, at about the amps I use in my Jetta. Of
>couse, it's at a tad more volts!!

I figure that if EVs ever become a significant part of the national fleet,
it'll be with the assistance of overhead wires, railroad style. Semi trucks
would be the first logical candidates, given how much fuel they burn and how
high they are anyway. Wired highways and diesel to get to the docks.

>> He's about to order a large electric track-hoe to replace the
>> diesel-powered
>> one that he has now. They use over 1000 gallons of diesel a week so even
>> with
>> demand charges, the payback will be rapid.
>
> Hmmm? Demand charges? How does that work? IF he grabs a BIG bite of stuff
>he hasta PAY like for 15 minutes at that rate EVen if the guy's on coffee
>break?

There are two components to commercial and industrial power bills. The energy
charge for the kWh used and a demand charge based on the highest kW demand
during billing interval. Demand is computed as the average on either a 15 or
30 minute basis. 30 minutes in this area.

Demand charges REALLY hurt! I don't have the latest local rate card but the
last increase was only 2% so the old one is representative. Here's the
relevant part:

COMMERCIAL SKED GSA

UP TO 15,000 KWH PER MONTH,
LESS THAN 50 KW DEMAND

8.20 BASE RATE <---- fixed monthly "meter fee"
6.022 CENTS PER KWH

>15,000 KWH,
50-1000 KW DEMAND

8.20 BASE
6.022 PER KWH, FIRST 15,000
2.992 PER KWH AFTER 15,000 KWH
8.88 PER KW OVER 50 KW

That $8.88 cents per kW is a killer. If the demand hits 100kW only ONCE
during the month, then he pays 50*$8.88 = $444.00 JUST for the demand charge.
This is in addition to the energy charge.

Of course, the major customers such as factories, mills and stuff negotiate
special deals. TVA is very good about that in order to attract manufacturing.
The guys that really take it in the nose are the ones on the first tier.

For anything over 200 amp service they install demand meters. That's why I
had 3 200 amp service entrances on my building to supply my restaurant and
neon shop. I might only run the kitchen balls-out once or twice a month for a
very large catering job and I damn sure didn't want to get hit for the demand
charges. So I had the restaurant loads split up into 3 sections, with one
section also feeding the neon shop.

Demand charges were also the reason that every heating appliance in my place
that could run on natural gas did run on natural gas. The local electric
utility regularly offered me incentives to change, offering to pay for the
appliances, in some cases. That pesky little demand charge thing always
stopped the deal in its tracks.

The neon shop was also highly peaky, demand-wise. My bombarder that processed
the finished tubes could draw almost 200 amps. A bombarding cycle only lasted
about 3 minutes but if I was in high production mode, I could do a batch every
10-15 minutes. That could have resulted in a relatively huge demand hit when
the shop AC, lights, air compressor and all the other equipment was added in.
The bombarder fed off one meter and the balance of the shop off another. None
of the meters had demand registers so splitting the load was to balance the
draw from each meter and not overload it.

Demand charges are going to make rapid EV charging, particularly at public
locations, interesting. A savvy C-store operator, for example, is going to
have to figure demand charges in his decision as to whether he installs
charging stations and how much to charge for their use. A 50 amp, 240 volt
charger represents 12kW or $106 in demand charges over and above the energy
dispensed.

It'll be even more interesting if he has several stations available. A
once-a-month pile up where every station was being used at once would cost a
small fortune.

That demand gets charged even if it only happens once a month so a proprietor
would have to have some assurance of a lot of business to make it worthwhile.
Or figure out how to set up a separate business and have a separate meter for
the charging stations. That might be complicated, as most utilities won't
allow multiple meters to avoid demand charges. I had to set up three
different businesses, complete with business licenses, to get mine.

John
--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
Beware the lollipop of mediocrity. Lick once and you suck forever.
Robert MacDowell
2008-07-11 19:35:20 UTC
Permalink
Peter VanDerWal wrote:
>>> As electric motors get larger they tend to get more efficient.
>>>
>>> We aren't talking about the huge motors in trains, but the relatively
>>> tiny
>>> EV motors used in automobiles.
>> A clock motor is "relatively tiny". An EV motor is big enough that the
>> physics are going to be about the same as on the railroad.
>
> When item A is 1% of the size/weight of item B, then I consider item A
> relatively tiny compared to item B.
>
> A 9" ADC (a "large" ec motor) is rated at 20 hp continuous.
> Diesel-electric locomotives are rate at around 3,000 hp continous. That
> makes the EV motor LESS THAN 1% of the size of a diesel motor.
>
> If you would bother to look up the facts,

You know, Peter, that's really insulting and not called for.

> you'd see that a 9" ADC is rated
> at approx 88% PEAK efficiency. There was a NASA ressearch document
> recently posted to the list that clearly showed that a motors efficiency
> DROPS when PWM (the normal speed control method used in EVs), further the
> controller itself drops 2-3% of the power.
> When yo do the math, and take into consideration that the motor doesn't
> operate at it's peak efficiency point most of the time, 80% is pretty
> close.

Ah, you're confusing "peak efficiency" with "efficiency at peak" (peak
something else).

> If you would bother to

Again I think you're really being inappropriate and insulting and I
think you owe me an apology.

> look up the specs of typical generator heads like
> the one described in the original post, 80% is generous, especially when
> you add in the AC to DC conversion.
>
>> I'm sure that you believe what you say, but you're misinterpreting the
>> data somehow.
>
> I believe it because, unlike you I looked it up.

But you must admit, that does not exclude the possibility that you
misinterpreted what you looked up.

>> For instance, an EV drag-racer probably does lose 20% of its energy in
>> the windings of the motor... for 12.318 seconds :) but darn well not
>> continuously.
>
> See, now you're just making things up. Why don't you look up the facts?
> try this torque chart:
> http://www.evparts.com/img/mt2120torquecurvebyus.PDF
>
> It shows that a 9" ADC running at 1200 amps (kind of pokey for a drag
> racer these days) is running at approx 55% efficiency.
>
> If you want to post some REAL information that disproves my statement, go
> ahead, but don't try to prove your argument by making up numbers.

Peter, I think you're really being beyond inappropriate here, and I'm
not going to continue this discussion with you.


>
>
>> A common automotive alternator loses 20% because it has two 1-volt drops
>> from the diodes. On 12V, 2V is a lot.
>
> Common automotive alternators loose a LOT more than 20%
>> For instance this data would be easy to misinterpret:
>> http://www.go-ev.com/images/003_12_WarP_8_SpreadSheet.jpg
>
> And how exactly would you misinterpret that? They list the efficiency
> right their, no interpretation necessary. It clearly shows efficiency
> varies from ~82% to 84% at the power levels they are charting, and that's
> without PWM or taking controller losses into account.
>
> The data you're posting proves MY point not yours.
>
Peter VanDerWal
2008-07-11 14:27:52 UTC
Permalink
>> If you would bother to look up the facts,
>
> You know, Peter, that's really insulting and not called for.

I didn't think it was insulting, but I admit I was getting annoyed that
you are disputing published facts because they don't agree with your
personal beliefs.

Especially when you try to tell me what I'm thinking or believing.

>> When yo do the math, and take into consideration that the motor doesn't
>> operate at it's peak efficiency point most of the time, 80% is pretty
>> close.
>
> Ah, you're confusing "peak efficiency" with "efficiency at peak" (peak
> something else).

No I'm not. "Peak Efficiency" is a single point on the torque curve. At
any given voltage it occurs at a single RPM/Torque point.
There are numerous "near" peak efficiency points that occur near this
point, but technically they are not the "peak" efficiency point.
Every readily available motor that I have seen torque charts on also
suffers from lower efficiency when operated below it's rate voltage.
If you have a 120V motor in a 120V EV, then it is ALWAYS operating below
it's rated voltage unless you bypass the controller.
If you are running at 10% duty cycle, then the motor is seeing ~12V and if
you look at a 12V torque chart for a 120V ADC motor, the "peak" efficiency
point is below 80%, way below it.
Further more, the NASA paper recently posted shows that a motor operating
at a PWM average voltage of 12V is less efficient than the same motor
runing on 12V straight DC.
Finally ask any EV controller manufacturer what their controller
efficiency is, I'm not aware of any the exceed 98%.

>
>> If you would bother to
>
> Again I think you're really being inappropriate and insulting and I
> think you owe me an apology.

Fair enough, if you apologize for calling me a liar, then I will apologize
for saying that you haven't bothered looking up the facts.

>> look up the specs of typical generator heads like
>> the one described in the original post, 80% is generous, especially when
>> you add in the AC to DC conversion.
>>
>>> I'm sure that you believe what you say, but you're misinterpreting the
>>> data somehow.
>>
>> I believe it because, unlike you I looked it up.
>
> But you must admit, that does not exclude the possibility that you
> misinterpreted what you looked up.

If you can show me how I misinterpreted the facts, then I will admit that
I did. It's been a while since I took any math classes. so maybe I'm
getting rusty, but as far as I can recall, 79% efficient is less efficient
than 80% efficient, the same goes for 78%, 77%, etc.
I don't see how this is open to "interpretation" but I'm certainly willing
to learn.

>
>>> For instance, an EV drag-racer probably does lose 20% of its energy in
>>> the windings of the motor... for 12.318 seconds :) but darn well not
>>> continuously.
>>
>> See, now you're just making things up. Why don't you look up the facts?
>> try this torque chart:
>> http://www.evparts.com/img/mt2120torquecurvebyus.PDF
>>
>> It shows that a 9" ADC running at 1200 amps (kind of pokey for a drag
>> racer these days) is running at approx 55% efficiency.
>>
>> If you want to post some REAL information that disproves my statement,
>> go
>> ahead, but don't try to prove your argument by making up numbers.
>
> Peter, I think you're really being beyond inappropriate here, and I'm
> not going to continue this discussion with you.

Ok, I'm stumped. Do you mean that you didn't make this 20% figure up? If
so how did you measure it? If you didn't measure it, can you post where
you saw it published?

I will happily, and publicly, apologize for saying you made it up, if you
can show that you didn't.

P.s. If you can't show how I "misinterpreted" the facts, I'd like a public
apology for your claims that I did.
Jeff Shanab
2008-07-12 14:10:41 UTC
Permalink
I have been planning to use a pc as a digital dash for years. The
problem is finding a PC and a display that can work at 160 degrees F.
Especially while under power like when you first turn the key after the
car sits in a Fresno ca parking lot for 2 hours. For this reason I
looked at the gumstik with the samsung touch screen and some amd geode
powered industrial PCs. I have thought about hacking the kindle. The
display is "digital paper" Very low power black and white, but again
the pc is connected to the display so you can't get it out of the sun.
I'd try and split it, put the pc in an aluminum case and put a fan on it.

At least the PDA/iTouch route allows you to just take it with you.
Peter VanDerWal
2008-07-12 08:20:33 UTC
Permalink
> I have been planning to use a pc as a digital dash for years. The
> problem is finding a PC and a display that can work at 160 degrees F.
> Especially while under power like when you first turn the key after the
> car sits in a Fresno ca parking lot for 2 hours. For this reason I
> looked at the gumstik with the samsung touch screen and some amd geode
> powered industrial PCs. I have thought about hacking the kindle. The
> display is "digital paper" Very low power black and white, but again
> the pc is connected to the display so you can't get it out of the sun.
> I'd try and split it, put the pc in an aluminum case and put a fan on it.
>

Speaking of which...I just bought several of these to use as servers:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWNX:IT&item=230265100393

Geode processor, 2 serial, 1 parallel port, and 2 USB, as well as sound
and graphics. And it's fanless.
Run it with Flash drives and you'd have no moving parts.
These would probably be good in an automotive application and they only
draw ~10 watts (~5w for board + ~5w for CF/HDD) so you could leave them on
continuously if needed.

Another option are the ALIX boards:
http://www.mini-box.com/Alix-3C-Board-3-LAN-1-MINI-PCI-1_2?sc=8&category=19
http://www.mini-box.com/Alix-1C-Board-1-LAN-1-MINI-PCI?sc=8&category=19
Not quite as much builtin I/O, but, unlike the Nagasaki above, these can
run directly off the accessory battery and they're new.
Both can handle several optional mini-pci wireless cards, including a
900mhz "non-line-of-sight" card, and if you go with the Alix-3c, they even
have a waterproof outdoor case available.
Jeff Shanab
2008-07-12 20:16:29 UTC
Permalink
Yup, I see those around work a lot.
My daily work is on a box that has it's main OS and all software on a
2GB flash.
The terabyte drive is for video and database storage. (amazing what you
can do with a celeron when all encodeing has it's own chip, records 20
4SIF channels )

The point I want to make is that i have worked there 2 years and we burn
the flash over and over again.
They come with a little extra capacity and loose capacity as the extra
bytes get marked bad. We have had to replace all of them.
So...It is important to disable swap and not run a journaled file system.

Linux no swap partition and ext2 works well. Another item I work with is
a little IP security camera. This item is surprising. the board is just
a few square inches but it has montavista linux on it, runs a web server
and our video encoder/server and you can still ssh in and execute all
the command line stuff you like. This item is PPC based and only has 2
chips. Fanless and able to work in hostile environments. There are
boards out there like this that cost less than donating my smart phone)

BitzyXB http://www.appliedlinux.net/Linux_SBC.htm
gumstix http://www.gumstix.com getting popular, very active development
(the other list I am on) Has add on for I/O.
EMAC http://www.emacinc.com/linux2_sbc.htm Hate the name, I'm more a
vi guy.

Hide a computer on a board he he
http://www.linuxdevices.com/news/NS8386088053.html
Bill Dennis
2008-07-13 13:51:31 UTC
Permalink
While the batteries were charging last night, something happened that I
thought wasn't supposed to occur. When the PFC-30 was charging, I
touched a cell terminal and the chassis at the same time. And I got
zapped. I did some testing with the voltmeter, and found that when the
PFC-30 is off, there is no voltage between the traction pack and the
chassis. But when the PFC-30 is on, one end of the traction pack has
+60V to the chassis, and the other end of the traction pack has -60V to
the chassis. This was while charging from the 240V AC mains. The
PFC-30's green grounding wire, as well as its case, are connected to the
chassis, per the instructions in Manzanita's manual. I think Don
Cameron had this same problem a few years ago, but I don't know if he
ever got it resolved. Any suggestions?

