Wire gauge (AWG) for HPWC (Telsa Wall Connector)

[brkaus]

Good choice. My electrician suggested the same. When we get our 2nd Tesla, upgrade for 2 connectors is easy.
Switch out the 60 amp breaker for a 90 and chain the 2 HPWC'S on that circuit. I can't wait to upgrade!!!

4/3 romex is only good for a 70a breaker

 

[Kleenerth3]

4/3 romex is only good for a 70a breaker

#4 stranded is what OP stated, which is fine. You're right though, Romex is a different story.

 

[Kleenerth3]

My set-up...

 

[davewill]

Thanks! I'm going with 4 AWG stranded cable (4/3).

#4 stranded is what OP stated, which is fine. You're right though, Romex is a different story.

I'm pretty sure he's talking about Romex since he calls it 4/3 cable. He just means the individual wires aren't solid, which they wouldn't be at this thickness, anyway I don't think.

 

[Kleenerth3]

I was wondering about that.
Duely noted. Thanks.

 

[jebinc]

OP Update:

Installation complete using 4AWG stranded conductor 4/3 Romex. Decided to add a sub panel and whole house and sub panel surge protection as well. Thanks for the tips!

 

[gilscales]

I decided to pull the trigger on 4/3 Romex for my HPWC install. I ran the cable and am now just awaiting arrival of the HPWC on Tuesday (7/9). What did you all use?

4/3 is the correct choice when running Romex (non metallic) sheathed cable as it's only rated at the lower 60c temp ratings so 70A and the 6/3 Romex is at 55A, remember you can only use 80% of that for an EV charger as it is considered a continuous load (anything that can run over 3 hours) so 4/3 Romex is 56A continuous 6/3 Romex only 44A continuous, on a HPWC your settings for these would be 48A for 60A breaker on 4/3 or 40A on a 50A breaker on 6/3 as there is not setting for a 44A max on the HPWC.

 

[jebinc]

4/3 is the correct choice when running Romex (non metallic) sheathed cable as it's only rated at the lower 60c temp ratings so 70A and the 6/3 Romex is at 55A, remember you can only use 80% of that for an EV charger as it is considered a continuous load (anything that can run over 3 hours) so 4/3 Romex is 56A continuous 6/3 Romex only 44A continuous, on a HPWC your settings for these would be 48A for 60A breaker on 4/3 or 40A on a 50A breaker on 6/3 as there is not setting for a 44A max on the HPWC.

Thanks and yes I concur.

 

[ZOMGVTEK]

Looks good.

Some inspectors aren't too keen on running NM through conduit, others are OK so long as its de-rated.

Is THHN serving the sub in the conduit?

 

[gilscales]

Looks good.

Some inspectors aren't too keen on running NM through conduit, others are OK so long as its de-rated.

Is THHN serving the sub in the conduit?

Running the sheathed Romex in less than 10ft. of conduit for protection such as is this case here than it is up to code

 

[jebinc]

Looks good.

Some inspectors aren't too keen on running NM through conduit, others are OK so long as its de-rated.

Is THHN serving the sub in the conduit?

I only used 3’ of conduit above the HPWC, to avoid cable chaffing, otherwise the NM cable runs naked for about 35’ to the sub panel. For the sub panel conduit, I removed the 4 AWG conductors and ground from the romex as HD didn’t have any 4 Or 3 AWG THHN. You shouldn’t put Romex in conduit for thermal reasons. Less than 3’ total. The sub is protected by a 70 amp breaker and the HPWC by a 60 amp breaker.

 

[gilscales]

I only used 3’ of conduit above the HPWC, to avoid cable chaffing, otherwise the NM cable runs naked for about 35’ to the sub panel. For the sub panel conduit, I removed the 4 AWG conductors and ground from the romex as HD didn’t have any 4 Or 3 AWG THHN. You shouldn’t put Romex in conduit for thermal reasons. Less than 3’ total. The sub is protected by a 70 amp breaker and the HPWC by a 60 amp breaker.

You are good, from the NEC or National Electric Code
312.5 Cabinets, Cutout Boxes, and Meter Socket Enclosures. Conductors entering enclosures within the scope of this article shall be protected from abrasion and shall comply with 312.5(A) through (C).

