Wire size for wall charger

[ucmndd]

Do you ask a brain surgeon to elaborate on how specifics of the plan do the surgery?

Abso-freakin-lutely, and I’d ask more than one to boot.

NEC 110.3(B)

Installation and Use. Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.

Thank you, this is genuinely informative and useful. While most have no particular interest in hobbyist brain surgery, plenty of us are interested in being educated, informed, and capable of performing electrical work in our homes and the regulations that govern it. Let’s be honest, electricity is not brain surgery, and the whole point of this forum we all participate in is to exchange information.

We will diverge a bit on the clarity and explicitness of the Tesla instructions and what they intend to convey, but hey, language is where most things break down.

 

[qdeathstar]

plenty of us are interested in being educated, informed, and capable of performing electrical work in our homes and the regulations that govern it.

I will argue you are not capable. Knowing how to turn a screw driver and watch YouTube videos is not enough. You don’t know the right questions.

You have already been shown there is danger in what you don’t know.

 

[GSP]

The only concern here is this, the very first line: "For maximum power output, install a standard double pole 60 amp circuit breaker". So the manual says to use 60A breaker but does not say that you can't use a higher breaker if that in compliance with the code

The concern I would have with using a breaker rated more than 60 Amps would be that the HPWC itself is not designed for higher currents. That could lead to a “thermal event” inside the HPWC if more than 60 Amps were drawn, say due to a partial short, and the breaker did not blow.

I am not an electrician or EE. I would advise to pay close attention to advice given by said experts, several of whom spend their free time on TMC helping others. Don’t be the horse that died of thirst, after being led to water.

GSP

 

[MN-MS100D]

I am PE and an EE, and offer the following opinions to further the agitation already in progress:

1) The #3 wire is too large to be terminated at the lugs inside the HPWC, so giving it a haircut is not allowed and is not Code compliant.

2) Installing a 100A circuit to the HPWC itself is not a Code violation (except for #1 issue above). The wire to the EVSE is protected by the 100A breaker, and the downstream wiring between the HPWC to the EV is protected by internal 60A supplemental fuses. It does not serve any useful purpose to oversize the circuit for this installation, but it WILL run cooler and at lower voltage drop.

3) A strong argument could be made that the busing and lugs at the HPWC are not rated for 100 amps, and thus NOT compliant. If that is the case, #2 above is wrong. 80 amps might be the max rating. If that is the case, the 100A breaker would need to be replaced with an 80 amp breaker in the panel. Since the max circuit allowed to the HPWC varied over the years, I would say the maximum setting of the HPWC per the owners manual dictates the maximum circuit allowed to be run to the HPWC.

 

[qdeathstar]

I am PE and an EE, and offer the following opinions to further the agitation already in progress:

1) The #3 wire is too large to be terminated at the lugs inside the HPWC, so giving it a haircut is not allowed and is not Code compliant.

2) Installing a 100A circuit to the HPWC itself is not a Code violation (except for #1 issue above). The wire to the EVSE is protected by the 100A breaker, and the downstream wiring between the HPWC to the EV is protected by internal 60A supplemental fuses. It does not serve any useful purpose to oversize the circuit for this installation, but it WILL run cooler and at lower voltage drop.

3) A strong argument could be made that the busing and lugs at the HPWC are not rated for 100 amps, and thus NOT compliant. If that is the case, #2 above is wrong.

View attachment 878180

I think everyone agrees with point one, the suggestion to give it snip was a joke.

Point three is spot on, but in any case the instructions specifically tell you which breaker size to use and to be code compliant you must follow manufactures instructions. You can larger sized wire installed on a 60 amp breaker to achieve the same benefits mentioned in your second point.

 

[ucmndd]

I will argue you are not capable. Knowing how to turn a screw driver and watch YouTube videos is not enough. You don’t know the right questions.

You have already been shown there is danger in what you don’t know.

All work I’ve done has been permitted, inspected, and passed without any issues. I understand you have a strong vested interest in protecting the perceived value of your trade license and perpetuating the myth that anyone other than a licensed electrician is a reckless threat to themselves and others, but I’m comfortable with that risk.

