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 <ev@lists.evdl.org> 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 <ev@lists.evdl.org> 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 >>>> <ev@lists.evdl.org> Date: 6/1/16 7:35 PM (GMT-06:00) To: Electric Vehicle >>>> Discussion List <ev@lists.evdl.org> 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) >>>> >>>> -------------- next part -------------- >>>> An HTML attachment was scrubbed... >>>> URL: >>>> <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20160601/796e9785/attachment.htm> >>> >>> >>> -- >>> >>> 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) >> >> _______________________________________________ >> 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) > _______________________________________________ > 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) > _______________________________________________ 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)