subject:"Re\: \[EVDL\] Ground Faults"

Re: [EVDL] Ground Faults

2016-06-01 Thread dovepa via EV

Could you be a little more detailed? You disconnected everything from what? 
Each other? The battery pack? Etc?   If you have a series wound DC motor then 
carbon build up from the brushes can create a path.


Sent from my Verizon, Samsung Galaxy smartphone
 Original message From: John Lussmyer via EV 
 Date: 6/1/16  7:35 PM  (GMT-06:00) To: Electric Vehicle 
Discussion List  Subject: [EVDL] Ground Faults 
Well, I've discovered that my truck has a ground fault of some kind in it 
somewhere.
For a long time, I've been charging off the Welder outlet in my shop.  I 
recently installed a nice big 240v 60A GFCI breaker for a charging outlet at 
the house.
The GFCI trips every time I try to charge.  It doesn't trip if I plug a welder 
into the outlet.

Poking around the pack with a voltmeter, I get some solid voltage readings to 
the frame of the truck.
So, I started disconnecting things.  Disconnected everything except the charger 
(kinda need that!).
Still trips the GFCI.
Still getting weak voltage readings from various points in the pack.  (Not 
always consistent, not always constant.)

Running out of ideas...

--
Worlds only All Electric F-250 truck! 
http://john.casadelgato.com/Electric-Vehicles/1995-Ford-F-250
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Re: [EVDL] Ground Faults

2016-06-01 Thread John Lussmyer via EV

I mean EVERYTYHING other than the charger.
There are contactors on both sides of the pack, so the controller and motor are 
fully disconnected.
I also disconnected the volt/amp meter, and BMS (12v power) as well.
Also disconnected the "battery +" wire to the zilla hairball.
Unhooked the DC-DC.

I'm wondering if I'm getting dirt/damp leakage from the pack to the frame.

On Wed Jun 01 18:08:15 PDT 2016 ev@lists.evdl.org said:
>Could you be a little more detailed? You disconnected everything from what? 
>Each other? The battery pack? Etc?   If you have a series wound DC motor then 
>carbon build up from the brushes can create a path.
>
>Sent from my Verizon, Samsung Galaxy smartphone
> Original message From: John Lussmyer via EV 
> Date: 6/1/16  7:35 PM  (GMT-06:00) To: Electric Vehicle 
>Discussion List  Subject: [EVDL] Ground Faults
>Well, I've discovered that my truck has a ground fault of some kind in it 
>somewhere.
>For a long time, I've been charging off the Welder outlet in my shop.  I 
>recently installed a nice big 240v 60A GFCI breaker for a charging outlet at 
>the house.
>The GFCI trips every time I try to charge.  It doesn't trip if I plug a welder 
>into the outlet.
>
>Poking around the pack with a voltmeter, I get some solid voltage readings to 
>the frame of the truck.
>So, I started disconnecting things.  Disconnected everything except the 
>charger (kinda need that!).
>Still trips the GFCI.
>Still getting weak voltage readings from various points in the pack.  (Not 
>always consistent, not always constant.)
>
>Running out of ideas...
>
>--
>Worlds only All Electric F-250 truck! 
>http://john.casadelgato.com/Electric-Vehicles/1995-Ford-F-250
>___
>UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
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http://john.casadelgato.com/Electric-Vehicles/1995-Ford-F-250

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Re: [EVDL] Ground Faults

2016-06-01 Thread Rick Beebe via EV

When I had a lead pack in my truck I had rampant leakage from the pack 
to the frame. I think the acid mist and dirt are conductive. I kept 
trying to find the culprit battery by segmenting the pack and the leak 
would literally just move around.


And I had the same problem as you--it was tripping the GFCI outlet. I 
had to take out the GFCI outlet and install a regular one. (The truck 
had a 110v Russco charger in it).


I don't think LiFePo4 cells are as susceptible although I have heard 
several stories of different makes having conductive cases. When I put 
lithium in the truck put all the cells in insulated boxes. If I have a 
ground fault now it will most likely be carbon buildup in the motor.


--Rick

On 6/1/2016 11:48 PM, John Lussmyer via EV wrote:

I mean EVERYTYHING other than the charger.
There are contactors on both sides of the pack, so the controller and motor are 
fully disconnected.
I also disconnected the volt/amp meter, and BMS (12v power) as well.
Also disconnected the "battery +" wire to the zilla hairball.
Unhooked the DC-DC.

I'm wondering if I'm getting dirt/damp leakage from the pack to the frame.

On Wed Jun 01 18:08:15 PDT 2016 ev@lists.evdl.org said:

Could you be a little more detailed? You disconnected everything from what? 
Each other? The battery pack? Etc?   If you have a series wound DC motor then 
carbon build up from the brushes can create a path.

