I am planning to install a NEMA 14-50 outlet in my garage on a 40A breaker (Romex 8/3 cable from breaker to outlet) for use with an electric car charger. The charger will charge my wife's car in the wee hours overnight.
The charger also has the option of coming with a NEMA 6-50 plug rather than the 14-50, if that's a better option.
Sometimes in the winter, I like to work in the garage. So, I got a plug-in heater that has a NEMA #6-30 plug and requires a 30A circuit.
I'd like to be able to unplug the charger and plug in the heater. Since the heater draws less power than the charger, as long as the circuit is sized for the charger I think this should be OK. Assuming so, here are what I see as my options:
Chop the 6-30 plug off the heater and replace with a 14-50 (or 6-50) plug.
Get an adapter from 6-30 to 14-50 (or 6-50).
Would appreciate any thoughts on this: Is it feasible? Are there better options (aside from running a separate circuit for the heater)? Is there any advantage to getting the charger with a 6-50 rather than a 14-50? Is 8/3 Romex sufficient?