Andolyn said:
So what I'm hearing is run the 40amp breaker with #6/2 or do i need 6/3? gauge wire using a 14-50 plug? Might give me a little future proofing? Will have an adapter for the 30 amp male to the 14-50 receptical? Any ideas for best $$ on the 6/3? . ill need les than a 100' but want to but 100' roll
Nope, basically you have 2 options:
1. 50 amp breaker and 14-50 outlet with 6/3 wire, and use an adapter to connect your EVSEupgrade with L6-30. Recommended for future proofing and versatility.
2. 30 amp breaker and L6-30 outlet with 10/2 wire, or 6/2 or 6/3 for future proofing. Works fine for your EVSE up to 24 amps and you can save a few bucks on wire with 10/2, but most of the cost is labor anyway, so why not go big?
Your receptacle should match your breaker and wire. So while you don't need the extra conductor in 6/3 for charging purposes, the 14-50 receptacle advertises that it's there, so it must be there. Plus it gives you some added versatility - the neutral would allow you to build an adapter to use high-power 120v appliances or power tools from the outlet if you'd like, or you could plug in an RV should the need for that ever arise. If none of that matters to you you could go with 6/2 and a 6-50 outlet.
Likewise, you can't put a 30 amp outlet on 40 amp breaker, and while you
can put a 14-50 on a 40 amp breaker, that would be ill advised. I wouldn't recommend a 40 amp breaker for just about anything except hardwiring a 30 amp EVSE.
