120/0.6=200 ohm resistor. I will check for this. I'm still reverse engineering the DC path as of right now. As for the hot path, there are some tvss diodes that I'm not sure if they are good up to 240 or not. My guess is that they are not. One typically wouldn't design a circuit for 120VAC and use 240VAC TVSS diodes. They probably wouldn't do their job at 120 if they were spec'd for 240. And if overvoltage was applied to these diodes rated at 120 they would constantly be trying to short the excess energy to ground which would ultimately blow them up since they would be shorting all the time. Panasonic makes these TVSS diodes, here is the link to them:
http://industrial.panasonic.com/www-cgi ... 0002+4++WW" onclick="window.open(this.href);return false;
Notice there isn't one that convers the entire 120-240 range which is really more like 90-280 according to ANSI. So these must either be removed or an alternate path must be created for the second 120 leg of the 240 to maintain TVSS protection withing the ESVE. There is TVSS protection in the vehicle charger as well, but the J1772 recommends, if possible, to have TVSS protection on the ESVE end as well. The best way would be to add a third AC path with a third relay and another set of TVSS protection diodes from the second leg to the neutral as well. Then both are protected with respect to the neutral which should be at ground potential.
lincomatic wrote:I did some testing of the ground integrity check w/o opening mine up. I connected the ground pin of the EVSE to an earth ground (a screwdriver driven into the dirt) instead of the house ground. It still passes the ground check and works normally, even though the impedance between neutral and gnd is very high, so this rules out the idea that it's checking the for neutral shorted to ground. My ammeter shows that there's a constant ~0.6A (sounds high to me.. but my two ammeters had the same reading) current running from hot to gnd. It checks the ground continously... if you disconnect it, the green ready light blinks, and when you reconnect the ground, it goes solid again.
So.. since it doesn't try to short neutral to gnd, and *if* there's nothing in the hot path through the relays that can't handle 240V, I think it should work on 240V with a power supply that steps it down to the 20V that the control board needs.
Some questions from the photo's I've seen of the insides:
1) Why is the small relay for GFI trip test 13A? Isn't that overkill?
2) Why is the fuse 25A when the main relays can handle only 20A, it's supposed to be used on a 15a circuit, and have 12A max current draw?
3) If it has a 25A fuse, why didn't the fuse blow when Ingeneer did the 26.5A smoke test?