Sent from my Verizon, Samsung Galaxy smartphone
 Original message From: John Lussmyer via EV  
Date: 6/1/16  7:35 PM  (GMT-06:00) To: Electric Vehicle Discussion List 
 Subject: [EVDL] Ground Faults
Well, I've discovered that my truck has a ground fault of some kind in it 
somewhere.
For a long time, I've been charging off the Welder outlet in my shop.  I 
recently installed a nice big 240v 60A GFCI breaker for a charging outlet at 
the house.
The GFCI trips every time I try to charge.  It doesn't trip if I plug a welder 
into the outlet.

Poking around the pack with a voltmeter, I get some solid voltage readings to 
the frame of the truck.
So, I started disconnecting things.  Disconnected everything except the charger 
(kinda need that!).
Still trips the GFCI.
Still getting weak voltage readings from various points in the pack.  (Not 
always consistent, not always constant.)

Running out of ideas...

--
Worlds only All Electric F-250 truck! 
http://john.casadelgato.com/Electric-Vehicles/1995-Ford-F-250
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Re: [EVDL] Ground Faults

2016-06-02 Thread Collin Kidder via EV

Yes, I've had this same trouble with LiFePO4 cells (Thundersky). I
believe that the cases might be ever so slightly conductive. Also, the
car was in a somewhat salty environment by the ocean and sea mist and
dirt caused a build up of conductive material over the top of
everything. So, I cleaned the tops of all of the cells, especially
around the terminals. This helped quite a bit. I still ended up with a
small amount of ground leakage but much better than it was. I don't
know that it can be very easily fixed for good with Thundersky cells.
I'd probably have to insulate every single cell from each other and
the case.

On Wed, Jun 1, 2016 at 11:56 PM, Rick Beebe via EV  wrote:
> When I had a lead pack in my truck I had rampant leakage from the pack to
> the frame. I think the acid mist and dirt are conductive. I kept trying to
> find the culprit battery by segmenting the pack and the leak would literally
> just move around.
>
> And I had the same problem as you--it was tripping the GFCI outlet. I had to
> take out the GFCI outlet and install a regular one. (The truck had a 110v
> Russco charger in it).
>
> I don't think LiFePo4 cells are as susceptible although I have heard several
> stories of different makes having conductive cases. When I put lithium in
> the truck put all the cells in insulated boxes. If I have a ground fault now
> it will most likely be carbon buildup in the motor.
>
> --Rick
>
>
> On 6/1/2016 11:48 PM, John Lussmyer via EV wrote:
>>
>> I mean EVERYTYHING other than the charger.
>> There are contactors on both sides of the pack, so the controller and
>> motor are fully disconnected.
>> I also disconnected the volt/amp meter, and BMS (12v power) as well.
>> Also disconnected the "battery +" wire to the zilla hairball.
>> Unhooked the DC-DC.
>>
>> I'm wondering if I'm getting dirt/damp leakage from the pack to the frame.
>>
>> On Wed Jun 01 18:08:15 PDT 2016 ev@lists.evdl.org said:
>>>
>>> Could you be a little more detailed? You disconnected everything from
>>> what? Each other? The battery pack? Etc?   If you have a series wound DC
>>> motor then carbon build up from the brushes can create a path.
>>>
>>> Sent from my Verizon, Samsung Galaxy smartphone
>>>  Original message From: John Lussmyer via EV
>>>  Date: 6/1/16  7:35 PM  (GMT-06:00) To: Electric Vehicle
>>> Discussion List  Subject: [EVDL] Ground Faults
>>> Well, I've discovered that my truck has a ground fault of some kind in it
>>> somewhere.
>>> For a long time, I've been charging off the Welder outlet in my shop.  I
>>> recently installed a nice big 240v 60A GFCI breaker for a charging outlet at
>>> the house.
>>> The GFCI trips every time I try to charge.  It doesn't trip if I plug a
>>> welder into the outlet.
>>>
>>> Poking around the pack with a voltmeter, I get some solid voltage
>>> readings to the frame of the truck.
>>> So, I started disconnecting things.  Disconnected everything except the
>>> charger (kinda need that!).
>>> Still trips the GFCI.
>>> Still getting weak voltage readings from various points in the pack.
>>> (Not always consistent, not always constant.)
>>>
>>> Running out of ideas...
>>>
>>> --
>>> Worlds only All Electric F-250 truck!
>>> http://john.casadelgato.com/Electric-Vehicles/1995-Ford-F-250
>>> ___
>>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
>>> http://lists.evdl.org/listinfo.cgi/ev-evdl.org
>>> Read EVAngel's EV News at http://evdl.org/evln/
>>> Please discuss EV drag racing at NEDRA
>>> (http://groups.yahoo.com/group/NEDRA)
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>>
>>
>> --
>>
>> Worlds only All Electric F-250 truck!
>> http://john.casadelgato.com/Electric-Vehicles/1995-Ford-F-250
>>
>> ___
>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
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>> Read EVAngel's EV News at http://evdl.org/evln/
>> Please discuss EV drag racing at NEDRA
>> (http://groups.yahoo.com/group/NEDRA)
>>
>
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Re: [EVDL] Ground Faults