Bill Dennis
Evan Tuer
2008-07-13 14:03:02 UTC
Permalink
On Sun, Jul 13, 2008 at 2:51 PM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
> While the batteries were charging last night, something happened that I
> thought wasn't supposed to occur. When the PFC-30 was charging, I
> touched a cell terminal and the chassis at the same time. And I got
> zapped.

Of course you will! The PFC chargers are not isolated. So the pack
is electrically connected to the live wire of the supply. The live
wire has a potential to ground, so you will get some fraction of that
depending on where you made contact.

This is why you should always use the following precautions:
1) always use a GFCI circuit breaker.
2) Insulate everything that is live when the charger is on.
3) if you're working on it with covers removed, insulate *yourself* -
wear rubber gloves and boots as necessary, use insulated tools, and be
careful.

As an option, convert the supply to be isolated, using an isolation
transformer (these are big and heavy, so you can't really take it with
you). Or change to using an isolated charger if you can't avoid the
risk sufficient with the above ideas.
Bill Dennis
2008-07-13 14:17:08 UTC
Permalink
Evan,
My understanding was that, yes, the battery pack is no isolated from
the mains. But the charger itself is not connected to chassis unless
there is some fault. Inside the PFC-30, the green and white wires are
not connected to each other, and only the green wire is connected to the
charger's casing. Therefore, under normal circumstances, there should
be no path from the chassis to the traction pack. Is my understanding
incorrect?

Bill Dennis

Evan Tuer wrote:
> On Sun, Jul 13, 2008 at 2:51 PM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
>
>> While the batteries were charging last night, something happened that I
>> thought wasn't supposed to occur. When the PFC-30 was charging, I
>> touched a cell terminal and the chassis at the same time. And I got
>> zapped.
>>
>
> Of course you will! The PFC chargers are not isolated. So the pack
> is electrically connected to the live wire of the supply. The live
> wire has a potential to ground, so you will get some fraction of that
> depending on where you made contact.
>
> This is why you should always use the following precautions:
> 1) always use a GFCI circuit breaker.
> 2) Insulate everything that is live when the charger is on.
> 3) if you're working on it with covers removed, insulate *yourself* -
> wear rubber gloves and boots as necessary, use insulated tools, and be
> careful.
>
> As an option, convert the supply to be isolated, using an isolation
> transformer (these are big and heavy, so you can't really take it with
> you). Or change to using an isolated charger if you can't avoid the
> risk sufficient with the above ideas.
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
>
>
Evan Tuer
2008-07-13 14:32:46 UTC
Permalink
On Sun, Jul 13, 2008 at 3:17 PM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
> Evan,
> My understanding was that, yes, the battery pack is no isolated from
> the mains. But the charger itself is not connected to chassis unless
> there is some fault.

Whether the chassis is connected to ground or not is immaterial - if
you're going to touch live connections, you're going to get a shock,
end of story.

> Inside the PFC-30, the green and white wires are
> not connected to each other, and only the green wire is connected to the
> charger's casing.

But you've grounded the car chassis as well, right? So the car
chassis is connected to ground whenever it's plugged in. The pack has
a potential to ground, and thus the chassis.

Even if you intentionally left it the bodywork disconnected (which is
a bad idea), there's no guarantee it will remain floating.

And again, even if the chassis was floating, this is no sensible way
of preventing a shock.

> Therefore, under normal circumstances, there should
> be no path from the chassis to the traction pack. Is my understanding
> incorrect?

Yes! See above.

I don't know why you're still confused about this, you asked back in 2006:

"So if, while charging, I touch any battery terminal and the car chassis,
some of the current will go back through me then the chassis and then to the
GFI breaker, which will detect unbalanced currents on its load/line earth
ground lines, and trip. "

Are you actually using a GFCI now?
Bill Dennis
2008-07-13 15:28:05 UTC
Permalink
Yes, the breaker is a GFI breaker. And I'm still confused because
sometimes there's a gap of understanding, or you're thinking about
something in a particular wrong way that occludes full understanding.
That's my current situation, and apparently has been since at least 2006.

Bill Dennis

Evan Tuer wrote:
> On Sun, Jul 13, 2008 at 3:17 PM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
>
>> Evan,
>> My understanding was that, yes, the battery pack is no isolated from
>> the mains. But the charger itself is not connected to chassis unless
>> there is some fault.
>>
>
> Whether the chassis is connected to ground or not is immaterial - if
> you're going to touch live connections, you're going to get a shock,
> end of story.
>
>
>> Inside the PFC-30, the green and white wires are
>> not connected to each other, and only the green wire is connected to the
>> charger's casing.
>>
>
> But you've grounded the car chassis as well, right? So the car
> chassis is connected to ground whenever it's plugged in. The pack has
> a potential to ground, and thus the chassis.
>
> Even if you intentionally left it the bodywork disconnected (which is
> a bad idea), there's no guarantee it will remain floating.
>
> And again, even if the chassis was floating, this is no sensible way
> of preventing a shock.
>
>
>> Therefore, under normal circumstances, there should
>> be no path from the chassis to the traction pack. Is my understanding
>> incorrect?
>>
>
> Yes! See above.
>
> I don't know why you're still confused about this, you asked back in 2006:
>
> "So if, while charging, I touch any battery terminal and the car chassis,
> some of the current will go back through me then the chassis and then to the
> GFI breaker, which will detect unbalanced currents on its load/line earth
> ground lines, and trip. "
>
> Are you actually using a GFCI now?
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
>
>
Neon John
2008-07-14 02:18:29 UTC
Permalink
On Sun, 13 Jul 2008 08:17:08 -0600, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:

>Evan,
> My understanding was that, yes, the battery pack is no isolated from
>the mains. But the charger itself is not connected to chassis unless
>there is some fault. Inside the PFC-30, the green and white wires are
>not connected to each other, and only the green wire is connected to the
>charger's casing. Therefore, under normal circumstances, there should
>be no path from the chassis to the traction pack. Is my understanding
>incorrect?

No, your understanding is correct. However, there are many paths to ground,
not the least of which are the conductive tires on your car. They're made
conductive to minimize static buildup. The most likely path was from the
battery terminal, through you to the car chassis, through the tires and to
ground (assuming a concrete floor). From there, through the soil, the ground
rod at your service entrance and back to the neutral.

That's just one guess. That a path exists is proven :-) Figuring it out
simply involves some detective work.

If you're going to be routinely working on the car while it's on charge then I
highly recommend buying an isolation transformer to protect yourself from
electrocution.

John
--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
Multitasking: Reading in the bathroom!
Bill Dennis
2008-07-14 03:42:22 UTC
Permalink
Neon John wrote:

>If you're going to be routinely working on the car while it's on charge then I
>highly recommend buying an isolation transformer to protect yourself from
>electrocution.

Thanks, John. If I'm routinely going to be working on the car while charging, I think I'd better buy myself a burial plot. My lesson has been learned.

Bill Dennis
joe
2008-07-13 14:21:02 UTC
Permalink
Just don't ever touch the connections with the charger on!!

Joseph H. Strubhar

Web: www.gremcoinc.com

E-mail: joe-XfpEAlGaYgl8UrSeD/***@public.gmane.org
----- Original Message -----
From: "Evan Tuer" <evan.tuer-***@public.gmane.org>
To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
Sent: Sunday, July 13, 2008 7:03 AM
Subject: Re: [EVDL] PFC-30 Tingle


> On Sun, Jul 13, 2008 at 2:51 PM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
>> While the batteries were charging last night, something happened that I
>> thought wasn't supposed to occur. When the PFC-30 was charging, I
>> touched a cell terminal and the chassis at the same time. And I got
>> zapped.
>
> Of course you will! The PFC chargers are not isolated. So the pack
> is electrically connected to the live wire of the supply. The live
> wire has a potential to ground, so you will get some fraction of that
> depending on where you made contact.
>
> This is why you should always use the following precautions:
> 1) always use a GFCI circuit breaker.
> 2) Insulate everything that is live when the charger is on.
> 3) if you're working on it with covers removed, insulate *yourself* -
> wear rubber gloves and boots as necessary, use insulated tools, and be
> careful.
>
> As an option, convert the supply to be isolated, using an isolation
> transformer (these are big and heavy, so you can't really take it with
> you). Or change to using an isolated charger if you can't avoid the
> risk sufficient with the above ideas.
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
> No virus found in this incoming message.
> Checked by AVG - http://www.avg.com
> Version: 8.0.138 / Virus Database: 270.4.10/1549 - Release Date: 7/12/2008
> 4:31 PM
>
>
>
Bill Dennis
2008-07-13 14:28:59 UTC
Permalink
Joe, I didn't do it on purpose! So I definitely need to be more
careful. But I still didn't think there should be a path from the
traction pack to the chassis.

Bill Dennis

joe wrote:
> Just don't ever touch the connections with the charger on!!
>
> Joseph H. Strubhar
>
> Web: www.gremcoinc.com
>
> E-mail: joe-XfpEAlGaYgl8UrSeD/***@public.gmane.org
> ----- Original Message -----
> From: "Evan Tuer" <evan.tuer-***@public.gmane.org>
> To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
> Sent: Sunday, July 13, 2008 7:03 AM
> Subject: Re: [EVDL] PFC-30 Tingle
>
>
>
>> On Sun, Jul 13, 2008 at 2:51 PM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
>>
>>> While the batteries were charging last night, something happened that I
>>> thought wasn't supposed to occur. When the PFC-30 was charging, I
>>> touched a cell terminal and the chassis at the same time. And I got
>>> zapped.
>>>
>> Of course you will! The PFC chargers are not isolated. So the pack
>> is electrically connected to the live wire of the supply. The live
>> wire has a potential to ground, so you will get some fraction of that
>> depending on where you made contact.
>>
>> This is why you should always use the following precautions:
>> 1) always use a GFCI circuit breaker.
>> 2) Insulate everything that is live when the charger is on.
>> 3) if you're working on it with covers removed, insulate *yourself* -
>> wear rubber gloves and boots as necessary, use insulated tools, and be
>> careful.
>>
>> As an option, convert the supply to be isolated, using an isolation
>> transformer (these are big and heavy, so you can't really take it with
>> you). Or change to using an isolated charger if you can't avoid the
>> risk sufficient with the above ideas.
>>
>>
>> _______________________________________________
>> For general EVDL support, see http://evdl.org/help/
>> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>>
>>
>> No virus found in this incoming message.
>> Checked by AVG - http://www.avg.com
>> Version: 8.0.138 / Virus Database: 270.4.10/1549 - Release Date: 7/12/2008
>> 4:31 PM
>>
>>
>>
>>
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
>
>
Ben
2008-07-13 14:33:42 UTC
Permalink
Bill,

There isn't a path, until you make contact. The PFC makes a path from ground
to the frame, and the pack is tied to the live connection - so there is
potential between them.

Ben

On Sun, Jul 13, 2008 at 10:28 AM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:

> Joe, I didn't do it on purpose! So I definitely need to be more
> careful. But I still didn't think there should be a path from the
> traction pack to the chassis.
>
> Bill Dennis
>
>
Bill Dennis
2008-07-13 15:26:09 UTC
Permalink
I'm still not getting it. There must be a gap in my understanding.

1) When I touch the pack and the chassis, there is a path from the pack
to the chassis through me.
2) There is a path from the chassis to the PFC-30's case
3) Under normal circumstances, there is no connection inside the PFC-30
between the case and any other wire.
4) Green and white are connected back in the breaker box.

So is the circuit completed by going back through the breaker box, then
into the PFC-30 again through the white wire?

Bill Dennis

Ben wrote:
> Bill,
>
> There isn't a path, until you make contact. The PFC makes a path from ground
> to the frame, and the pack is tied to the live connection - so there is
> potential between them.
>
> Ben
>
> On Sun, Jul 13, 2008 at 10:28 AM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
>
>
>> Joe, I didn't do it on purpose! So I definitely need to be more
>> careful. But I still didn't think there should be a path from the
>> traction pack to the chassis.
>>
>> Bill Dennis
>>
>>
>>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
>
>
Evan Tuer
2008-07-13 15:45:49 UTC
Permalink
On Sun, Jul 13, 2008 at 4:26 PM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
> I'm still not getting it. There must be a gap in my understanding.
>
> 1) When I touch the pack and the chassis, there is a path from the pack
> to the chassis through me.

Correct.

> 2) There is a path from the chassis to the PFC-30's case

Assuming the case is bolted into the car, or both the chassis and the
charger are grounded with the green wire, yes.

> 3) Under normal circumstances, there is no connection inside the PFC-30
> between the case and any other wire.

OK. But there's a voltage difference between the case (ground) and
both the input and output of the charger; that's the important bit.

> 4) Green and white are connected back in the breaker box.

Or somewhere, yes.

> So is the circuit completed by going back through the breaker box, then
> into the PFC-30 again through the white wire?

Err.. The current goes through you, to ground, back to the generator.
That's all there is to it. No matter whether the nearest ground is
the car chassis or the pavement. Clearer?


Now, why didn't your breaker trip?
First of all, you said it was just a tingle: perhaps not enough to
trip the breaker but you still noticed it, right?
Or perhaps the breaker isn't working? Have you tested it since?
Or perhaps it didn't trip because you've not got a sinusoidal fault
current (it's rectified by the charger) so a standard AC GFCI won't
work properly. What type is it?

This is the reason I stress that it's not enough to just rely on a
GFCI for protection.
Bill Dennis
2008-07-13 16:03:23 UTC
Permalink
Evan Tuer wrote:

>Err.. The current goes through you, to ground, back to the generator.
>that's all there is to it. No matter whether the nearest ground is
>the car chassis or the pavement. Clearer?

No, still unclear. Can you give the explanation without using the word "ground"? Give me the path the the electricity follows through the circuit when I touch them.

Thanks.

