#6 Romex is totally fine for a 50A circuit, because the rating of that cable is up to 55A. People get into problems trying to do 60A circuits with it.We are in the process of building a new home, have a 2021 Model Y and are planning on having a MEMA 14-50 and deicated 50 amp breaker installed from the get go. That being said, based on the comments I've read on this forum, I am not certain the electrician that the builder has hired is install the NEMA outlet using the correct materials. What makes me question this is his reference to the #6 Romex he plans on using. Please see the information we received from him via email below. Any thoughts or comments would be greatly appreciated.
Comments from the installing electrician:
"Hey guys,
Most of the cost on these is the wire itself. To achieve 50 amps I'll have to run #6-3 Romex.
For up to 100 linear feet of wire, 2pole 50 amp breaker in panel, 2gang box with a NEMA 14-50 outlet and plate- $1325.00 per unit installed."
The one other thing that is a little touchy is that electric code is going to require using an expensive GFCI breaker for an outlet to charge an EV. It's kind of an annoying requirement, and a lot of places are out of stock and having a hard time getting them. And please specify to not use a super cheap-o Leviton brand outlet. Any of Bryant, Cooper, or Hubbel would be fine.