(C) Cables. Where cable is used, each cable shall be secured to the cabinet, cutout box, or meter socket enclosure. Exception: Cables with entirely nonmetallic sheaths shall be permitted to enter the top of a surface-mounted enclosure through one or more nonflexible raceways not less than 450 mm (18 in.) and not more than 3.0 m (10 ft) in length, provided all of the following conditions are met:

Just has to be at least 18" and less than 10' to be code approved so everything is Bueno!

 

[jebinc]

You are good, from the NEC or National Electric Code
312.5 Cabinets, Cutout Boxes, and Meter Socket Enclosures. Conductors entering enclosures within the scope of this article shall be protected from abrasion and shall comply with 312.5(A) through (C).

(C) Cables. Where cable is used, each cable shall be secured to the cabinet, cutout box, or meter socket enclosure. Exception: Cables with entirely nonmetallic sheaths shall be permitted to enter the top of a surface-mounted enclosure through one or more nonflexible raceways not less than 450 mm (18 in.) and not more than 3.0 m (10 ft) in length, provided all of the following conditions are met:

Just has to be at least 18" and less than 10' to be code approved so everything is Bueno!

Thanks!

 

[ZOMGVTEK]

I’m not saying it’s a code violation. But I did see a few occasions where an inspector failed exposed NM entering short lengths of conduit used for mechanical protection. I’m told arguing these things with them is futile. NEC does sound rather clear on that point though.

 

[jebinc]

I’m not saying it’s a code violation. But I did see a few occasions where an inspector failed exposed NM entering short lengths of conduit used for mechanical protection. I’m told arguing these things with them is futile. NEC does sound rather clear on that point though.

Yes, I’m very comfortable with this setup, and it’s safety. I’ve read about some real butcher jobs, long lengths/runs, undersized wire, etc. - none of that here.

 

[ZOMGVTEK]

Quite a lot of DIY installs are total hack jobs and they’re almost never an issue. So I wouldn’t worry too much.

I’ve been amazed several times at the janky stuff that lasted decades without burning down. I’d probably avoid rolling the dice though.

 

[gilscales]

I’m not saying it’s a code violation. But I did see a few occasions where an inspector failed exposed NM entering short lengths of conduit used for mechanical protection. I’m told arguing these things with them is futile. NEC does sound rather clear on that point though.

I agree that if the inspector says it’s wrong whether it is or not then it is wrong, many times inspectors have had me change something because they think it is against code, I have even showed one the code and only angered him so the next time I seen him on a job it was hell to pay for sure, now no questions, they say jump and I say how high.

 

[Jones0812]

While I might have an electrician come and run the wires and hook it up, I want to run the conduit because I need to send it behind a partial wall and I am also picky on how things are run in my house...LOL

Here is what I want to do....let me know if I'm crazy.

Have about a 40' straight run from one side of the house to the other in the basement. I want to run 1" conduit from the panel to the other end of the house to a box. Run 3- #4 wires and a ground (future proof with a neutral if ever needed). then at the box switch to a 3/4" conduit to punch to outside and to the wall adapter outside. I will then cap the neutral in the box and run the 2- #4 and a ground out to the wall connector.

 

[davewill]

While I might have an electrician come and run the wires and hook it up, I want to run the conduit because I need to send it behind a partial wall and I am also picky on how things are run in my house...LOL

Here is what I want to do....let me know if I'm crazy.

Have about a 40' straight run from one side of the house to the other in the basement. I want to run 1" conduit from the panel to the other end of the house to a box. Run 3- #4 wires and a ground (future proof with a neutral if ever needed). then at the box switch to a 3/4" conduit to punch to outside and to the wall adapter outside. I will then cap the neutral in the box and run the 2- #4 and a ground out to the wall connector.

Sounds fine. Don't cut the white wire short, leave it long enough that it could be run through the wall along with the others, or go ahead and run it into the WC and cap it off there.

 

[azjohn]

My M3 SR charges at 30a on a 40a circuit using 8ga NM cable (Romex) wire. Since the SR only does 32a max charging, it's all that's needed. It's the third generation of EV (LEAF, Rav4EV, Model 3) to charge on that circuit and EVSE.

View attachment 426693

I just installed a shiny new 14-50 on a 50a circuit. It uses 6ga THHN wire in conduit and could be upgraded to 60a with just a breaker change (and removing the outlet). It charges my Rav4EV at 40a.

View attachment 426699 View attachment 426705

BTW, the answer to your question in the OP is that 6ga wire is fine for a 60a circuit if it's individual wires in conduit, but if you use NM cable (Romex) then it requires 4ga.

Nice garage....you could perform surgical procedures