I will be installing a Tesla wall charger in the garage and have a few questions about the codes and such. It will have a 100 amp breaker and it will be pulling 80 amps for 2-6 hours at a time so with that in mind I am rating my wire as "constant load".
I will be installing it about 2ft from the breaker box and will run the wires partly in the wall and partly in front of the Sheetrock. Now I believe the codes call for all wiring to be in some sort of conduit when inside the wall. Can I just use that blue plastic stuff for that portion? And for the run outside the wall what is the rules for that?
Also because it would be a million times easier is there a way to go through the stud? I mean I guess I could pull off the sheetrock cut a hole and replace it. Bear in mind it's a garage and the walls are unpainted or anything just plain siding. Also if it was to stay in the wall I could easily pull it through the back of the charger just like an outlet box.
The image is a rough sketch of what I'm planning on doing.
Best Answer
With a normal cable, you'd use the same rules as NM
The normal cable for this job would be a type SER (Service Entrance, Reinforced) cable. While a typical SER cable for a 100A circuit would use 1AWG aluminum wires with a 3AWG aluminum ground, the Tesla charger is incompatible with aluminum wire, so you'll need to use a copper SER cable with 3AWG wires and a 5AWG ground instead. Anyway, because this is a SE cable, we look to NEC 338.10(B)(4) for the rules:
As a result, we follow the same rules as NM cable when installing this stuff, including the use of nail plates to protect it when it runs through notches or holes in studs, unless those holes are more than 1.25" from the edge of the stud, as per NEC 300.4.