Bill Dennis
Evan Tuer
2008-07-13 16:21:13 UTC
Permalink
On Sun, Jul 13, 2008 at 5:03 PM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
> Evan Tuer wrote:
>
>>Err.. The current goes through you, to ground, back to the generator.
>>that's all there is to it. No matter whether the nearest ground is
>>the car chassis or the pavement. Clearer?
>
> No, still unclear. Can you give the explanation without using the word "ground"?
> Give me the path the the electricity follows through the circuit when I touch them.

I'll try!

Scenario 1:
You are standing outside the vehicle, reach in and touch the pack
while it's on charge:
Current flows from the live wire of the supply, through the charger to
the battery terminal, through your shoes to the "terra" that you are
standing on, through the earth back to the nearest supply point (where
the neutral wire is connected to an earthing rod, buried in the
"dirt").

Scenario 2: you are touching the car body with one hand and the pack
with the other hand:
Current flows from the live of the supply, through the charger to
the battery terminal, through you to the car body, through the green
wire back to the nearest supply point (where it's connected to the
white wire and the earth rod, as above).

I'll try to do a diagram if that still doesn't help...?
Bill Dennis
2008-07-13 18:14:46 UTC
Permalink
I think I overheated the Curtis 1231C today. I took the car downtown to
run errands with my wife as a passenger, then came back up that steep
road to my house again. About 1.5 miles from the house, where the
steepest part of the hill begins, the car bucked twice, then died. I
coasted over under a shady tree and waited 5 minutes, then tried again.
The car moved this time. I kept it below 15mph the rest of the way home
and encountered no additional problems. But when I opened the hood, the
Curtis was definitely real hot. So I guess there's yet another fan I
need to add.

The cells ended up at 45 degrees Celsius again.

The good news is that I've now driven 45 miles without charging the car,
and the resting voltage on the nominal 126V Li-ion pack is still 129V.

Bill Dennis
Phil Marino
2008-07-13 19:32:54 UTC
Permalink
I believe an overheated Curtis limits itself ( and makes noise while doing it) but keeps on running.


It could be that your pack voltage dropped below the minimum for the controller, and the controller dropped out because of that. Do you have a battery voltage gauge in the dash?

After a few minutes, the pack voltage would rise again ( and might stay higher if you kept the battery current lower by driving slowly) so everything would work fine.

And, maybe the controller was hot but that wasn't the problem. Of course, adding a cooling fan would still be a good idea.


Phil

> Date: Sun, 13 Jul 2008 12:14:46 -0600
> From: wjdennis-r9/***@public.gmane.org
> To: ev-UWgVIey+***@public.gmane.org
> Subject: [EVDL] Overheated 1231C
>
> I think I overheated the Curtis 1231C today. I took the car downtown to
> run errands with my wife as a passenger, then came back up that steep
> road to my house again. About 1.5 miles from the house, where the
> steepest part of the hill begins, the car bucked twice, then died. I
> coasted over under a shady tree and waited 5 minutes, then tried again.
> The car moved this time. I kept it below 15mph the rest of the way home
> and encountered no additional problems. But when I opened the hood, the
> Curtis was definitely real hot. So I guess there's yet another fan I
> need to add.
>
> The cells ended up at 45 degrees Celsius again.
>
> The good news is that I've now driven 45 miles without charging the car,
> and the resting voltage on the nominal 126V Li-ion pack is still 129V.
>
> Bill Dennis
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>

_________________________________________________________________
Use video conversation to talk face-to-face with Windows Live Messenger.
http://www.windowslive.com/messenger/connect_your_way.html?ocid=TXT_TAGLM_WL_Refresh_messenger_video_072008
Bill Dennis
2008-07-13 19:41:20 UTC
Permalink
Yes, I have an EVision, plus an analog voltage gauge. I'm pretty
certain that the voltage didn't drop below 63V, which is the Curtis'
cutoff voltage. I tried to keep it above 90V at all times, and maybe
occasionally it dipped into the upper 80's. Could the problem be
something else, like a loose connection that was overheating? Or
possibly the motor itself cutting out? Later on, I'll re-tighten all
the battery connections to be sure.

Bill Dennis

Phil Marino wrote:
> I believe an overheated Curtis limits itself ( and makes noise while doing it) but keeps on running.
>
>
> It could be that your pack voltage dropped below the minimum for the controller, and the controller dropped out because of that. Do you have a battery voltage gauge in the dash?
>
> After a few minutes, the pack voltage would rise again ( and might stay higher if you kept the battery current lower by driving slowly) so everything would work fine.
>
> And, maybe the controller was hot but that wasn't the problem. Of course, adding a cooling fan would still be a good idea.
>
>
> Phil
>
>
>> Date: Sun, 13 Jul 2008 12:14:46 -0600
>> From: wjdennis-r9/***@public.gmane.org
>> To: ev-UWgVIey+***@public.gmane.org
>> Subject: [EVDL] Overheated 1231C
>>
>> I think I overheated the Curtis 1231C today. I took the car downtown to
>> run errands with my wife as a passenger, then came back up that steep
>> road to my house again. About 1.5 miles from the house, where the
>> steepest part of the hill begins, the car bucked twice, then died. I
>> coasted over under a shady tree and waited 5 minutes, then tried again.
>> The car moved this time. I kept it below 15mph the rest of the way home
>> and encountered no additional problems. But when I opened the hood, the
>> Curtis was definitely real hot. So I guess there's yet another fan I
>> need to add.
>>
>> The cells ended up at 45 degrees Celsius again.
>>
>> The good news is that I've now driven 45 miles without charging the car,
>> and the resting voltage on the nominal 126V Li-ion pack is still 129V.
>>
>> Bill Dennis
>>
>>
>> _______________________________________________
>> For general EVDL support, see http://evdl.org/help/
>> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>>
>>
>
> _________________________________________________________________
> Use video conversation to talk face-to-face with Windows Live Messenger.
> http://www.windowslive.com/messenger/connect_your_way.html?ocid=TXT_TAGLM_WL_Refresh_messenger_video_072008
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
>
>
Evan Tuer
2008-07-13 19:52:01 UTC
Permalink
On Sun, Jul 13, 2008 at 8:41 PM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
> Yes, I have an EVision, plus an analog voltage gauge. I'm pretty
> certain that the voltage didn't drop below 63V, which is the Curtis'
> cutoff voltage. I tried to keep it above 90V at all times, and maybe
> occasionally it dipped into the upper 80's. Could the problem be
> something else, like a loose connection that was overheating?

My Curtis had this problem. It had got a little moisture in it at
some poiny (of course) which had corroded a lot of the solder joints
on the control PCB. It used to cut out without warning whenever it
got warm, and would then restart within a minute or two. It got
worse, so that it wouldn't restart for an hour!
I cleaned up the board and then re-soldered all the connections that
looked suspect. I also made a "pressure equalising device" when I
sealed up the case again (to discourage water getting in again), and
since then it hasn't recurred.
Roger Heuckeroth
2008-07-14 14:35:56 UTC
Permalink
What safeguards does you BMS have? Is it possible the the cut out was
not my the Controller, but the BMS?

Also, are you keeping the revs up above 4000 rpm while driving up
those hills?

On Jul 13, 2008, at 3:41 PM, Bill Dennis wrote:

> Yes, I have an EVision, plus an analog voltage gauge. I'm pretty
> certain that the voltage didn't drop below 63V, which is the Curtis'
> cutoff voltage. I tried to keep it above 90V at all times, and maybe
> occasionally it dipped into the upper 80's. Could the problem be
> something else, like a loose connection that was overheating? Or
> possibly the motor itself cutting out? Later on, I'll re-tighten all
> the battery connections to be sure.
>
> Bill Dennis
>
> Phil Marino wrote:
>> I believe an overheated Curtis limits itself ( and makes noise
>> while doing it) but keeps on running.
>>
>>
>> It could be that your pack voltage dropped below the minimum for
>> the controller, and the controller dropped out because of that. Do
>> you have a battery voltage gauge in the dash?
>>
>> After a few minutes, the pack voltage would rise again ( and might
>> stay higher if you kept the battery current lower by driving
>> slowly) so everything would work fine.
>>
>> And, maybe the controller was hot but that wasn't the problem. Of
>> course, adding a cooling fan would still be a good idea.
>>
>>
>> Phil
>>
>>
>>> Date: Sun, 13 Jul 2008 12:14:46 -0600
>>> From: wjdennis-r9/***@public.gmane.org
>>> To: ev-UWgVIey+***@public.gmane.org
>>> Subject: [EVDL] Overheated 1231C
>>>
>>> I think I overheated the Curtis 1231C today. I took the car
>>> downtown to
>>> run errands with my wife as a passenger, then came back up that
>>> steep
>>> road to my house again. About 1.5 miles from the house, where the
>>> steepest part of the hill begins, the car bucked twice, then
>>> died. I
>>> coasted over under a shady tree and waited 5 minutes, then tried
>>> again.
>>> The car moved this time. I kept it below 15mph the rest of the
>>> way home
>>> and encountered no additional problems. But when I opened the
>>> hood, the
>>> Curtis was definitely real hot. So I guess there's yet another
>>> fan I
>>> need to add.
>>>
>>> The cells ended up at 45 degrees Celsius again.
>>>
>>> The good news is that I've now driven 45 miles without charging
>>> the car,
>>> and the resting voltage on the nominal 126V Li-ion pack is still
>>> 129V.
>>>
>>> Bill Dennis
>>>
>>>
>>> _______________________________________________
>>> For general EVDL support, see http://evdl.org/help/
>>> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>>>
>>>
>>
>> _________________________________________________________________
>> Use video conversation to talk face-to-face with Windows Live
>> Messenger.
>> http://www.windowslive.com/messenger/connect_your_way.html?ocid=TXT_TAGLM_WL_Refresh_messenger_video_072008
>>
>> _______________________________________________
>> For general EVDL support, see http://evdl.org/help/
>> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>>
>>
>>
>>
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/
> ev
Peter Eckhoff
2008-07-13 21:36:36 UTC
Permalink
Hello All,

The TEAA recently has had a go around on heat sinking our Curtis
controllers. The manual states: "Six mounting clamps are provided,
which can be used to attach the controller to its matching heatsink
(Curtis PMC p/n 16421001) or to some other surface. ... a thermal
compound can be used to improve heat conduction from the case to the
mounting surface."

A search on the Internet for p/n 16421001 (Google search: +Curtis
16421001) brings up **only** the quote from the Curtis manual and 2 porn
site links. Several parts houses recommend a flat sheet of 1/8"
aluminum with a tube of thermal compound. Several others on this list
have found finned heat sinks from heat sink suppliers. I've noticed the
most ardent supporters of finned heat sinks come from mainly pickup
truck drivers and drivers with heavy or poorly vented cars.

The Curtis controller is a sealed unit and is cooled by convection.
"The 1231C begins reducing power at 85 C (167F). Power output will be
reduced for as long as the overheat condition remains, and full power
will return when the unit cools."

We won't know how hot our controllers get until we monitor them. I've
built a few Heathkits but I'm no electronics tech or EE. Does anyone
have a temperature circuit that someone like myself can add to my EV to
display the controller surface temp? I was thinking of a thermistor
epoxied between the top fins with wire running to a meter in the cab.
Are there any other suggestions/ideas? I searched on the EVDL archives
and did not turn up much.

Has anyone tried to talk Curtis into adding an internal temperature
probe with external hookups to a remote meter?

Peter
JS
2008-07-13 22:22:21 UTC
Permalink
Peter Eckhoff wrote:
Does anyone
> have a temperature circuit that someone like myself can add to my EV to
> display the controller surface temp?

My Fluke Multimeter came with a thermocouple attachment that could
be used in a temporary hook-up. The Fluke also came with an
Infrared remote reading 'thermometer'.

> http://us.fluke.com/usen/products/ProductDetail.htm?cs_id=304%28FlukeProducts%29&catalog_name=FlukeUnitedStates&category=HMA(FlukeProducts)

Any cheap indoor-outdoor type thermometer has a remote sensor
that could be fastened to the heat-sink (with conductive grease),
and would give approximate temperatures, but may not have
enough range. The thermistor would probably go up farther than
the electronics.

I calibrated a thermistor using a coffee cup filled with cooking
oil on a hot-plate. Graphed temperature vs ohmmeter reading.
(Caution: Fire Hazard!)

John in Sylmar, CA
Drill now, pay through the nose later! (Or drive an EV!)
www.evalbum.com/1749
Glen Hoag
2008-07-13 22:42:56 UTC
Permalink
At 05:22 PM 7/13/2008, you wrote:

>I calibrated a thermistor using a coffee cup filled with cooking
>oil on a hot-plate. Graphed temperature vs ohmmeter reading.
>(Caution: Fire Hazard!)

There is a widely used third-order approximation of the response of
thermistors, the Steinhart-Hart
equation. <http://en.wikipedia.org/wiki/Steinhart-Hart_equation>
You only need temperature-resistance pairs at three points to derive
the coefficients to the equation. Typically, one uses the freezing
and boiling points of water; easily created at home with a coffee cup
calorimeter, and room temperature for the third point.

--Glen Hoag
hoag-***@public.gmane.org
Jeff Miller
2008-07-13 23:25:32 UTC
Permalink
http://www.canev.com/KitsComp/Components/1221C-1231C.pdf
That site includes a pretty decent drawing of the heatsink. It seems to me
someone with a Mill could make and market something better than what they
would sell us... If I only had a Mill.

-----Original Message-----
From: Peter Eckhoff [mailto:peckhoff-***@public.gmane.org]
Sent: Sunday, July 13, 2008 3:37 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Overheated 1231C - need for Temp circuit


Hello All,

The TEAA recently has had a go around on heat sinking our Curtis
controllers. The manual states: "Six mounting clamps are provided,
which can be used to attach the controller to its matching heatsink
(Curtis PMC p/n 16421001) or to some other surface. ... a thermal
compound can be used to improve heat conduction from the case to the
mounting surface."

A search on the Internet for p/n 16421001 (Google search: +Curtis
16421001) brings up **only** the quote from the Curtis manual and 2 porn
site links. Several parts houses recommend a flat sheet of 1/8"
aluminum with a tube of thermal compound. Several others on this list
have found finned heat sinks from heat sink suppliers. I've noticed the
most ardent supporters of finned heat sinks come from mainly pickup
truck drivers and drivers with heavy or poorly vented cars.