2016-06-02 Thread Cor van de Water via EV

One solution is to make sure you have a good ground connection and not use 
GFCI. The US standard is ridiculously sensitive at 5 mA while in Europe the 
residential GFCI trigger at 30 mA. I have a lot of standard lab power supplies 
that I cannot plug into the GFCI outlet or it will trigger instantly due to the 
noose suppressing capacitors on the line that conduct spikes to ground to pass 
EMC standards. Apparently there is enough noise on my residential power that 
the GFCI triggers on the current that is going to ground through these caps so 
it is not necessarily a galvanic leakage. It may simply be decoupling caps in 
your power supply (charger) that cause enough leakage. 
It could help if you open the charger and inspect for caps to ground. You can 
modify this to a large value cap between the lines and only a small value to 
ground or even (if there are two caps from each phase to ground) leaving the 2 
caps in series between the lines but cut their connection to ground to remove 
the leakage current. Do make sure in that case that the ground wire is still 
connected to your car frame. 
Success hunting the leakage ghosts!
Cor

> On Jun 2, 2016, at 6:25 AM, Collin Kidder via EV  wrote:
> 
> Yes, I've had this same trouble with LiFePO4 cells (Thundersky). I
> believe that the cases might be ever so slightly conductive. Also, the
> car was in a somewhat salty environment by the ocean and sea mist and
> dirt caused a build up of conductive material over the top of
> everything. So, I cleaned the tops of all of the cells, especially
> around the terminals. This helped quite a bit. I still ended up with a
> small amount of ground leakage but much better than it was. I don't
> know that it can be very easily fixed for good with Thundersky cells.
> I'd probably have to insulate every single cell from each other and
> the case.
> 
>> On Wed, Jun 1, 2016 at 11:56 PM, Rick Beebe via EV  wrote:
>> When I had a lead pack in my truck I had rampant leakage from the pack to
>> the frame. I think the acid mist and dirt are conductive. I kept trying to
>> find the culprit battery by segmenting the pack and the leak would literally
>> just move around.
>> 
>> And I had the same problem as you--it was tripping the GFCI outlet. I had to
>> take out the GFCI outlet and install a regular one. (The truck had a 110v
>> Russco charger in it).
>> 
>> I don't think LiFePo4 cells are as susceptible although I have heard several
>> stories of different makes having conductive cases. When I put lithium in
>> the truck put all the cells in insulated boxes. If I have a ground fault now
>> it will most likely be carbon buildup in the motor.
>> 
>> --Rick
>> 
>> 
>>> On 6/1/2016 11:48 PM, John Lussmyer via EV wrote:
>>> 
>>> I mean EVERYTYHING other than the charger.
>>> There are contactors on both sides of the pack, so the controller and
>>> motor are fully disconnected.
>>> I also disconnected the volt/amp meter, and BMS (12v power) as well.
>>> Also disconnected the "battery +" wire to the zilla hairball.
>>> Unhooked the DC-DC.
>>> 
>>> I'm wondering if I'm getting dirt/damp leakage from the pack to the frame.
>>> 
>>> On Wed Jun 01 18:08:15 PDT 2016 ev@lists.evdl.org said:

 Could you be a little more detailed? You disconnected everything from
 what? Each other? The battery pack? Etc?   If you have a series wound DC
 motor then carbon build up from the brushes can create a path.

 Sent from my Verizon, Samsung Galaxy smartphone
  Original message From: John Lussmyer via EV
  Date: 6/1/16  7:35 PM  (GMT-06:00) To: Electric Vehicle
 Discussion List  Subject: [EVDL] Ground Faults
 Well, I've discovered that my truck has a ground fault of some kind in it
 somewhere.
 For a long time, I've been charging off the Welder outlet in my shop.  I
 recently installed a nice big 240v 60A GFCI breaker for a charging outlet 
 at
 the house.
 The GFCI trips every time I try to charge.  It doesn't trip if I plug a
 welder into the outlet.

