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For a 32 amp onboard charger, you only need a 40 amp breaker.

32A ÷ 0.8 = 40A

That is what we have been running for over four years, and the breaker stays barely above ambient. Why would you want a breaker that is less sensitive to an overload?

The wiring from our 14-50 outlet to the breaker was originally for my hardwired welder, which had a 90 amp breaker. I downsized the breaker, so the car wouldn't burn up before the breaker tripped.
If you are in the U.S., the NEC says you will supply continuous loads at not less than 125% of the nameplate rating. When you have done the math, you may round up to the next common overcurrent device rating on circuits less than 800 amps.
My personal 32 amp level two charger is connected to a 40A two pole breaker. If you upside the wire for voltage drop reasons that does not charge the receptacle or breaker sizing.
I do take issue with plugging a level one charger into a 14-50 receptacle. If there were ever an equipment failure it would probably be pretty impressive.
 

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You left some information out about the stock EVSE. It should also have an amp rating along with the voltage rating. Per NEC, you can't have a load connected to a circuit that is larger than the allowed 125%. This code is written to protect against fires and property damage. When a load is protected by too large of overcurrent protection, the end result of a device failure is fire instead of a tripped circuit breaker.
 
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