The Curtis controller is a sealed unit and is cooled by convection.
"The 1231C begins reducing power at 85 C (167F). Power output will be
reduced for as long as the overheat condition remains, and full power
will return when the unit cools."

We won't know how hot our controllers get until we monitor them. I've
built a few Heathkits but I'm no electronics tech or EE. Does anyone
have a temperature circuit that someone like myself can add to my EV to
display the controller surface temp? I was thinking of a thermistor
epoxied between the top fins with wire running to a meter in the cab.
Are there any other suggestions/ideas? I searched on the EVDL archives
and did not turn up much.

Has anyone tried to talk Curtis into adding an internal temperature
probe with external hookups to a remote meter?

Peter


_______________________________________________
For general EVDL support, see http://evdl.org/help/
For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
Bill Dennis
2008-07-14 00:10:13 UTC
Permalink
Jukka,
I'm really satisfied with my LCP cells in terms of energy content. I
think that my two parallel strings of 200Ah and 90Ah cells will allow me
to travel well over 100 miles per charge. But I'm really disappointed
in terms of power. I can't got above .3C without voltage really sagging
badly. So I have really poor acceleration and weak hill climbing
ability. I was wondering if you think things would improve if I
replaced the 90Ah string with the equivalent number of 60Ah LFP cells.

Thanks.

Bill Dennis
Neon John
2008-07-14 02:00:05 UTC
Permalink
On Sun, 13 Jul 2008 17:36:36 -0400, Peter Eckhoff <peckhoff-***@public.gmane.org> wrote:


>We won't know how hot our controllers get until we monitor them. I've
>built a few Heathkits but I'm no electronics tech or EE. Does anyone
>have a temperature circuit that someone like myself can add to my EV to
>display the controller surface temp? I was thinking of a thermistor
>epoxied between the top fins with wire running to a meter in the cab.
>Are there any other suggestions/ideas? I searched on the EVDL archives
>and did not turn up much.

I'm quite fond of the remote outdoor digital thermometers that can be had from
Wallyworld in the $10 range. The unit typically comes with a 10 ft cord but
can be extended any reasonable distance. The sensor is a 10k thermister so
lead resistance isn't a concern.

The sensor is typically embedded in a plastic blob about the size of a 1st
grade pencil lead. If that's too large then you can order a 10k thermister
from Digikey or equiv and replace it.

I've purchased a variety of these under various brand names, all of which seem
to operate the same way. Probably one of those universal chicom designs that
they'll put any private label on or case around.

They are extremely resistant to EMI. I've epoxied a sensor to a field winding
and another to a brush holder. In both cases, the thermometers worked without
problems.

The major limitation of a weather thermometer is that most top out at 120 to
140 degrees. If you need to measure something hotter than that then a digital
meat thermometer is the best choice for the dollar.

For example:

http://www.walmart.com/catalog/product.do?product_id=7894646

A nice feature of meat thermometers is that almost all of 'em have an
adjustable alarm to tell you when your meat (or controller) is done :-)

BTW, I caught this wireless unit

http://www.walmart.com/catalog/product.do?product_id=8467283

on closeout at Lowe's just before Christmas priced at $5 ea. I bought 'em all
:-) They made excellent Christmas presents. This is a very slick unit with a
range of over 300 yards. I can put a batch of meat on the smoker and wander
down to the general store across the community and still get a signal. I'm
not sure that I'd pay $60 for the thing but if it could be found cheaper....

>Has anyone tried to talk Curtis into adding an internal temperature
>probe with external hookups to a remote meter?

Not a chance. We're a tiny part of their market and for sure we're the only
ones who won't heat sink the thing as instructed. A fork lift manufacturer or
other commercial venture will over-engineer the cooling, if anything, to
ensure that there are no problems and to ensure long life.

Curtis's response would likely be "If you heat sink the controller according
to directions then there will be no overheating and therefore no external
sensor is necessary.

If Curtis DID agree to add a sensor, you can bet that it would cost more than
a $10 weather or meat thermometer!

John
--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
There are only 10 types of people in this world
Those who understand binary and those who don't.
Roger Stockton
2008-07-14 05:21:00 UTC
Permalink
Peter Eckhoff wrote:

> Does anyone have a temperature circuit that someone
> like myself can add to my EV to display the controller
> surface temp? I was thinking of a thermistor epoxied between
> the top fins with wire running to a meter in the cab.
> Are there any other suggestions/ideas?

A couple of thoughts for measuring the temp: if you have a DMM (or need an excuse to buy one ;^) with a thermocouple input/adapter, use that; or, take a thermistor (10K suggested) and monitor its resistance with a DMM. If your DMM has a min/max feature, you could use that to record the max/min temperatures during a trip. The mix/max function probably won't work on the resistance setting, so you'd have to connect the thermistor in series with another fixed resistor and connect the pair between 12V and ground so you can measure the voltage across the thermistor instead of the resistance. Choose the fixed resistor value to limit the current to a low enough value that the self-heating of the thermistor won't distort the readings too badly. Convert the voltage or resistance values to temper
atures later with the aid of a calculator or PC.

Regardless of the type of sensor you use, you don't want to loacate it at the top of the Curtis case. The internal heat spreader that the devices attach to bolts to the bottom of the case, and that is where the heat comes out. Ideally, you would get the sensor in contact with the base of the case, but the practical best might be to get it as near to the base of a side as possible.

Cheers,

Roger.
Toby B
2008-07-14 06:07:31 UTC
Permalink
Ah, buy your cheap Chinese stuff at
http://www.mpja.com/prodinfo.asp?number=16370+ME
and don't support Wal- Mart...

$4, and you need to solder an AA battery into it to power it
(the watch cell mounts are really junk)

However, the meter is adequate, and cheap enough that you could
use a few to see how hot your differential gets... motor, batteries, etc.

But I like disposable things like this because I often crunch them...

Toby

On Sun, Jul 13, 2008 at 10:21 PM, Roger Stockton <rstockton-***@public.gmane.org>
wrote:

> Peter Eckhoff wrote:
>
> > Does anyone have a temperature circuit that someone
> > like myself can add to my EV to display the controller
> > surface temp? I was thinking of a thermistor epoxied between
> > the top fins with wire running to a meter in the cab.
> > Are there any other suggestions/ideas?
>
Bill Dennis
2008-07-13 18:17:14 UTC
Permalink
Evan Tuer wrote:
> >Scenario 2: ...through the green wire back to the nearest supply point (where it's connected to the
> >white wire and the earth rod, as above).
>

> Okay, I think this is what I said in my previous post: the circuit is completed inside the house's breaker box through the white and green wire bars. Did I understand correctly?
>
Thanks.

Bill Dennis
Evan Tuer
2008-07-13 18:57:28 UTC
Permalink
On Sun, Jul 13, 2008 at 7:17 PM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
> Evan Tuer wrote:
>> >Scenario 2: ...through the green wire back to the nearest supply point (where it's connected to the
>> >white wire and the earth rod, as above).
>>
>
>> Okay, I think this is what I said in my previous post: the circuit is completed
> inside the house's breaker box through the white and green wire bars. Did I
> understand correctly?

You can assume the neutral wire is connected to ground somewhere, yes.
I doubt it's actually done in your breaker box.
The point is that both the neutral and ground wires (and the ground
itself) will act as a return path back to the transformer - the latter
two only in the case of a fault.
Neon John
2008-07-14 02:27:01 UTC
Permalink
On Sun, 13 Jul 2008 19:57:28 +0100, "Evan Tuer" <evan.tuer-***@public.gmane.org> wrote:


>You can assume the neutral wire is connected to ground somewhere, yes.
> I doubt it's actually done in your breaker box.
>The point is that both the neutral and ground wires (and the ground
>itself) will act as a return path back to the transformer - the latter
>two only in the case of a fault.

Per code here in the US, the ground and neutrals must be bonded in the main
panel (but not sub-panels). In most main panels, white and green wires are
interspersed on the same ground/neutral bus bar.

The concept of separate neutral and ground leads doesn't even exist upstream
of the breaker panel. Only three wires run back through the meter and to the
pole pig, the two hot legs and neutral. the neutral lug on the pig is bonded
to the grounded pig case and to a ground rod at the base of the pole (or a
ground cap on the end of the pole stuck in the ground. The equivalent
connections exist for pad-mounted transformers. And, of course, the
ground/neutral is grounded to a ground rod at the meter and/or at the main
panel.

Ground and neutral are for all practical purposes one and the same,
occasionally separated by a volt or two caused by the voltage drop through the
neutral conductor. That difference is insignificant and can be ignored when
analyzing this situation.

John
--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
Some people are only alive because it is illegal to kill.
Roland Wiench
2008-07-14 04:29:31 UTC
Permalink
The NEC now requires that the neutral and ground conductor not to be cross
connected between neutral bar and ground bar on a internal circuit breaker
panels.

We must now use a insulated neutral bar and separated ground bars that self
ground to the panel. We then run four conductors out to the meter base or
combination meter base. The neutral in the meter base has a buss bar
connected to the ground bar.

This ground bar is then connected to ground rod that the top of the rod must
be 6 inches below grade. A 3/4 inch PVC conduit is use to enclose the
ground wire that goes to the ground rod.

This PVC conduit is to provide mechanical protection and protect any person
from shock if the ground wire becomes disconnected from the ground rod.

In some states, they require to continue the ground wire out to the
transformer, either in overhead or underground and then the neutral and
ground is connected together at the transformer. There is a ground rod at
the transformer for the electrical ground, and there is a separated ground
rod for the lightning arrestors. We use to have all these tied together at
one time.

Roland


----- Original Message -----
From: "Neon John" <jgd-7o1kDznDRwqaMJb+***@public.gmane.org>
To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
Sent: Sunday, July 13, 2008 8:27 PM
Subject: Re: [EVDL] PFC-30 Tingle


> On Sun, 13 Jul 2008 19:57:28 +0100, "Evan Tuer" <evan.tuer-***@public.gmane.org>
> wrote:
>
>
> >You can assume the neutral wire is connected to ground somewhere, yes.
> > I doubt it's actually done in your breaker box.
> >The point is that both the neutral and ground wires (and the ground
> >itself) will act as a return path back to the transformer - the latter
> >two only in the case of a fault.
>
> Per code here in the US, the ground and neutrals must be bonded in the
> main
> panel (but not sub-panels). In most main panels, white and green wires
> are
> interspersed on the same ground/neutral bus bar.
>
> The concept of separate neutral and ground leads doesn't even exist
> upstream
> of the breaker panel. Only three wires run back through the meter and to
> the
> pole pig, the two hot legs and neutral. the neutral lug on the pig is
> bonded
> to the grounded pig case and to a ground rod at the base of the pole (or a
> ground cap on the end of the pole stuck in the ground. The equivalent
> connections exist for pad-mounted transformers. And, of course, the
> ground/neutral is grounded to a ground rod at the meter and/or at the main
> panel.
>
> Ground and neutral are for all practical purposes one and the same,
> occasionally separated by a volt or two caused by the voltage drop through
> the
> neutral conductor. That difference is insignificant and can be ignored
> when
> analyzing this situation.
>
> John
> --
> John De Armond
> See my website for my current email address
> http://www.neon-john.com
> http://www.johndearmond.com <-- best little blog on the net!
> Tellico Plains, Occupied TN
> Some people are only alive because it is illegal to kill.
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
Neon John
2008-07-14 07:25:42 UTC
Permalink
On Sun, 13 Jul 2008 22:29:31 -0600, "Roland Wiench" <ev_7-***@public.gmane.org> wrote:

>
>
>The NEC now requires that the neutral and ground conductor not to be cross
>connected between neutral bar and ground bar on a internal circuit breaker
>panels.
>
>We must now use a insulated neutral bar and separated ground bars that self
>ground to the panel. We then run four conductors out to the meter base or
>combination meter base. The neutral in the meter base has a buss bar
>connected to the ground bar.

That's kinda silly. Another case of the code, written by the manufacturers of
said hardware, being used to force-sell un-necessary hardware. That pretty
much describes all of Part 600.

Which revision of the code is that? It's not enforced here and the panels
available at our local supplier don't have separate buses. I think that we're
still at something like NEC 02 or thereabouts. I never bother to look since I
can simply ask the guy who's going to be inspecting the work what he wants to
see.

John
--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
There is much pleasure in useless knowledge. ?Bertrand Russell
Evan Tuer
2008-07-14 06:21:52 UTC
Permalink
On Mon, Jul 14, 2008 at 3:27 AM, Neon John <jgd-7o1kDznDRwqaMJb+***@public.gmane.org> wrote:
> On Sun, 13 Jul 2008 19:57:28 +0100, "Evan Tuer" <evan.tuer-***@public.gmane.org> wrote:
>
>
>>You can assume the neutral wire is connected to ground somewhere, yes.
>> I doubt it's actually done in your breaker box.
>>The point is that both the neutral and ground wires (and the ground
>>itself) will act as a return path back to the transformer - the latter
>>two only in the case of a fault.
>
> Per code here in the US, the ground and neutrals must be bonded in the main
> panel (but not sub-panels). In most main panels, white and green wires are
> interspersed on the same ground/neutral bus bar.
>
> The concept of separate neutral and ground leads doesn't even exist upstream
> of the breaker panel. Only three wires run back through the meter and to the
> pole pig, the two hot legs and neutral. the neutral lug on the pig is bonded
> to the grounded pig case and to a ground rod at the base of the pole (or a
> ground cap on the end of the pole stuck in the ground.

Ah, interesting. Here, the bonding is done at the "service entrance":
there's a tamper-proof main fuse block terminating the incoming
steel-wire-armoured cable, and the earth wire starts there. Two wires
run back to the transformer, and the neutral is connected to a ground
rod in the same way. The point is to use less wire anyway.

There are other schemes but that's the most common domestic one in the
UK (called TNCS). It does present a fun scenario where if only the
neutral wire going to the building is disconnected or cut, all the
metalwork in the house that's connected to it (radiators, electric
cars, etc) suddenly becomes live.