 Poking around the pack with a voltmeter, I get some solid voltage
 readings to the frame of the truck.
 So, I started disconnecting things.  Disconnected everything except the
 charger (kinda need that!).
 Still trips the GFCI.
 Still getting weak voltage readings from various points in the pack.
 (Not always consistent, not always constant.)

 Running out of ideas...

 --
 Worlds only All Electric F-250 truck!
 http://john.casadelgato.com/Electric-Vehicles/1995-Ford-F-250
 ___
 UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
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Re: [EVDL] Ground Faults

2016-06-02 Thread Russ Sciville via EV

I have also noticed this on my CALB powered EV.
It was traced to just one cell by measuring the voltage between the chassis and 
the cells.The leaking volts swung negative on one side and positive on the 
other and when the reading was zero, I had found the faulty one. It was about 
half way down the pack and vanished after I removed the cell, cleaned and 
replaced it.
The cell was visually perfect and like Collin, I wondered if there was some 
imperfection in the plastic to allow leakage. These are 100Ah cells and the 
plastic seems to be very thick but just a tiny sliver of conductive material in 
the case would be enough to cause the fault.

  From: Collin Kidder via EV 
 To: Rick Beebe ; Electric Vehicle Discussion List 
 
 Sent: Thursday, 2 June 2016, 14:25
 Subject: Re: [EVDL] Ground Faults
   
Yes, I've had this same trouble with LiFePO4 cells (Thundersky). I
believe that the cases might be ever so slightly conductive. Also, the
car was in a somewhat salty environment by the ocean and sea mist and
dirt caused a build up of conductive material over the top of
everything. So, I cleaned the tops of all of the cells, especially
around the terminals. This helped quite a bit. I still ended up with a
small amount of ground leakage but much better than it was. I don't
know that it can be very easily fixed for good with Thundersky cells.
I'd probably have to insulate every single cell from each other and
the case.

On Wed, Jun 1, 2016 at 11:56 PM, Rick Beebe via EV  wrote:
> When I had a lead pack in my truck I had rampant leakage from the pack to
> the frame. I think the acid mist and dirt are conductive. I kept trying to
> find the culprit battery by segmenting the pack and the leak would literally
> just move around.
>
> And I had the same problem as you--it was tripping the GFCI outlet. I had to
> take out the GFCI outlet and install a regular one. (The truck had a 110v
> Russco charger in it).
>
> I don't think LiFePo4 cells are as susceptible although I have heard several
> stories of different makes having conductive cases. When I put lithium in
> the truck put all the cells in insulated boxes. If I have a ground fault now
> it will most likely be carbon buildup in the motor.
>
> --Rick
>
>
> On 6/1/2016 11:48 PM, John Lussmyer via EV wrote:
>>
>> I mean EVERYTYHING other than the charger.
>> There are contactors on both sides of the pack, so the controller and
>> motor are fully disconnected.
>> I also disconnected the volt/amp meter, and BMS (12v power) as well.
>> Also disconnected the "battery +" wire to the zilla hairball.
>> Unhooked the DC-DC.
>>
>> I'm wondering if I'm getting dirt/damp leakage from the pack to the frame.
>>
>> On Wed Jun 01 18:08:15 PDT 2016 ev@lists.evdl.org said:
>>>
>>> Could you be a little more detailed? You disconnected everything from
>>> what? Each other? The battery pack? Etc?  If you have a series wound DC
>>> motor then carbon build up from the brushes can create a path.
>>>
>>> Sent from my Verizon, Samsung Galaxy smartphone
>>>  Original message From: John Lussmyer via EV
>>>  Date: 6/1/16  7:35 PM  (GMT-06:00) To: Electric Vehicle
>>> Discussion List  Subject: [EVDL] Ground Faults
>>> Well, I've discovered that my truck has a ground fault of some kind in it
>>> somewhere.
>>> For a long time, I've been charging off the Welder outlet in my shop.  I
>>> recently installed a nice big 240v 60A GFCI breaker for a charging outlet at
>>> the house.
>>> The GFCI trips every time I try to charge.  It doesn't trip if I plug a
>>> welder into the outlet.
>>>
>>> Poking around the pack with a voltmeter, I get some solid voltage
>>> readings to the frame of the truck.
>>> So, I started disconnecting things.  Disconnected everything except the
>>> charger (kinda need that!).
>>> Still trips the GFCI.
>>> Still getting weak voltage readings from various points in the pack.
>>> (Not always consistent, not always constant.)
>>>
>>> Running out of ideas...
>>>
>>> --
>>> Worlds only All Electric F-250 truck!
>>> http://john.casadelgato.com/Electric-Vehicles/1995-Ford-F-250
>>> ___
>>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
>>> http://lists.evdl.org/listinfo.cgi/ev-evdl.org
>>> Read EVAngel's EV News at http://evdl.org/evln/
>>> Please discuss EV drag racing at NEDRA
>>> (http://groups.yahoo.com/group/NEDRA)
>>>
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Re: [EVDL] Ground Faults

2016-06-02 Thread Lee Hart via EV


Cor van de Water via EV wrote:

One solution is to make sure you have a good ground connection and not use GFCI.


