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Discussion Starter #1
My chassis is somehow connected to my pack negative. There is 150v from pack
positive to the chassis. There is enough amperage to make a 6 watrt 120v
night light filament glow red. I measure 14v across the bulb (VM in parallel
with the bulb.) I blew out the brush area of the motor. There was little
there.

My pack negative and negative lead to the motor are bolted together at the
controller tang. In order to isolate the problem, I disconnected them. I
then measured 157.5v from the pack positive to the negative side of the
pack. 30.0v to the neg motor lead, 29.4 to the chasis and 30 to the
controller negative. When I connected the negative lead to the controller
(motor not connected) I measured 152v between positive and chassis. When I
disconnected the controller and connected the negative lead to the motor, I
again measured 153v between pack positive and chassis.

Then, in frustration, I measured 108v between the pack positive and the
electrical ground on an extension cord! Nothing on the car was connected to
the building electrical system!

Anybody out there with any ideas where the problem lies? Or what else I
should check?

Thanks,
storm

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http://www.austinev.org/evalbum/1059
http://stormselectric.blogspot.com/
Storm
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70 Posts
Discussion Starter #2
Hello Storm,

Disconnect the battery pack from the controller and from the battery
charger. Connect up your test light or volt meter from the battery most
positive and to the chassis.

Now spray the entire top of the batteries with Windex that has ammonia in
it. The ammonia is a very good battery neutralizer. Spray the batteries,
the battery boxes or battery rack and surrounding metal structure and wipe
down with paper towels and monitor the voltage indications.

I do this cleaning about every three or four months after I water and do a
equalization charge.

This is a normal conductance voltage leakage from the batteries to the
chassis even it's a non conductor material.

I have a 180 volt pack, and when its super clean, the voltage will still be
about 0.1 volt. After charging these batteries for about 3 months, the
voltage will normally climb to about 60 volts. One time I have something
like 170 volts.

Try doing this cleaning test and see what's happen.

Roland


----- Original Message -----
From: "storm connors" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Sunday, August 26, 2007 6:32 PM
Subject: [EVDL] Finding a ground leak


> My chassis is somehow connected to my pack negative. There is 150v from
> pack
> positive to the chassis. There is enough amperage to make a 6 watrt 120v
> night light filament glow red. I measure 14v across the bulb (VM in
> parallel
> with the bulb.) I blew out the brush area of the motor. There was little
> there.
>
> My pack negative and negative lead to the motor are bolted together at the
> controller tang. In order to isolate the problem, I disconnected them. I
> then measured 157.5v from the pack positive to the negative side of the
> pack. 30.0v to the neg motor lead, 29.4 to the chasis and 30 to the
> controller negative. When I connected the negative lead to the controller
> (motor not connected) I measured 152v between positive and chassis. When I
> disconnected the controller and connected the negative lead to the motor,
> I
> again measured 153v between pack positive and chassis.
>
> Then, in frustration, I measured 108v between the pack positive and the
> electrical ground on an extension cord! Nothing on the car was connected
> to
> the building electrical system!
>
> Anybody out there with any ideas where the problem lies? Or what else I
> should check?
>
> Thanks,
> storm
>
> --
> http://www.austinev.org/evalbum/1059
> http://stormselectric.blogspot.com/
> Storm
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>

_______________________________________________
For subscription options, see
http://lists.sjsu.edu/mailman/listinfo/ev
 
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