Every time I attemp to write a response either my laptop dies, my 4 month old cries or my iPad dies. So this is my 4 attempt and I'll keep it brief for the time being since I'm on my iPad.
As for my first step, I did simply change out the pigtail and jumper the second leg of 240 to the output wire which was on the neutral lug. The ESVE only cares about current, not voltage. The car detects the voltage. The ESVE is just a smart extension cord. I did initially run my new jumper leg through the CT, but the charger didn't like that.
There are 2 paths in the ESVE, high current, and control. The charging path, from what I can tell, is perfectly capable of 240 VAC. The relays are rated at 250VAC with 12 volt coils so no issue there. The control path has a 120 to 20.9 VAC transformer. This is where the mod must take place. Since I'm not de-potting my board and tapping into the DC bus we need to insert some device which always delivers 20.9 vac to the board for the control. To make the mod easy and safe, the best way is to use a 4 wire 12 ga cable and add an additional relay. I have parts on order from digikey at the moment. Basically I plan on adding a relay with 1 form C (1NO/1NC)contact and a 240 coil. So the method will wire the first hot, neutral, and ground as originally wired, except the neutral will also be wired through the relay on the normally closed contact. The coil will be wired to both hots for 240 and the normally open contact on the relay will be wired to the other hot leg. The main contact on the relay will be wired to the white(originally neutral) wire on the J1772 cable. This always supplies the step down transformer with 120 so the control electronics don't burn up, and if 240 is present, the relay closes and applies the second hot leg to the J1772 connector allowing for 240 charging.
Right now i simply have 240 wired to the J1772 connector. One leg right now is always hot on the connector which obviously isn't ideal, but hey, so is any extension cord that you plug in right? It's not that terrible. The other leg gets closed in when the relay closes and charging begins. Very simple. My above plan is what I intend on doing in the long run for a mod. I already have input capture/output compare code written from another project that I am going to use to extend the pulse to allow for up to 20 amps. The charger only uses up to 16, however, if you want to use climate control while plugged up you will need the extra power. I am using a fresscale MC9S12 automotive grade microprocessor. I just need to build the circuit with proper resistances based on the J1772 standard. Right now, I'm just trying to finaize a cheap safe way to implement 120/240 charging. So far, it looks that the new 4 wire pigtail and 240VAC coil form C relay will do the trick.
ESVE (EV Project) Approved: 3/24/11
Blink Install: 7/20/11
Delivery: 8/4 -> 8/5 -> 8/11 -> 8/4 ->8/5 -> 8/3
Took delivery 8/6/11 Super Black SL-e