That was my solution for years with floodeds. Use an isolation 
transformer. Plug the charger into it. It's a straightforward and safe 
solution.


I still have some big 2kw 120/240vac toroids for $50 you need one.


The US standard is ridiculously sensitive at 5 mA while in Europe the 
residential
GFCI trigger at 30 mA.


Where you set the standard depends on what you consider an "acceptable 
risk" for serious injury or death. 1 death per 100 incidents? 1 in a 
thousand? 1 in a million?


Hospitals use a very low 0.5ma standard, because an infant or invalid in 
bed is already weak, and can't remove themselves from the source of the 
shock. They want the risk to be essentially zero.


5ma is reasonable for small devices and where kids, the elderly, or 
infirm are involved. It's painful, but very unlikely to be fatal. 
Allowing a higher current reduces the cost of meeting it, so they traded 
off the cost vs the benefit.


30ma is pretty high. That's enough to kill even a normal healthy person 
under the right circumstances. I suspect this was chosen to minimize 
cost of compliance. It's also easier to meet for large machines, where 
there are many possible leakage paths (like an EV with hundreds of modules).



Success hunting the leakage ghosts!


There's something strange
Doing under the hood
Getting shocks and pains
And it don't look good
Leaky posts to ground?
And they can't be found?
Who ya gonna call?
POST BUSTERS!

...I ain't 'fraid of no posts! :-)

--
"IC chip performance doubles every 18 months." -- Moore's law
"The speed of software halves every 18 months." -- Gates' law
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
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Re: [EVDL] Ground Faults

2016-06-02 Thread Jukka Järvinen via EV

This leakage issue has to be resolved ASAP. It's pretty serious thing if
our cell cases create bridges to chassis. Please send me all data&pictures
of these cases.
-Jukka
President in Europe
TSWEG

torstai 2. kesäkuuta 2016 Lee Hart via EV  kirjoitti:

> Cor van de Water via EV wrote:
>
>> One solution is to make sure you have a good ground connection and not
>> use GFCI.
>>
>
> That was my solution for years with floodeds. Use an isolation
> transformer. Plug the charger into it. It's a straightforward and safe
> solution.
>
> I still have some big 2kw 120/240vac toroids for $50 you need one.
>
> The US standard is ridiculously sensitive at 5 mA while in Europe the
>> residential
>> GFCI trigger at 30 mA.
>>
>
> Where you set the standard depends on what you consider an "acceptable
> risk" for serious injury or death. 1 death per 100 incidents? 1 in a
> thousand? 1 in a million?
>
> Hospitals use a very low 0.5ma standard, because an infant or invalid in
> bed is already weak, and can't remove themselves from the source of the
> shock. They want the risk to be essentially zero.
>
> 5ma is reasonable for small devices and where kids, the elderly, or infirm
> are involved. It's painful, but very unlikely to be fatal. Allowing a
> higher current reduces the cost of meeting it, so they traded off the cost
> vs the benefit.
>
> 30ma is pretty high. That's enough to kill even a normal healthy person
> under the right circumstances. I suspect this was chosen to minimize cost
> of compliance. It's also easier to meet for large machines, where there are
> many possible leakage paths (like an EV with hundreds of modules).
>
> Success hunting the leakage ghosts!
>>
>
> There's something strange
> Doing under the hood
> Getting shocks and pains
> And it don't look good
> Leaky posts to ground?
> And they can't be found?
> Who ya gonna call?
> POST BUSTERS!
>
> ...I ain't 'fraid of no posts! :-)
>
> --
> "IC chip performance doubles every 18 months." -- Moore's law
> "The speed of software halves every 18 months." -- Gates' law
> --
> Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
> ___
> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
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> Read EVAngel's EV News at http://evdl.org/evln/
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> http://groups.yahoo.com/group/NEDRA)
>
>
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Re: [EVDL] Ground Faults

Re: [EVDL] Ground Faults

Re: [EVDL] Ground Faults

Re: [EVDL] Ground Faults

Re: [EVDL] Ground Faults

Re: [EVDL] Ground Faults

Re: [EVDL] Ground Faults

Re: [EVDL] Ground Faults

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