The regulation for campsites (RV parks) is different, you have to use
a (good) local earth spike - called TT earthing. So it's impossible
to get the above fault, and the likelyhood of the earth wire being
more than a few volts different to the ground you stand on is lower.
If I was going to install a dedicated EV charge point for public use,
I think that's probably a suitable example to follow.
redrocket
2008-07-13 18:32:00 UTC
Permalink
I have a basic question, When all of your batteries are connected, I
understand a single charger sends power to the pack as a whole, regardless
of the intividual batteries voltage or DoD. How do people monitor individual
batteries, while they are still in the pack?

In one example I was told a BMS was needed for each 4 cells. Again how does
it isolate it self from batteries down the line?

And finally, those who use several smaller chargers, do they need to
disconect bthat set of batteries from the rest?

Also, when doing an equilization charge, are individual, lower voltage
batteries removed and charged up to the standard, then replaced?

Thanks

marc
Roland Wiench
2008-07-13 16:02:57 UTC
Permalink
Hello Bill,

Only the green wire in the PFC is grounded to the enclosure. Back in the
50's we use the neutral (white) as the ground, but was found that in a 120
vac circuit, the neutral was also carrying current all the time, and
electrocuting people.

So the NEC mandated that a metal enclosure shall not continuous carry the
circuit all the time. So we remove the neutrals from the metal enclosures
and added a separated wire that is grounded to the enclosure, which we call
the ground (green wire).

Now any time one of the line wires (black or red) or call Line 1 or Line 2
shorts to a metal enclosure, this is the only time the the enclosure will
have this current flowing on it.

But the problem which was found, when someone is touching the grounded
enclosure and at the same time there was a short of the Line wires or even a
neutral wire to the metal enclosure, the person was electrocuted.

So the NEC made another change, which is normally found in new houses and
some old houses may not be up dated yet. The neutral and ground wire shall
not be connected together in a circuit breaker panel. The neutral bar is
now on a insulated base and there are separated ground bars.

We a one time cross connected the ground bar to neutral bar inside the
panel, but this was also change because you can get a circuit feed back, if
the ground wire connection to loose or broken between the panel ground bar
and the service entrance neutral.

So the NEC made another change where the neutral and ground will only be
made before it comes into the house or building. In a house, it is normally
done back at the meter base, and in some commercial and industrial areas,
that has isolation and explosive proof circuits. The neutral is grounded to
a 10 foot long electrode and the standard ground conductor is grounded to
another 10 foot electrode and then the ground rods are only connected to
connected about 6 feet depth below ground.

Isolated grounds have there own ground rod, plus two for lightning and
another for static.

Then the NEC made another change, where all receptacle circuits that are
located in the kitchen, bathroom, laundry rooms, dinettes, dining rooms,
garages, and outside locations shall be GFI protected either by a GFI
circuit breaker or GFI receptacle.

Roland




----- Original Message -----
From: "Bill Dennis" <wjdennis-r9/***@public.gmane.org>
To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
Sent: Sunday, July 13, 2008 9:26 AM
Subject: Re: [EVDL] PFC-30 Tingle


> I'm still not getting it. There must be a gap in my understanding.
>
> 1) When I touch the pack and the chassis, there is a path from the pack
> to the chassis through me.
> 2) There is a path from the chassis to the PFC-30's case
> 3) Under normal circumstances, there is no connection inside the PFC-30
> between the case and any other wire.
> 4) Green and white are connected back in the breaker box.
>
> So is the circuit completed by going back through the breaker box, then
> into the PFC-30 again through the white wire?
>
> Bill Dennis
joe
2008-07-13 23:20:44 UTC
Permalink
I confess, Bill, I have gotten bit, also - but i don't have a PFC-30, or any
PFC hooked up yet! The -20 hasn't been installed yet - but soon!

Joseph H. Strubhar

Web: www.gremcoinc.com

E-mail: joe-XfpEAlGaYgl8UrSeD/***@public.gmane.org
----- Original Message -----
From: "Bill Dennis" <wjdennis-r9/***@public.gmane.org>
To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
Sent: Sunday, July 13, 2008 7:28 AM
Subject: Re: [EVDL] PFC-30 Tingle


> Joe, I didn't do it on purpose! So I definitely need to be more
> careful. But I still didn't think there should be a path from the
> traction pack to the chassis.
>
> Bill Dennis
>
> joe wrote:
>> Just don't ever touch the connections with the charger on!!
>>
>> Joseph H. Strubhar
>>
>> Web: www.gremcoinc.com
>>
>> E-mail: joe-XfpEAlGaYgl8UrSeD/***@public.gmane.org
>> ----- Original Message -----
>> From: "Evan Tuer" <evan.tuer-***@public.gmane.org>
>> To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
>> Sent: Sunday, July 13, 2008 7:03 AM
>> Subject: Re: [EVDL] PFC-30 Tingle
>>
>>
>>
>>> On Sun, Jul 13, 2008 at 2:51 PM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
>>>
>>>> While the batteries were charging last night, something happened that I
>>>> thought wasn't supposed to occur. When the PFC-30 was charging, I
>>>> touched a cell terminal and the chassis at the same time. And I got
>>>> zapped.
>>>>
>>> Of course you will! The PFC chargers are not isolated. So the pack
>>> is electrically connected to the live wire of the supply. The live
>>> wire has a potential to ground, so you will get some fraction of that
>>> depending on where you made contact.
>>>
>>> This is why you should always use the following precautions:
>>> 1) always use a GFCI circuit breaker.
>>> 2) Insulate everything that is live when the charger is on.
>>> 3) if you're working on it with covers removed, insulate *yourself* -
>>> wear rubber gloves and boots as necessary, use insulated tools, and be
>>> careful.
>>>
>>> As an option, convert the supply to be isolated, using an isolation
>>> transformer (these are big and heavy, so you can't really take it with
>>> you). Or change to using an isolated charger if you can't avoid the
>>> risk sufficient with the above ideas.
>>>
>>>
>>> _______________________________________________
>>> For general EVDL support, see http://evdl.org/help/
>>> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>>>
>>>
>>> No virus found in this incoming message.
>>> Checked by AVG - http://www.avg.com
>>> Version: 8.0.138 / Virus Database: 270.4.10/1549 - Release Date:
>>> 7/12/2008
>>> 4:31 PM
>>>
>>>
>>>
>>>
>>
>>
>> _______________________________________________
>> For general EVDL support, see http://evdl.org/help/
>> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>>
>>
>>
>>
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
> No virus found in this incoming message.
> Checked by AVG - http://www.avg.com
> Version: 8.0.138 / Virus Database: 270.4.10/1550 - Release Date: 7/13/2008
> 5:58 PM
>
>
>
Bob Rice
2008-07-13 14:52:34 UTC
Permalink
----- Original Message -----
From: "joe" <joe-XfpEAlGaYgl8UrSeD/***@public.gmane.org>
To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
Sent: Sunday, July 13, 2008 10:21 AM
Subject: Re: [EVDL] PFC-30 Tingle


> Just don't ever touch the connections with the charger on!!
>
> Joseph H. Strubhar

He EVerybody;

No true-er statement! Think working on the RR, ya DON'T touch the 3rd
rail, the're only 600 volts. ether!Oh ya CAN IF you are in DRY rubber shoes,
NOT touching the car body, ect Or check yur batterie in bare feet!!Or lean
on the body while opening the caps to check if you have any water?It's
tricky doing Show an' Tell with A PFC at full bore!Like "Hands Off!"
Common, carefull commen sense, But we ALL have been bitten! Hell! It's like
just reaching into yur electrical box and grabbing anything that looks
appealing. I wouldn't let my grandkids NEAR that!!!!!!!!!!!!!!!Ether Or!
This is the risk ya take, as David R. points out, but, we KNOW better? Just
keep AWAY from Hot Stuff! Don't walk against the Red, play on the RR trax
when the Acela's due. Look BOTH ways before crossing the street, one of them
hybrids could sneak up on ya!

Seeya

Bob
Roland Wiench
2008-07-13 15:20:32 UTC
Permalink
Hello Bill,

All you have to do is run a isolated ground system. This means that the
device grounding is not connected to vehicle chassis.

In building electrical, we do this all the time. We run isolated grounding
circuits where the conduit or enclosures are not at the same grounding
potential as the circuit ground.

Example: Installing isolated receptacle devices on 120 VAC, we may use a
neutral (white), line (L1), (black) and a isolated ground wire which is
green with a yellow tracer.

The isolated receptacle ground terminal connection is not connected to the
holding strap like a standard receptacle. Using a standard grounded
receptacle, it self grounds to a steel junction box and conduits.

Two ways to make your PFC charger isolated from the EV chassis, is either
have the charger outboard and just plug in DC power. The batteries should
be setting in a non-conductive container, so there is no conductive path of
the battery cases.

Any time you charge a battery, it may vent and increases the the conductive
path from the battery case, to the battery enclosure or box and than to the
EV body it self.

Another way to isolated the PFC enclosure while it is mounted in the
vehicle, is set it on a non-conductive isolation board or enclosure. You
still have the charger enclosure ground and the circuitry is the same as if
the charger was outboard setting on a bench which is not making contact with
the EV frame or body.

Rich Rudman has advise to put the charger on a insulated board when mounting
in the EV.

In a isolated circuit installation, we may install a ground detection
circuit which is not like a GFI circuit. This circuit detects if the
isolated grounded chassis is shorted to a standard grounded chassis, and it
alerts the operators before starting up the equipment.

This method is use in explosive proof areas, and is use in isolated and arc
proof devices in operating rooms.

A simple means of detecting this is to have a panel mounted volt meter in
the 200 ma range or even a ohm meter that is connected between the charger
enclosure which was made isolated and the body of the EV.

You first turn on the meter indicator circuit before you turn on the charger
to see if there is any circuit conductance. Then you can turn off the ohm
meter if using one and leave on the volt meter.

The commercial ground detection devices we use are very costly to use in a
EV. They detect single, two, and three phase differences and may shut down
the main power entering the area by the use of large magnetic contactors.

You could also use a GFI circuit breaker, which is a panel mounted one in
the EV, that is between the AC input plug and the charger or any other tap
off circuits you may have. This is what I have. You can use a standard GFI
plug circuit breaker that normally plugs into a circuit breaker panel, but
you get a circuit breaker mounting base that mounts on a chassis board.

You can also get this breaker with Line and Load wire lugs, and this uses on
metal clips to mounted it to a board.

Your batteries should be dead fronted, meaning it is enclose and cover.
This is the same with circuit breakers panels and switch boards, we do not
leave them open. You have to treat the battery installation the same way.

Roland


----- Original Message -----
From: "Bill Dennis" <wjdennis-r9/***@public.gmane.org>
To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
Sent: Sunday, July 13, 2008 7:51 AM
Subject: [EVDL] PFC-30 Tingle


> While the batteries were charging last night, something happened that I
> thought wasn't supposed to occur. When the PFC-30 was charging, I
> touched a cell terminal and the chassis at the same time. And I got
> zapped. I did some testing with the voltmeter, and found that when the
> PFC-30 is off, there is no voltage between the traction pack and the
> chassis. But when the PFC-30 is on, one end of the traction pack has
> +60V to the chassis, and the other end of the traction pack has -60V to
> the chassis. This was while charging from the 240V AC mains. The
> PFC-30's green grounding wire, as well as its case, are connected to the
> chassis, per the instructions in Manzanita's manual. I think Don
> Cameron had this same problem a few years ago, but I don't know if he
> ever got it resolved. Any suggestions?
>
> Bill Dennis
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
Bill Dennis
2008-07-13 16:01:01 UTC
Permalink
Roland Wiench wrote:

>Rich Rudman has advise to put the charger on a insulated board when
mounting
>in the EV.

Roland, is this something that he has said online, because here's what's
written in the manual:

"Connect the green lead of the charge cable to the chassis of the vehicle."

Bill Dennis
> Hello Bill,
>
> All you have to do is run a isolated ground system. This means that the
> device grounding is not connected to vehicle chassis.
>
> In building electrical, we do this all the time. We run isolated grounding
> circuits where the conduit or enclosures are not at the same grounding
> potential as the circuit ground.
>
> Example: Installing isolated receptacle devices on 120 VAC, we may use a
> neutral (white), line (L1), (black) and a isolated ground wire which is
> green with a yellow tracer.
>
> The isolated receptacle ground terminal connection is not connected to the
> holding strap like a standard receptacle. Using a standard grounded
> receptacle, it self grounds to a steel junction box and conduits.
>
> Two ways to make your PFC charger isolated from the EV chassis, is either
> have the charger outboard and just plug in DC power. The batteries should
> be setting in a non-conductive container, so there is no conductive path of
> the battery cases.
>
> Any time you charge a battery, it may vent and increases the the conductive
> path from the battery case, to the battery enclosure or box and than to the
> EV body it self.
>
> Another way to isolated the PFC enclosure while it is mounted in the
> vehicle, is set it on a non-conductive isolation board or enclosure. You
> still have the charger enclosure ground and the circuitry is the same as if
> the charger was outboard setting on a bench which is not making contact with
> the EV frame or body.
>
> Rich Rudman has advise to put the charger on a insulated board when mounting
> in the EV.
>
> In a isolated circuit installation, we may install a ground detection
> circuit which is not like a GFI circuit. This circuit detects if the
> isolated grounded chassis is shorted to a standard grounded chassis, and it
> alerts the operators before starting up the equipment.
>
> This method is use in explosive proof areas, and is use in isolated and arc
> proof devices in operating rooms.
>
> A simple means of detecting this is to have a panel mounted volt meter in
> the 200 ma range or even a ohm meter that is connected between the charger
> enclosure which was made isolated and the body of the EV.
>
> You first turn on the meter indicator circuit before you turn on the charger
> to see if there is any circuit conductance. Then you can turn off the ohm
> meter if using one and leave on the volt meter.
>
> The commercial ground detection devices we use are very costly to use in a
> EV. They detect single, two, and three phase differences and may shut down
> the main power entering the area by the use of large magnetic contactors.
>
> You could also use a GFI circuit breaker, which is a panel mounted one in
> the EV, that is between the AC input plug and the charger or any other tap
> off circuits you may have. This is what I have. You can use a standard GFI
> plug circuit breaker that normally plugs into a circuit breaker panel, but
> you get a circuit breaker mounting base that mounts on a chassis board.
>
> You can also get this breaker with Line and Load wire lugs, and this uses on
> metal clips to mounted it to a board.
>
> Your batteries should be dead fronted, meaning it is enclose and cover.
> This is the same with circuit breakers panels and switch boards, we do not
> leave them open. You have to treat the battery installation the same way.
>
> Roland
>
>
> ----- Original Message -----
> From: "Bill Dennis" <wjdennis-r9/***@public.gmane.org>
> To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
> Sent: Sunday, July 13, 2008 7:51 AM
> Subject: [EVDL] PFC-30 Tingle
>
>
>
>> While the batteries were charging last night, something happened that I
>> thought wasn't supposed to occur. When the PFC-30 was charging, I
>> touched a cell terminal and the chassis at the same time. And I got
>> zapped. I did some testing with the voltmeter, and found that when the
>> PFC-30 is off, there is no voltage between the traction pack and the
>> chassis. But when the PFC-30 is on, one end of the traction pack has
>> +60V to the chassis, and the other end of the traction pack has -60V to
>> the chassis. This was while charging from the 240V AC mains. The
>> PFC-30's green grounding wire, as well as its case, are connected to the
>> chassis, per the instructions in Manzanita's manual. I think Don
>> Cameron had this same problem a few years ago, but I don't know if he
>> ever got it resolved. Any suggestions?
>>
>> Bill Dennis
>>
>>
>> _______________________________________________
>> For general EVDL support, see http://evdl.org/help/
>> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>>
>>
>>
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
>
>
Evan Tuer
2008-07-13 16:09:17 UTC
Permalink
On Sun, Jul 13, 2008 at 5:01 PM, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:
> Roland Wiench wrote:
>
> >Rich Rudman has advise to put the charger on a insulated board when
> mounting
> >in the EV.
>
> Roland, is this something that he has said online, because here's what's
> written in the manual:

Yes. Rich apparently does or did this. We used to argue about it
about every 6 months. I think the conclusion we reached was that
sensibly, he wasn't actually advising anyone else to do it - but he
knows what he's doing and has a particular set of circumstances and a
risk that's acceptable to him. Which is fine.

Everyone else should pay attention to the advice given in the manual,
and on this list, unless you *really* know what you're doing! :)
Roland Wiench
2008-07-13 16:17:35 UTC
Permalink
Hello Bill,

We had this same discussion several years ago, and Rich said, just install
the PFC on a insulator board to isolated from the EV. It then becomes just
like a charger setting on a bench outside the vehicle.

Now, you can still get shock, by touching any one of the battery post and
standing bare foot on a wet ground that may complete a ground path to a
ground rod that is use for that building. You then completed a circle or a
circuit.

This path is now through the ground and not through the EV at this time
which is more resistance.

If you are use a GFIC device, and it did not trip, it may because it still
detected the current in the safe zone. I would test out the GFIC 120 volt
device which is done by shorting the neutral wire to a ground wire while the
internal circuit has some load on it. This is done by pressing the
test/reset button.

Roland


----- Original Message -----
From: "Bill Dennis" <wjdennis-r9/***@public.gmane.org>
To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
Sent: Sunday, July 13, 2008 10:01 AM
Subject: Re: [EVDL] PFC-30 Tingle


> Roland Wiench wrote:
>
> >Rich Rudman has advise to put the charger on a insulated board when
> mounting
> >in the EV.
>
> Roland, is this something that he has said online, because here's what's
> written in the manual:
>
> "Connect the green lead of the charge cable to the chassis of the
> vehicle."
>
> Bill Dennis
> > Hello Bill,
> >
> > All you have to do is run a isolated ground system. This means that the
> > device grounding is not connected to vehicle chassis.
> >
> > In building electrical, we do this all the time. We run isolated
> > grounding
> > circuits where the conduit or enclosures are not at the same grounding
> > potential as the circuit ground.
> >
> > Example: Installing isolated receptacle devices on 120 VAC, we may use
> > a
> > neutral (white), line (L1), (black) and a isolated ground wire which is
> > green with a yellow tracer.
> >
> > The isolated receptacle ground terminal connection is not connected to
> > the
> > holding strap like a standard receptacle. Using a standard grounded
> > receptacle, it self grounds to a steel junction box and conduits.
> >
> > Two ways to make your PFC charger isolated from the EV chassis, is
> > either
> > have the charger outboard and just plug in DC power. The batteries
> > should
> > be setting in a non-conductive container, so there is no conductive path
> > of
> > the battery cases.
> >
> > Any time you charge a battery, it may vent and increases the the
> > conductive
> > path from the battery case, to the battery enclosure or box and than to
> > the
> > EV body it self.
> >
> > Another way to isolated the PFC enclosure while it is mounted in the
> > vehicle, is set it on a non-conductive isolation board or enclosure.
> > You
> > still have the charger enclosure ground and the circuitry is the same as
> > if
> > the charger was outboard setting on a bench which is not making contact
> > with
> > the EV frame or body.
> >
> > Rich Rudman has advise to put the charger on a insulated board when
> > mounting
> > in the EV.
> >
> > In a isolated circuit installation, we may install a ground detection
> > circuit which is not like a GFI circuit. This circuit detects if the
> > isolated grounded chassis is shorted to a standard grounded chassis, and
> > it
> > alerts the operators before starting up the equipment.
> >
> > This method is use in explosive proof areas, and is use in isolated and
> > arc
> > proof devices in operating rooms.
> >
> > A simple means of detecting this is to have a panel mounted volt meter
> > in
> > the 200 ma range or even a ohm meter that is connected between the
> > charger
> > enclosure which was made isolated and the body of the EV.
> >
> > You first turn on the meter indicator circuit before you turn on the
> > charger
> > to see if there is any circuit conductance. Then you can turn off the
> > ohm
> > meter if using one and leave on the volt meter.
> >
> > The commercial ground detection devices we use are very costly to use in
> > a
> > EV. They detect single, two, and three phase differences and may shut
> > down
> > the main power entering the area by the use of large magnetic
> > contactors.
> >
> > You could also use a GFI circuit breaker, which is a panel mounted one
> > in
> > the EV, that is between the AC input plug and the charger or any other
> > tap
> > off circuits you may have. This is what I have. You can use a standard
> > GFI
> > plug circuit breaker that normally plugs into a circuit breaker panel,
> > but
> > you get a circuit breaker mounting base that mounts on a chassis board.
> >
> > You can also get this breaker with Line and Load wire lugs, and this
> > uses on
> > metal clips to mounted it to a board.
> >
> > Your batteries should be dead fronted, meaning it is enclose and cover.
> > This is the same with circuit breakers panels and switch boards, we do
> > not
> > leave them open. You have to treat the battery installation the same
> > way.
> >
> > Roland
> >
> >
> > ----- Original Message -----
> > From: "Bill Dennis" <wjdennis-r9/***@public.gmane.org>
> > To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
> > Sent: Sunday, July 13, 2008 7:51 AM
> > Subject: [EVDL] PFC-30 Tingle
> >
> >
> >
> >> While the batteries were charging last night, something happened that I
> >> thought wasn't supposed to occur. When the PFC-30 was charging, I
> >> touched a cell terminal and the chassis at the same time. And I got
> >> zapped. I did some testing with the voltmeter, and found that when the
> >> PFC-30 is off, there is no voltage between the traction pack and the
> >> chassis. But when the PFC-30 is on, one end of the traction pack has
> >> +60V to the chassis, and the other end of the traction pack has -60V to
> >> the chassis. This was while charging from the 240V AC mains. The
> >> PFC-30's green grounding wire, as well as its case, are connected to
> >> the
> >> chassis, per the instructions in Manzanita's manual. I think Don
> >> Cameron had this same problem a few years ago, but I don't know if he
> >> ever got it resolved. Any suggestions?
> >>
> >> Bill Dennis
> >>
> >>
> >> _______________________________________________
> >> For general EVDL support, see http://evdl.org/help/
> >> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
> >>
> >>
> >>
> >
> >
> > _______________________________________________
> > For general EVDL support, see http://evdl.org/help/
> > For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
> >
> >
> >
> >
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
Evan Tuer
2008-07-13 16:28:28 UTC
Permalink
On Sun, Jul 13, 2008 at 5:17 PM, Roland Wiench <ev_7-***@public.gmane.org> wrote:

Hi Roland,

> Now, you can still get shock, by touching any one of the battery post and
> standing bare foot on a wet ground that may complete a ground path to a
> ground rod that is use for that building.

You don't need to be barefoot on wet ground. I've had a bad shock off
a non-isolated EV charger (not a Manzanita one!) wearing synthetic
training shoes and standing on dry gravel. That was an accident too,
but I've not done it again!
Bob Rice
2008-07-13 16:53:09 UTC
Permalink
----- Original Message -----
From: "Evan Tuer" <evan.tuer-***@public.gmane.org>
To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
Sent: Sunday, July 13, 2008 12:28 PM
Subject: Re: [EVDL] PFC-30 Tingle


> On Sun, Jul 13, 2008 at 5:17 PM, Roland Wiench <ev_7-***@public.gmane.org> wrote:
>
> Hi Roland,
>
>> Now, you can still get shock, by touching any one of the battery post and
>> standing bare foot on a wet ground that may complete a ground path to a
>> ground rod that is use for that building.
>
> You don't need to be barefoot on wet ground. I've had a bad shock off
> a non-isolated EV charger (not a Manzanita one!) wearing synthetic
> training shoes and standing on dry gravel. That was an accident too,
> but I've not done it again!
>
> Yup! Bitten once, all that.(May, he sez!?) It would be as effective as an
> electric chair to touch things, were talking about, in USA, with bare feet
> on wet ground!!!!! We have grounding rods and a code that is constantly
> changing to try to make it safer? GAS is more dangerous, but we take
> proper precautions gassing our gas rigs! Thinlk of the carnage that you
> could do in a self serv. gas station with a nozzle and a cigerette
> lighter!?

Seeya

Bob
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
JS
2008-07-13 17:01:24 UTC
Permalink
I thought I was safe with rubber-soled shoes,
on dry concrete. I did not count on a nail
that had punched through the heal as it wore
down. OUCH!

I don't think they use nails in shoes any more.

That lesson probably saved my life a dozen times!

John in Sylmar, CA
www.evalbum.com/1749
Neon John
2008-07-14 07:29:28 UTC
Permalink
On Sun, 13 Jul 2008 10:01:24 -0700, JS <za145-***@public.gmane.org> wrote:

>I thought I was safe with rubber-soled shoes,
>on dry concrete. I did not count on a nail
>that had punched through the heal as it wore
>down. OUCH!
>
>I don't think they use nails in shoes any more.
>
>That lesson probably saved my life a dozen times!

Even nail-less rubber soled shoes aren't safe unless they're specifically
designated as dielectric soles.

Most shoe manufacturers have been making sole rubber semi-conductive for a
long time to eliminate static shock from walking across carpets.

I just checked both pairs of sneakers that I own, one a fairly spendy pair of
Newbalance Walkers and the other a pair of $18 wallyworld specials. Using a
digital megger, I placed one probe at the toe and another at the heel.

Both read identically, 4 megohms, plus or minus at 500 test volts and "zero"
megohms (less than 1 megohm, as the minimum resolution is 1 megohm on that
scale) at 1000 test volts. I've been lazing around the house today in my
house shoes so neither pair have any sweat inside. Nonetheless, both showed
about 4 megohms of conductivity at 1000 volts between the inner and outer
sole. Had they been moist with sweat, that would no doubt been much lower.
These tests were with test probes making point-contact with the rubber. An
area contact between the sole and concrete would show much less resistance.

I always consider sneaker soles to be conductive and take precautions
accordingly. That includes a rubber insulating mat on the concrete floor in
front of my breaker panel. That's probably saved my life on multiple
occasions, as I know that I've let the back of my hand or a knuckle brush a
conductor on more than one occasion. Not even a tingle.

John


--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
Beware the lollipop of mediocrity. Lick once and you suck forever.
Roland Wiench
2008-07-13 17:03:40 UTC
Permalink
Hello Evan,

You must be at a lower resistance than I am. I can hold on to a 120V and
even a 240V wire and may not feel it. I can squeeze the wire harder and
still cannot feel it at 120V, but some at 240V.

It is very common for our electrical workers to stick there fingers in a
lamp socket to see if there is any current and some of the guys can change
receptacles and switches while they are hot.

Now if I lick my fingers (only using one hand) I now can barely feel the
120V. Remember not put your whole body in series, I do this by shunting my
body between two fingers on one hand.

Of course, I am wearing linemen boots, no watches, no rings, or any metal
objects and 100 percent cotton clothes which are static free.

Roland

R


----- Original Message -----
From: "Evan Tuer" <evan.tuer-***@public.gmane.org>
To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
Sent: Sunday, July 13, 2008 10:28 AM
Subject: Re: [EVDL] PFC-30 Tingle


> On Sun, Jul 13, 2008 at 5:17 PM, Roland Wiench <ev_7-***@public.gmane.org> wrote:
>
> Hi Roland,
>
> > Now, you can still get shock, by touching any one of the battery post
> > and
> > standing bare foot on a wet ground that may complete a ground path to a
> > ground rod that is use for that building.
>
> You don't need to be barefoot on wet ground. I've had a bad shock off
> a non-isolated EV charger (not a Manzanita one!) wearing synthetic
> training shoes and standing on dry gravel. That was an accident too,
> but I've not done it again!
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
joe
2008-07-13 23:27:55 UTC
Permalink
LOL, Roland - you sound like my dad! He could take hold of live wires and
just feel maybe a little tickle, because of the many thick calluses on his
fingers!

