TonyWilliams said:
The Tesla 50 amp plug already signals and provides 40 amps.
As it should, for a 50 amp circuit. But I'm talking about a 40 amp circuit, for which the MC should signal 32 amps.
miimura said:
6-50 and 14-50 are inherently 50A outlets, so they should have wiring and breakers that match that rating. So, they should never have a 40A breaker. I think the situation you ponder as being a problem should never happen.
My understanding is it's actually quite common (
and allowed by the NEC) to have a 40A circuit with a 50A receptacle installed, the reason being that there aren't really any standard 40A plugs/receptacles. Non-hardwired versions of 30A EVSEs almost always come with a 6-50 plug, and call for a 40A circuit with a 6-50 receptacle. Other applications that might use a 40A circuit with a 50A receptacle could include an electric range or other appliance.
davewill said:
When using one with a Model S, you would use the controls in the car to manually dial down the charge rate. I don't think the Rav has that feature (does it?). Of course if the reason someone has such a circuit is for an EVSE, you could always just plug into that EVSE. Otherwise...perhaps it might be possible to hack one of the 50a adapters to signal 40a to the MC?
I know that's what a Model S driver would do, but the Rav doesn't have this feature. Obviously if there were already a 30 amp EVSE you could use that instead (although it might be nice to squeeze out the extra 2 amps), but I imagine a scenario where somebody moves into a house where a 30A evse was installed on a 40A circuit with a 50A receptacle, but the previous owner took the EVSE with him. Or maybe you want to sell your old 30A EVSE and use a Tesla MC on the same circuit. Or perhaps you might want to charge at a friend's house where there's a 40A electric range or other type of circuit with a 50A receptacle. Probably for occasional usage it's fine to just go at the full 40A on a 40A circuit, but for any sort of regular usage of course that's not a good idea. It's interesting that Tesla doesn't seem to provide any sort of adapter to facilitate 32A charging when encountering a 40A circuit.
EDIT: Actually I just found that Tesla
does provide adapters for 32A charging in the European market, so it seems clear that a 14-50 or 6-50 adapter could somehow be "hacked" to cause the MC to generate a 32A pilot, or maybe an adapter from one of these European adapters to a 14-50 plug could do the trick, or maybe not if the European MC is configured differently.
EDIT 2: Ok the Euro thing probably wouldn't work because the Euro MC can work on 3-phase and so is probably completely different. But hacking a 14-50 adapter might still be an option.
