# [EVDL] Ground fault troubleshooting



## EVDL List (Jul 27, 2007)

Barry,

I'd focus first on the batteries that are not in the insulated box. I had a
similar problem with my Russco charger - little bits of acid mist were
spilling onto the metal racks and creating a connection to ground. It
doesn't take much to create a connection and it only takes a few mA to trip
those breakers. Painted racks won't make much difference. Make sure you
clean off those racks and any tie-down bars and try running your charger
again.

On the advice of Lee Hart, I created "bathtubs" of heavy plastic sheeting to
cover the bottom and up the sides of the batteries. I also wrapped the
battery tie-down bars in triple layers of electrical tape. That combination
of things now prevents any acid mist from getting on the battery racks and
I've had no more GFCI issues.

- Peter Flipsen Jr
http://www.evalbum.com/1974




On Fri, Sep 4, 2009 at 11:59 AM, Barry Oppenheim <[email protected]


> > wrote:
> 
> > I am having a problem with a ground fault for my main traction pack and am
> > looking for some guidance. When turning on the charger the GFCI
> ...


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## EVDL List (Jul 27, 2007)

I had a bad wire on my input wire. It also tripped my GFI plug in the Garage. I disconnected the ground wire to the charger & it works. Not a good solution but you might check your wiring to the charger. Use a different cord to the charger for instance to test. Lawrence Rhodes..


From: "Barry Oppenheim" <[email protected]>
Subject: [EVDL] Ground fault troubleshooting
To: "Electric Vehicle Discussion List" <[email protected]>
Message-ID: <[email protected]>
Content-Type: text/plain; charset="us-ascii"

I am having a problem with a ground fault for my main traction pack and am
looking for some guidance. When turning on the charger the GFCI immediately
trips.

Quick background info:
144V pack (17 x 6V in insulated/isolated box, 7 on painted angle iron racks
under hood)
PFC20 (plugged into 20A/110V GFCI)
Zilla 1K
Warp 9

I measured the battery voltage to the chassis for each battery. The most
positive end of the pack is ~-2V and the most negative end is ~144V.
Current across a 10K resistor is about .5mA at the most positive end
gradually increasing to 9mA at the most negative end.

I've cleaned all of the batteries with Windex. There is no obvious leakage
from any of the batteries. I tried a second GFCI outlet on a different
circuit with the same result. The EV otherwise is running perfectly.

As an aside when I check the current on the higher current leakage batteries
the "Main Contactor Off" light on my Hairball lights up.

Any help in tracking down the source of this would be appreciated.

Barry Oppenheim
New Hope, PA
www.JustAnotherEVConversion.blogspot.com

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## EVDL List (Jul 27, 2007)

My biggest GFI problems were with the (powder coated) metal hold down bits 
that went around the battery tops. Even parts that were 1" from a terminal 
would collect acid, corrode the underside of the hold downs, and cause GFI 
problems. Enclosing batteries in a PP or ABS box fixed that.

Anyone know a good NON-CONDUCTIVE material to use for hold downs?

I believe Roland mentioned motor brush dust could cause GFI issues.

My isolation check is to use the resistance function on my DMM. Terminals 
go between a traction pack terminal and the 12V SLI battery terminal. 
Unless it reads OL, something's not clean enough!

-Adrian



> SLPinfo.org wrote:
> 
> > Barry,
> >
> ...


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## EVDL List (Jul 27, 2007)

Try that Plasti Dip by Performix or similar . I got some from Home Depot in 
red and black for coating my new battery terminals. You can thin it with 
naphtha. The specs said its acid proof and can use it on battery fittings 
and trays.

Roland


----- Original Message ----- 
From: "Adrian DeLeon" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Friday, September 04, 2009 5:37 PM
Subject: Re: [EVDL] Ground fault troubleshooting


> My biggest GFI problems were with the (powder coated) metal hold down bits
> that went around the battery tops. Even parts that were 1" from a terminal
> would collect acid, corrode the underside of the hold downs, and cause GFI
> problems. Enclosing batteries in a PP or ABS box fixed that.
>
> Anyone know a good NON-CONDUCTIVE material to use for hold downs?
>
> I believe Roland mentioned motor brush dust could cause GFI issues.
>
> My isolation check is to use the resistance function on my DMM. Terminals
> go between a traction pack terminal and the 12V SLI battery terminal.
> Unless it reads OL, something's not clean enough!
>
> -Adrian
>
>


> SLPinfo.org wrote:
> >
> > > Barry,
> > >
> ...


