Jonseo wrote: ↑
Fri Feb 14, 2020 7:58 am
...will the car lower the input to 15A?
Yep. That's one of the main purposes of the J1772 standard -- so that EV owners don't have to worry about matching capacities of EVSE and cars. The EVSE and car work together so that the maximum safe charge rate is not exceeded in any given combination.
The installer of the EVSE of course has to make certain that the EVSE is matched to the appropriate wiring and the car is not a consideration here; installer must ensure wiring is capable of handling 125% of the EVSE's maximum rated current even if the owner has a car that consumes less. This ensures safety in case another more capable car is plugged in to that EVSE in the future, and any device that consumes high current for a long period of time is only allowed to draw 80% of the circuit's power rating.