Curiosity got the best of me, so I gave this a try tonight. Total success on 240 volts - no magic smoke!I'm with you though, why design for 120 when a universal design for 240 can be done for no added cost. I'm willing to sacrafice mine and have the necessary adapters, I'll test on Saturday.
Plugged into 120 volts:
Plugged into 240 volts:
Capturing some raw values from Car Scanner ELM OBD2, I was able to see that the battery pack was right around 380 volts for both tests. There was likely a bit of cabin heating going on at the time, as it was 55°F in my garage.
- Charging from 120 VAC, I was seeing 2.3 amps DC flowing into the battery pack- this is around 875 watts of net power after some being diverted to heating.
- Charging from 240 VAC, I was seeing 5.2 amps DC flowing into the battery pack- this is around 1975 watts of net power after some being diverted to heating.
To try this, I used a 6-20 outlet I have available. I made a unsafe adapter cord that should NOT be used for ANY OTHER PURPOSE besides plugging in an EV charger that is known to be dual voltage. Never ever leave something like this plugged in, as it provides 240 volts on a 5-15R, which is definitely out of line with expectations.
Here it is, green indicator light glowing, plugged into a 240 volt outlet. It was not yet plugged into the car, thus only one light lit.
A final note- the 5-15 plug on the included EVSE has two additional wires running through it to a thermistor that is embedded in the plug. So I would recommend against any modifications to that plug, such as cutting it off and replacing it.