Fooljoe is correct as relates to my generator experience. I don't believe there was any "grounding" issue, only that the generator's output regulation was so poor, at the instant the "L2" EVSE connects to the car's OBC, that it badly bogs down and momentarily fails to regulate output voltage and frequency. These two parameters dip down so low that the car sees it as a impending brownout condition causing charging to immediately abort. Unfortunately, charging does not attempt to resume after this happens should the generator try to recover. Instead, you must unplug the EVSE from the car and essentially "reset" the car's charging system. This doesn't help, because the same thing will just happen again and your car never gets charged.
The only possible solution is to use a much more powerful generator, capable of holding up during larger load surges, or one that has "precision" output regulation or both. The generator I tried only had a 3500 watt rating (4400W surge) apparently not enough to compensate for an initial 240V load surge presented by the OBC in the car (RAV4 EV).
I believe the "heater trick", when the timing is just right, (which is more likely to be hit or miss), can be used to counteract the effect of a surge and keep the generator's output closer to nominal conditions, thus preventing the would-be brownout event.
Last edited by dsinned
on Mon Oct 27, 2014 7:31 pm, edited 1 time in total.