----------



## EVDL List (Jul 27, 2007)

How about:

http://www.mcmaster.com/#fiberglass-angles/=3hxpzo

SteveS

Adrian DeLeon wrote:
> My biggest GFI problems were with the (powder coated) metal hold down bits 
> that went around the battery tops. Even parts that were 1" from a terminal 
> would collect acid, corrode the underside of the hold downs, and cause GFI 
> problems. Enclosing batteries in a PP or ABS box fixed that.
>
> Anyone know a good NON-CONDUCTIVE material to use for hold downs?
>
> I believe Roland mentioned motor brush dust could cause GFI issues.
>
> My isolation check is to use the resistance function on my DMM. Terminals 
> go between a traction pack terminal and the 12V SLI battery terminal. 
> Unless it reads OL, something's not clean enough!
>
> -Adrian
>
>


> SLPinfo.org wrote:
> >
> >
> >> Barry,
> ...


----------



## EVDL List (Jul 27, 2007)

> My biggest GFI problems were with the (powder coated) metal hold down
> bits that went around the battery tops. Even parts that were 1" from a
> terminal would collect acid, corrode the underside of the hold downs,
> and cause GFI problems. Enclosing batteries in a PP or ABS box fixed
> that.
>
> Anyone know a good NON-CONDUCTIVE material to use for hold downs?
>
> I believe Roland mentioned motor brush dust could cause GFI issues.
>
> My isolation check is to use the resistance function on my DMM.
> Terminals go between a traction pack terminal and the 12V SLI battery
> terminal. Unless it reads OL, something's not clean enough!
>
> -Adrian
>
>


> SLPinfo.org wrote:
> >
> > Barry,
> >
> ...


----------



## EVDL List (Jul 27, 2007)

Adrian DeLeon wrote:
> My biggest GFI problems were with the (powder coated) metal hold down bits 
> that went around the battery tops. Even parts that were 1" from a terminal 
> would collect acid, corrode the underside of the hold downs, and cause GFI 
> problems. Enclosing batteries in a PP or ABS box fixed that.
> 
> Anyone know a good NON-CONDUCTIVE material to use for hold downs?

I'm using 1 inch wide polyester webbing with steel cam buckles. When I learned that the polyester webbing is rated for 3500 pounds breaking strength (higher than the steel buckle), it seemed like a good choice! Time will tell.
I got my straps from strapworks.com:
http://www.strapworks.com/Metal_Cam_Straps_p/cs1p.htm

Thanks,
Josh


> 
> I believe Roland mentioned motor brush dust could cause GFI issues.
> 
> My isolation check is to use the resistance function on my DMM. Terminals 
> go between a traction pack terminal and the 12V SLI battery terminal. 
> Unless it reads OL, something's not clean enough!
> 
> -Adrian
> 
>


> SLPinfo.org wrote:
> >
> >> Barry,
> >>
> ...


----------



## EVDL List (Jul 27, 2007)

Thanks for all the suggestions. Still having the same problem. Here is what
I've done since the last email.

1. Recleaned all of the battery tops with Windex
2. Put plastic sheeting (vinyl shower curtain liners) between the metal
battery racks and batteries.
3. Checked for shorts in the cord leading from outlet to charger.
4. Removed all battery hold downs.

The most positive battery on the pack reads +2V/.7mA to chassis ground. The
next battery reads -4V/.7mA to chassis ground. Each battery potential to
the chassis increases by 6V and a few tenths of a mA until the most negative
battery. That reads -144V/9mA.

Based on the above the lowest resistance is at the most positive end of the
pack and the highest at the most negative.

Shouldn't this indicate that the most positive battery is causing the fault?

Does the crossover point from positive voltage to negative voltage indicate
the location of the fault?