Joseph H. Strubhar

Web: www.gremcoinc.com

E-mail: joe-XfpEAlGaYgl8UrSeD/***@public.gmane.org
----- Original Message -----
From: "Roland Wiench" <ev_7-***@public.gmane.org>
To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
Sent: Sunday, July 13, 2008 10:03 AM
Subject: Re: [EVDL] PFC-30 Tingle


> Hello Evan,
>
> You must be at a lower resistance than I am. I can hold on to a 120V and
> even a 240V wire and may not feel it. I can squeeze the wire harder and
> still cannot feel it at 120V, but some at 240V.
>
> It is very common for our electrical workers to stick there fingers in a
> lamp socket to see if there is any current and some of the guys can change
> receptacles and switches while they are hot.
>
> Now if I lick my fingers (only using one hand) I now can barely feel the
> 120V. Remember not put your whole body in series, I do this by shunting
> my body between two fingers on one hand.
>
> Of course, I am wearing linemen boots, no watches, no rings, or any metal
> objects and 100 percent cotton clothes which are static free.
>
> Roland
>
> R
>
>
> ----- Original Message -----
> From: "Evan Tuer" <evan.tuer-***@public.gmane.org>
> To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
> Sent: Sunday, July 13, 2008 10:28 AM
> Subject: Re: [EVDL] PFC-30 Tingle
>
>
>> On Sun, Jul 13, 2008 at 5:17 PM, Roland Wiench <ev_7-***@public.gmane.org> wrote:
>>
>> Hi Roland,
>>
>> > Now, you can still get shock, by touching any one of the battery post
>> > and
>> > standing bare foot on a wet ground that may complete a ground path to a
>> > ground rod that is use for that building.
>>
>> You don't need to be barefoot on wet ground. I've had a bad shock off
>> a non-isolated EV charger (not a Manzanita one!) wearing synthetic
>> training shoes and standing on dry gravel. That was an accident too,
>> but I've not done it again!
>>
>>
>> _______________________________________________
>> For general EVDL support, see http://evdl.org/help/
>> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>>
>>
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
> No virus found in this incoming message.
> Checked by AVG - http://www.avg.com Version: 8.0.138 / Virus Database:
> 270.4.10/1550 - Release Date: 7/13/2008 5:58 PM
>
>
>
Neon John
2008-07-14 02:34:27 UTC
Permalink
On Sun, 13 Jul 2008 10:01:01 -0600, Bill Dennis <wjdennis-r9/***@public.gmane.org> wrote:

>Roland Wiench wrote:
>
> >Rich Rudman has advise to put the charger on a insulated board when
>mounting
> >in the EV.
>
>Roland, is this something that he has said online, because here's what's
>written in the manual:
>
>"Connect the green lead of the charge cable to the chassis of the vehicle."

This is correct and it would be slightly insane, not to mention against code,
to do otherwise. If your car body isn't grounded and a leakage path exists
between the traction system and the car body, then when the PFC is connected,
there exists a direct path from the line, through the charger and through the
leakage to the car body. The car body is now hot and when you touch it you
get zapped. The car body MUST be grounded when using a PFC unless you're
using an isolation transformer ahead of the PFC.

John
--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
Serenity: That feeling of knowing that your secretary will never tell either of your wives.
Roland Wiench
2008-07-14 04:02:58 UTC
Permalink
Hello John,

This is true if you bolt the PFC to the body or frame of the EV and the
batteries are setting in a open steel rack which is also bolt to the EV
frame. My is not like that.

My PFC charger is setting inside a 1/4 inch thick epoxy coated enclosure
where only the charger box is ground. It is isolated from the EV body and
frame.

When you have a outboard charger, there is only two DC lines going to a
Anderson DC input plug. There is no AC ground wire that is connected to the
EV with this type of input circuit.

The on board charger has a additional GFI circuit breaker is install between
a polorize nylon totally enclose connector and plug. THIS IS NOT A SELF
GROUNDING RECEPTACLE, but a isolation type of plug and connector.

The main contactor and motor controller is also isolated from the battery by
the use of two large safety contactors while the batteries are being charge,
or you will the charging voltage at the controller and in some controller
circuits, one dc line goes through a shunt right to the motor.

The motor then can leak the charging current to the EV frame by the
conductive path of the brush dust which has happen to some of the people on
this list.

My batteries are also install in a epoxy coated 1/4 inch thick fiberglass
box which is cover with 2 inches of foam and nylon and then there is another
layer of nylon and 2 inch foam that insulates and separates the batteries
from the steel EV body.

I been running this ground isolation circuit for 28 years now with no
problem. The only leakage I get is across the top of the batteries when
they are venting. When this leakage gets up to 0.1 volt or so, then its
time to clean the batteries.

Roland


----- Original Message -----
From: "Neon John" <jgd-7o1kDznDRwqaMJb+***@public.gmane.org>
To: "Electric Vehicle Discussion List" <ev-UWgVIey+***@public.gmane.org>
Sent: Sunday, July 13, 2008 8:34 PM
Subject: Re: [EVDL] PFC-30 Tingle


> On Sun, 13 Jul 2008 10:01:01 -0600, Bill Dennis <wjdennis-r9/***@public.gmane.org>
> wrote:
>
> >Roland Wiench wrote:
> >
> > >Rich Rudman has advise to put the charger on a insulated board when
> >mounting
> > >in the EV.
> >
> >Roland, is this something that he has said online, because here's what's
> >written in the manual:
> >
> >"Connect the green lead of the charge cable to the chassis of the
> >vehicle."
>
> This is correct and it would be slightly insane, not to mention against
> code,
> to do otherwise. If your car body isn't grounded and a leakage path
> exists
> between the traction system and the car body, then when the PFC is
> connected,
> there exists a direct path from the line, through the charger and through
> the
> leakage to the car body. The car body is now hot and when you touch it
> you
> get zapped. The car body MUST be grounded when using a PFC unless you're
> using an isolation transformer ahead of the PFC.
>
> John
>
Neon John
2008-07-14 07:25:39 UTC
Permalink
On Sun, 13 Jul 2008 22:02:58 -0600, "Roland Wiench" <ev_7-***@public.gmane.org> wrote:

>Hello John,
>
>This is true if you bolt the PFC to the body or frame of the EV and the
>batteries are setting in a open steel rack which is also bolt to the EV
>frame. My is not like that.

But the problem remains that if some path develops between your pack or any of
the traction wiring and the car body, there is a direct path from the line,
through the charger, through the wiring/body fault and to the body. The body
is then hot.

Hopefully the GFI in the charger will work but I'd not bet my life on it. It
apparently didn't work in Bruce's case. Since a car body ground is so easy to
apply, I just don't see the case for not doing it.

An off-board charger, assuming we're talking about an isolated charger like
with a fork lift, is a different matter. It's designed to be isolated. Many
have internal ground fault detecting circuitry and many get routine Hi-Pot
testing. Different class of equipment and the price reflects it.

John
--
John De Armond
See my website for my current email address
http://www.neon-john.com
http://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
There is much pleasure in useless knowledge. ?Bertrand Russell
EVDL Administrator
2008-07-14 06:19:00 UTC
Permalink
I'm not quite sure how to say this so as not to sound like I'm dumping on
the PFC chargers. They do have their place, but I've always had some
concern about them.

When they were under design, the builder asked EVDL members what they wanted
in a charger. He did do some prompting, but it was still pretty clear that
a fairly low cost was important. Input voltage flexibility was an interest,
and so was lots of charging power.

For most EVDLers, safety wasn't much of a consideration, as I recall. I was
one of the few people who suggested that the PFC should be an isolated
design. However, isolation would have added quite a bit to the price, so it
wasn't included. Making it an option has since been discussed but I think
with very little interest expressed from the (hobbyist) customers.

So, basically, the PFC chargers are optimized for the maximum charging
output per dollar. Safety (and charge control) are further down the list of
priorities.

None of this is a secret. Look at the charger. Do you see a UL or CSA mark
on it? No. It hasn't been submitted for testing nor has it been designed
to comply with UL and/or CSA requirements. It might comply if tested, but
that wasn't an objective. This pretty well limits the PFC chargers to EV
hobbyists. I remember seeing non-UL chargers in commercial conversions 20
years ago, but today I think it's much less likely. Too legally risky.
Heck, that was probably true even then; don't tell Chandler Waterman. ;-)

I'm not going to call the PFC unsafe, but I think it's fair to say that a
fully isolated charger IS safer.

I personally would like to see more of an emphasis on safety in hobbyist
EVs. I have some concerns about what the news media would do with a 5 year
old kid electrocuted by a homebrew EV charging in the driveway, and what the
result would be for the hobbyist EV movement. However, when I've brought
that up here in the past I've been (virtually ;-) beaten about the head and
shoulders with a blunt instrument. And, maybe I >am< being overly cautious.
So I won't get into the graphic detail this time. ;-)

Still, if safety is important to you, then for goodness sake, buy an
isolated charger. Zivan and Brusa are examples. In lower voltages, Delta-
Q is another (you could use two of them for higher voltages). Even an old
golf car charger will be isolated. Or buy an isolation transformer (though
it'll be heavy).

If you decide to change to a safer charger, I'm sure you'll be able to find
someone who will take the PFC off your hands. AFAIK, they continue to be in
demand among EV hobbyists.

David Roden - Akron, Ohio, USA
EVDL Administrator

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Jeff Shanab
2008-07-12 20:24:56 UTC
Permalink
I just remembered a program I use to monitor machine performance called
munin.
There is a how-to on how to write a module and we could probably use or
modify the LM Sensors (I2C) module.

Anyway the data collecting unit runs munin-node(very small) and your
desktop would run the munin server which polls the information, writes
it into a database and generates web pages of graphs.

As this is getting a little OT, contact me off list for furthors.
Jeff Shanab
2008-07-12 20:39:12 UTC
Permalink
> Doug Weathers wrote:
> redrocket wrote:
>>> thinking about a nice front end touch screen computer in the car.
>
> I know touch screens are a popular idea; but are you sure that's what
> you want the driver to be using? They require a significant amount of
> time with your eyes off the road.
>
> Our Toyota Prius has a touchscreen. I find it very distracting, and
> almost dangerous to use while driving.

Absolutly agree, lining the borders with tactile buttons are better.
See the twidler idea here, i wonder if this would be better.
(Dash-PC has solved a lot of these issues) http://www.dashpc.com/
(look at steering column control in album)
>
>> I know, with the limited range of the usual EV a navigation system
>> is kind of silly. But it's probably doable.
>
> Actually, it can be handy. My old ComutaVan could barely do 55 mph, so
> freeway use was only safe during "rush hour" when the actual speeds
> were very slow. So, I normally used side roads and residential
> streets. A good NAV system could be a big help.
>
>>> and since it has built in wifi, when you park it in the garage at home,
>>> you could access all the data on your PC wirelessly.
>
> That's a useful feature.
I was thinking of buying a linksys broadband router/wireless access
point program it to serve out your web pages.
>
>>> What monitoring hardware, circuitry, would you need to measure, these
>>> variables and then send them via USB to the Itouch?
>
> Perhaps the most straightforward method is to get a multimeter with
> serial USB or RS-232 interface. It can be set to measure almost anything.
>
>> There are probably dozens of choices for the car computer, with wide
>> ranges of price and capability.
>
> Yes. The big challenge to find something that will actually survive in
> an automotive environment. If you live in a place that doesn't have
> weather, lots of indoor electronics will do. But if they have to
> contend with extreme temperatures, condensation, bugs, etc. it will be
> more difficult.
It was 112 Degrees today, the cars get really hot inside.
>
> --
> Ring the bells that still can ring
> Forget the perfect offering
> There is a crack in everything
> That's how the light gets in -- Leonard Cohen
> --
> Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
Chip Gribben
2008-07-13 19:33:10 UTC
Permalink
Bill, another fan may not be enough. It sounds like you need to
dissipate the heat off the controller.

If you mount the controller on an aluminum plate with some heat sink
grease that may help.

I've seen finned heat sinks for Curtis controllers from KTA several
years ago. Not sure if they are available anymore or not. But a piece
of aluminum and if possible mounting the controller in the airflow
together should help. Although sometimes you are stuck with where the
controller is so natural airflow is not always available.

The fans should help but dissipating the heat with a heatsink will
also help even more.

To take it one step further, which will involve alot more work is
building a heatsink with a built in radiator to run some coolant
through it. I haven't gone to that extreme yet but have seen people
do that.

Chip




On Jul 13, 2008, at 3:00 PM, ev-request-UWgVIey+***@public.gmane.org wrote:

> Message: 13
> Date: Sun, 13 Jul 2008 12:14:46 -0600
> From: Bill Dennis <wjdennis-r9/***@public.gmane.org>
> Subject: [EVDL] Overheated 1231C
> To: Electric Vehicle Discussion List <ev-UWgVIey+***@public.gmane.org>
> Message-ID: <487A4616.6000301-r9/***@public.gmane.org>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> I think I overheated the Curtis 1231C today. I took the car
> downtown to
> run errands with my wife as a passenger, then came back up that steep
> road to my house again. About 1.5 miles from the house, where the
> steepest part of the hill begins, the car bucked twice, then died. I
> coasted over under a shady tree and waited 5 minutes, then tried
> again.
> The car moved this time. I kept it below 15mph the rest of the way
> home
> and encountered no additional problems. But when I opened the
> hood, the
> Curtis was definitely real hot. So I guess there's yet another fan I
> need to add.
>
> The cells ended up at 45 degrees Celsius again.
>
> The good news is that I've now driven 45 miles without charging the
> car,
> and the resting voltage on the nominal 126V Li-ion pack is still 129V.
>
> Bill Dennis
Bill Dennis
2008-07-13 19:38:24 UTC
Permalink
The Curtis is mounted on a large aluminum plate supplied by CanEV. It's
not finned, though. CanEV used to see them specifically for Geo Metro
conversions. I smeared heat paste on the entire bottom of the 1231C
before mounting it to the plate.