Barry Oppenheim
Wrightstown, PA
www.JustAnotherEVConversion.blogspot.com

-----Original Message-----
From: [email protected] [mailto:[email protected]]On
Behalf Of Barry Oppenheim
Sent: Friday, September 04, 2009 1:59 PM
To: Electric Vehicle Discussion List
Subject: [EVDL] Ground fault troubleshooting


I am having a problem with a ground fault for my main traction pack and am
looking for some guidance. When turning on the charger the GFCI immediately
trips.

Quick background info:
144V pack (17 x 6V in insulated/isolated box, 7 on painted angle iron racks
under hood)
PFC20 (plugged into 20A/110V GFCI)
Zilla 1K
Warp 9

I measured the battery voltage to the chassis for each battery. The most
positive end of the pack is ~-2V and the most negative end is ~144V.
Current across a 10K resistor is about .5mA at the most positive end
gradually increasing to 9mA at the most negative end.

I've cleaned all of the batteries with Windex. There is no obvious leakage
from any of the batteries. I tried a second GFCI outlet on a different
circuit with the same result. The EV otherwise is running perfectly.

As an aside when I check the current on the higher current leakage batteries
the "Main Contactor Off" light on my Hairball lights up.

Any help in tracking down the source of this would be appreciated.

Barry Oppenheim
New Hope, PA
www.JustAnotherEVConversion.blogspot.com

_______________________________________________
General EVDL support: http://evdl.org/help/
Usage guidelines: http://evdl.org/help/index.html#conv
Archives: http://evdl.org/archive/
Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev


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_______________________________________________
General EVDL support: http://evdl.org/help/
Usage guidelines: http://evdl.org/help/index.html#conv
Archives: http://evdl.org/archive/
Subscription options: http://lists.sjsu.edu/mailman/listinfo/ev


----------



## EVDL List (Jul 27, 2007)

> Barry Oppenheim wrote:
> > Thanks for all the suggestions. Still having the same problem...
> > 1. Recleaned all of the battery tops with Windex
> > 2. Put plastic sheeting (vinyl shower curtain liners) between the metal
> ...


----------



## EVDL List (Jul 27, 2007)

Lee,

Thanks for the help. I will give it a try.

I've been trying the same thing by measuring DC current from the battery
pack to chassis with a 10K resistor in series. Does this serve the same
function as measuring from the AC mains?

I'm starting the DC divide and conquer method by unplugging the battery pack
from the fuse box that holds all the accessory fuses and contactors. I
found that either the negative or positive end of the pack has only 25 micro
amps to the chassis across a 10K resistor. And this is directly from the
Evision half battery pack tap since when I pull the fuse protecting that
circuit the current goes to zero.

When I measure the resistance between the chassis and the isolated fuse box
positive or negative I get 5-7 megaohms indicating some continuity. Is 5-7
megaohms acceptable or should this be zero?

Thanks again,
Barry



-----Original Message-----
From: [email protected] [mailto:[email protected]]On
Behalf Of Lee Hart
Sent: Sunday, September 06, 2009 4:11 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Ground fault troubleshooting




> Barry Oppenheim wrote:
> > Thanks for all the suggestions. Still having the same problem...
> > 1. Recleaned all of the battery tops with Windex
> > 2. Put plastic sheeting (vinyl shower curtain liners) between the metal
> ...


----------



## EVDL List (Jul 27, 2007)

Update on the ground fault. I used Lee's method outlined below (except a
10K resistor since I had those lying around). The battery pack has
absolutely no current leakage  The wires to the fuse box are another
story.

Initially pretty much everything in the fuse box was faulting. After
disconnecting fuses and lugs the fault isolated to the positive and negative
legs leading out of the fuse box to the controller.

The controller lugs and controller are clean. I haven't disconnected the
controller lugs but I did look at the motor. Definitely a lot of grime on
it. The cable going from A2 to S2 has light rust on the terminals.

It looks like the motor may be the culprit. So the next question is what is
the easiest way to clean the motor without removing it?

Barry


-----Original Message-----
From: [email protected] [mailto:[email protected]]On
Behalf Of Lee Hart
Sent: Sunday, September 06, 2009 4:11 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Ground fault troubleshooting




> Barry Oppenheim wrote:
> > Thanks for all the suggestions. Still having the same problem...
> > 1. Recleaned all of the battery tops with Windex
> > 2. Put plastic sheeting (vinyl shower curtain liners) between the metal
> ...


----------