Bill Dennis

Chip Gribben wrote:
> Bill, another fan may not be enough. It sounds like you need to
> dissipate the heat off the controller.
>
> If you mount the controller on an aluminum plate with some heat sink
> grease that may help.
>
> I've seen finned heat sinks for Curtis controllers from KTA several
> years ago. Not sure if they are available anymore or not. But a piece
> of aluminum and if possible mounting the controller in the airflow
> together should help. Although sometimes you are stuck with where the
> controller is so natural airflow is not always available.
>
> The fans should help but dissipating the heat with a heatsink will
> also help even more.
>
> To take it one step further, which will involve alot more work is
> building a heatsink with a built in radiator to run some coolant
> through it. I haven't gone to that extreme yet but have seen people
> do that.
>
> Chip
>
>
>
>
> On Jul 13, 2008, at 3:00 PM, ev-request-UWgVIey+***@public.gmane.org wrote:
>
>
>> Message: 13
>> Date: Sun, 13 Jul 2008 12:14:46 -0600
>> From: Bill Dennis <wjdennis-r9/***@public.gmane.org>
>> Subject: [EVDL] Overheated 1231C
>> To: Electric Vehicle Discussion List <ev-UWgVIey+***@public.gmane.org>
>> Message-ID: <487A4616.6000301-r9/***@public.gmane.org>
>> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>>
>> I think I overheated the Curtis 1231C today. I took the car
>> downtown to
>> run errands with my wife as a passenger, then came back up that steep
>> road to my house again. About 1.5 miles from the house, where the
>> steepest part of the hill begins, the car bucked twice, then died. I
>> coasted over under a shady tree and waited 5 minutes, then tried
>> again.
>> The car moved this time. I kept it below 15mph the rest of the way
>> home
>> and encountered no additional problems. But when I opened the
>> hood, the
>> Curtis was definitely real hot. So I guess there's yet another fan I
>> need to add.
>>
>> The cells ended up at 45 degrees Celsius again.
>>
>> The good news is that I've now driven 45 miles without charging the
>> car,
>> and the resting voltage on the nominal 126V Li-ion pack is still 129V.
>>
>> Bill Dennis
>>
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
>
>
l***@public.gmane.org
2008-07-13 21:27:01 UTC
Permalink
hi wander why those companys selling controllers dont make so dont
overheat blow up etc ?? they charge enough money for them ..lonnie


Bill Dennis
> The Curtis is mounted on a large aluminum plate supplied by CanEV. It's
> not finned, though. CanEV used to see them specifically for Geo Metro
> conversions. I smeared heat paste on the entire bottom of the 1231C
> before mounting it to the plate.
>
> Bill Dennis
>
> Chip Gribben wrote:
>> Bill, another fan may not be enough. It sounds like you need to
>> dissipate the heat off the controller.
>>
>> If you mount the controller on an aluminum plate with some heat sink
>> grease that may help.
>>
>> I've seen finned heat sinks for Curtis controllers from KTA several
>> years ago. Not sure if they are available anymore or not. But a piece
>> of aluminum and if possible mounting the controller in the airflow
>> together should help. Although sometimes you are stuck with where the
>> controller is so natural airflow is not always available.
>>
>> The fans should help but dissipating the heat with a heatsink will
>> also help even more.
>>
>> To take it one step further, which will involve alot more work is
>> building a heatsink with a built in radiator to run some coolant
>> through it. I haven't gone to that extreme yet but have seen people
>> do that.
>>
>> Chip
>>
>>
>>
>>
>> On Jul 13, 2008, at 3:00 PM, ev-request-UWgVIey+***@public.gmane.org wrote:
>>
>>
>>> Message: 13
>>> Date: Sun, 13 Jul 2008 12:14:46 -0600
>>> From: Bill Dennis <wjdennis-r9/***@public.gmane.org>
>>> Subject: [EVDL] Overheated 1231C
>>> To: Electric Vehicle Discussion List <ev-UWgVIey+***@public.gmane.org>
>>> Message-ID: <487A4616.6000301-r9/***@public.gmane.org>
>>> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>>>
>>> I think I overheated the Curtis 1231C today. I took the car
>>> downtown to
>>> run errands with my wife as a passenger, then came back up that steep
>>> road to my house again. About 1.5 miles from the house, where the
>>> steepest part of the hill begins, the car bucked twice, then died. I
>>> coasted over under a shady tree and waited 5 minutes, then tried
>>> again.
>>> The car moved this time. I kept it below 15mph the rest of the way
>>> home
>>> and encountered no additional problems. But when I opened the
>>> hood, the
>>> Curtis was definitely real hot. So I guess there's yet another fan I
>>> need to add.
>>>
>>> The cells ended up at 45 degrees Celsius again.
>>>
>>> The good news is that I've now driven 45 miles without charging the
>>> car,
>>> and the resting voltage on the nominal 126V Li-ion pack is still 129V.
>>>
>>> Bill Dennis
>>>
>>
>>
>> _______________________________________________
>> For general EVDL support, see http://evdl.org/help/
>> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>>
>>
>>
>>
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
Norm Woodward
2008-07-13 23:06:03 UTC
Permalink
This guy:

http://tinyurl.com/65tt58

will cut these 8.5" x 1" finned heat sinks to any size you want. 12.25"
fits a Curtis 1231C perfectly. Use a little heat sink compound and you
have a pretty good heat sink. I have them on my 1231C and on my other
vehicle with a 1221C.

..
Norm
http://www.wacparts.com


Chip Gribben wrote:
> Bill, another fan may not be enough. It sounds like you need to
> dissipate the heat off the controller.
>
> If you mount the controller on an aluminum plate with some heat sink
> grease that may help.
>
> I've seen finned heat sinks for Curtis controllers from KTA several
> years ago. Not sure if they are available anymore or not. But a piece
> of aluminum and if possible mounting the controller in the airflow
> together should help. Although sometimes you are stuck with where the
> controller is so natural airflow is not always available.
>
> The fans should help but dissipating the heat with a heatsink will
> also help even more.
>
> To take it one step further, which will involve alot more work is
> building a heatsink with a built in radiator to run some coolant
> through it. I haven't gone to that extreme yet but have seen people
> do that.
>
> Chip
>
>
>
>
> On Jul 13, 2008, at 3:00 PM, ev-request-UWgVIey+***@public.gmane.org wrote:
>
>> Message: 13
>> Date: Sun, 13 Jul 2008 12:14:46 -0600
>> From: Bill Dennis <wjdennis-r9/***@public.gmane.org>
>> Subject: [EVDL] Overheated 1231C
>> To: Electric Vehicle Discussion List <ev-UWgVIey+***@public.gmane.org>
>> Message-ID: <487A4616.6000301-r9/***@public.gmane.org>
>> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>>
>> I think I overheated the Curtis 1231C today. I took the car
>> downtown to
>> run errands with my wife as a passenger, then came back up that steep
>> road to my house again. About 1.5 miles from the house, where the
>> steepest part of the hill begins, the car bucked twice, then died. I
>> coasted over under a shady tree and waited 5 minutes, then tried
>> again.
>> The car moved this time. I kept it below 15mph the rest of the way
>> home
>> and encountered no additional problems. But when I opened the
>> hood, the
>> Curtis was definitely real hot. So I guess there's yet another fan I
>> need to add.
>>
>> The cells ended up at 45 degrees Celsius again.
>>
>> The good news is that I've now driven 45 miles without charging the
>> car,
>> and the resting voltage on the nominal 126V Li-ion pack is still 129V.
>>
>> Bill Dennis
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
Jeff Shanab
2008-07-13 22:41:56 UTC
Permalink
> I have a basic question, When all of your batteries are connected, I
> understand a single charger sends power to the pack as a whole,
> regardless of the intividual batteries voltage or DoD. How do people
> monitor individual batteries, while they are still in the pack?

What kind of batteries are you talking about? All batteries need this
equalization, but they type determines the sophistication level needed.
There are 3 ways of balancing,
Overcharge
Bypass
Charge Shuttling

It can be done only at end of charge or continously. (even totally
discharge in nicad case)

The least expensive method is for flooded lead. Just overcharge and the
ones that are full will have lost more water, make it up in water at the
end of the week or month. Note a BMS could reduce your water usage. Most
golf carts and forklifts work this way.

If you try this with AGM's(Absorbed glass mat, or otherwise sealed
lead-acid) you will destroy them.
The orbitals I have have a platinum pellet inside and some pressure
vents. The platinum is the catalyst needed to re-combine the gas back
into water.
Once the cell is full, we must keep the charge voltage at 14.77 and
never go over 1.5A at that point. If we do the pressure will build up
and gas can escape the vents. The batery will have lost water and it
looses capacity from that point on.
So I use rudman regulators which bypass current when the voltage
hits 14.77 and talk back to the charger through an isolated phone-line
and tell it to "back off" the amps.
I am gonna switch to the Lee Hart Battery balancer becuase I have
had regulators die and I'd like the feedback and charge shuttleing of
Lee's system.
Gells are equally sensitive.
Look through the archives for "zener regulators" for a cheap but manual
way of balancing.

If we are talking flooded Nicad, they can be overcharged like flooded
lead acid, but charge eff is lower.
If we are talking about Nimh, Paralleling is a big, big problem (voltage
will drop when full, temperature rises) If you miss that point you will
go into thermal runnaway and melt them down. Besides, finding cells
large enough not to parallel is illeagal anyway. (Don't know BMS
requirements for cells in series. Maybe seperate parallel strings
charged with individual control is doable for nicad

If you are talking LiFePo4 or lipoly. the requirements are a lot more
strict. Every cell in series must be protected (jury still out on if we
can parallel them ok) Most companies makeing bms's want to sell you
cells, No one can really give calender life data yet, except for the
lithium cobalt cells and they are flammible (understatement, they
generate their own oxygen during breakdown) The voltage must be limited
to a different voltage for each variation of the chemistry, the accuracy
of these measurements needs to be better and the flat voltage discharge
almost mandates some form of columb counting to get good idea of
SOC.(State Of Charge)

>
> In one example I was told a BMS was needed for each 4 cells. Again how
> does it isolate it self from batteries down the line?
every 4 cells?, kinda sounds like suggestions for Lithium ion. THere
are a few independent BMS's out there,
The rudmen regs are one per 12V battery (6 cells) but can be made for 6V
(3 cells)
The Lee Hart Balancer is set for one dc-dc for the voltage of your
modue, say 12V and a relay to connect it one at a time to the batteries
for each module.
His relay boards are for 8 modules.

I have 24 modules.24 MK2D regs are 40*24 = $960, if I wanted the ones
with data collection(feedback) they are 125+23*75 =$1850
For small numbers of modules, the redman regs are economical and work
right out of the box with the charger
For large numbers of modules and something with memory and health
monitoring, the Lee hart balancer is cheaper but requires some work.
(soldering and programming)

>
> And finally, those who use several smaller chargers, do they need to
> disconect bthat set of batteries from the rest?
This technique is sworn by for some people, usually ones with small
numbers of modules. (Using modules to indicate battery here either 12V
or 6V,)
But is generally frowned upon for one reason. A single charger can fail
leeving you with a seriously imbalanced pack. The first time you fail to
notice it you destroy a battery. As the quantity of modules increases,
the chances of one of them being bad at any given time increases.
Admittidly, I found the same problem with MK2 regs, one failed on me and
stuck on draining the battery. I didn't see it, reversed a cell and
vented the battery. (boy does that stink). I didn't know what happened
until later when it happened again. This time I caught it before I
applied a load.

Something like the paktracker would help notify me of this or even the
simple 2 led 1/2 pack monitor.

My current thinking is to try charge shuttleing instead of bypass. You
need a dc-dc for the aux battery anyway, and using relays to connect
this dc-dc to each module one at a time is like having a charger for
each. Because the same meter is used to measure each module and the unit
is controlled by a micro, The calibration should remain pretty good.
Because it charge shuttles, one weak battery can be helped by the
others. I should get the average of the whole pack instead of the range
of the weakest battery. My hope is that I will be notified by my
software of that weakest battery and that I will have more time to do
something about it since it's depth of discharge each trip will be
less. Balancing only at full means the poor weakest battery gets worked
harder each drive than the rest amplifying the aging effect. Balancing
continuously lessens the work load on the weakest battery so it should
actually help them age together. Like the rotate tire delima on a front
wheel drive. Do I want all my tires to wear out at the same time or 2 at
a time?
>
> Also, when doing an equilization charge, are individual, lower voltage
> batteries removed and charged up to the standard, then replaced?
An isolated charger can be connected directly to the battery without
disconnecting it from the string. This is a requirement of many small
chargers or the shared charger systems.
>
> Thanks
>
> marc

The most important piece of equipment is the emeter or evision. It tells
you how many watt-hours you put in and take out.
ref
Manzanita micro Chargers and regulators
http://www.manzanitamicro.com/
Lee Harts battery balancer Charge Shullteing balancer
http://www.geocities.com/sorefeets/balancerland/
MetricMind Lithium ion regs
http://www.metricmind.com/
EVstuff
2008-07-13 23:21:24 UTC
Permalink
I have a question: ??
I'm not sure if this is for Jeff or Mark.
That information got lost in the "threading"

What's up with legality of large Nimh ??
Thanks.
Tom Meyers



----- Original Message -----
From: "Jeff Shanab" <jshanab-***@public.gmane.org>
To: <ev-UWgVIey+***@public.gmane.org>
Sent: Sunday, July 13, 2008 6:41 PM
Subject: [EVDL] BMS, Charging and monitoring batteries

)SNIP(

> If we are talking about Nimh, Paralleling is a big, big problem (voltage
> will drop when full, temperature rises) If you miss that point you will
> go into thermal runnaway and melt them down. Besides, finding cells
> large enough not to parallel is illeagal anyway.
)SNIP(
Jeff Shanab
2008-07-14 02:19:50 UTC
Permalink
I have a zilla so this may not apply but I have had some cooling issues
when the temp went over 112.

If it heats up slowly, it will throttle back to where I can't pull
more than 50A from the batteries, Not sure what motor amps but it is
almost useless.
If it heats up quicky, it will cut out and back in before I can take
my foot off the pedal, chirping the tires and hurting my neck.
This was determined to be loosing prime on the pump when
accelerating from the 6th stoplight in a row. The @#$% tank I used was
one of those 5-1/4 computer bay poly tanks, it is just to small and
horizontal. (I folded up a 5" cube tank out of brass this weekend,
taking it to the radiator shop to be soldered up tomorrow)
Once it heated up without bucking, I got going a little faster, but
just shut off. I think this is overtemp for a period of time. ( I should
check the stored codes.)
Jeff Shanab
2008-07-14 02:27:39 UTC
Permalink
Wikipedia says it pretty good
http://en.wikipedia.org/wiki/Nickel_metal_hydride
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