 

[qdeathstar]

All work I’ve done has been permitted, inspected, and passed without any issues. I understand you have a strong vested interest in protecting the perceived value of your trade license and perpetuating the myth that anyone other than a licensed electrician is a reckless threat to themselves and others, but I’m comfortable with that risk.

But you’ve been outed as someone who is misinformed about the code requirements. It will work is far different than it is correct.

 

[ucmndd]

But you’ve been outed as someone who is misinformed about the code requirements. It will work is far different than it is correct.

I suppose you can take that up with the county inspector that passed all my work and certified it as correct?

A owner/builder does not need to memorize the entire NEC to safely and competently perform basic electrical work - just the parts relevant to the work being performed. Permits and inspections are a sensical backstop to ensure compliance. The vast, overwhelming majority of AHJs in the country agree with this principle and allow property owners to perform their own work.

Anyway, this is getting off track and I’ve said my piece. I’ll be sure to thank you for your selfless service the next time Licensed Electricians Day comes around.

 

[dbldwn02]

But you’ve been outed as someone who is misinformed about the code requirements. It will work is far different than it is correct.

A licensed electrician installed 10 GFCI outlets when my house was built 2006. It's passed inspection. Two had loose connections on them and failed in the first 2 years. I went and checked the rest and low and behold, all of them were loose. I know how to read, so looking stuff up in the NEC and NFPA isn't too hard. They write it to a 5th grade reading level for a reason.

When it comes to my family's safety, I trust myself (with inspector oversight) over someone who has no vested interest in said safety. Installed/replaced dozens of outlets, including my NEMA 14-50 without a single issue. 5 years running.

There will always be jobs for the trades, just not in my house.

 

[dbldwn02]

Sorry. Forgot to mention the licensed electrician also left all the kitchen outlets loose since he couldn't use the push in connections due to it being a 14awg wire. Lol. Pics for proof... Never pulled more than 1500 watts on this circuit. Toaster or air fryer at worst

 

[MN-MS100D]

Wow. He got the hot and neutral wires reversed on that outlet. Not a very good electrician if he did that wrong, and also left them loose.

 

[dbldwn02]

Wow. He got the hot and neutral wires reversed on that outlet. Not a very good electrician if he did that wrong, and also left them loose.

I could see how it looks like that but the white wire actually turned black. Lol! Wires were correctly connected, at least.

 

[jdr93]

he said he had a license. were his pants on fire?
he certainly did his best to burn your house down.

 

[qdeathstar]

I suppose you can take that up with the county inspector that passed all my work and certified it as correct?

Did he pass it with a 100 amp breaker installed?

A owner/builder does not need to memorize the entire NEC to safely and competently perform basic electrical work - just the parts relevant to the work being performed. Permits and inspections are a sensical backstop to ensure compliance. The vast, overwhelming majority of AHJs in the country agree with this principle and allow property owners to perform their own work.

I’m aware. Just because you can do something doesn’t mean you should. Like Musk running a social media company with no apparent social skills, for instance.

Anyway, this is getting off track and I’ve said my piece. I’ll be sure to thank you for your selfless service the next time Licensed Electricians Day comes around.

I charge a lot for my service. Not selfless.

 

[qdeathstar]

Sorry. Forgot to mention the licensed electrician also left all the kitchen outlets loose since he couldn't use the push in connections due to it being a 14awg wire. Lol. Pics for proof... Never pulled more than 1500 watts on this circuit. Toaster or air fryer at worstView attachment 878213

View attachment 878214

You can’t even use 14 gauge wire in a kitchen. But certainly being licensed doesn’t necessarily make you a good electrician no more than a drivers license makes you a good driver.

 

[qdeathstar]

A licensed electrician installed 10 GFCI outlets when my house was built 2006. It's passed inspection. Two had loose connections on them and failed in the first 2 years. I went and checked the rest and low and behold, all of them were loose. I know how to read, so looking stuff up in the NEC and NFPA isn't too hard. They write it to a 5th grade reading level for a reason.

When it comes to my family's safety, I trust myself (with inspector oversight) over someone who has no vested interest in said safety. Installed/replaced dozens of outlets, including my NEMA 14-50 without a single issue. 5 years running.

There will always be jobs for the trades, just not in my house.

How did you make sure the specific person who came out to your house was liscensed?

 

[davewill]

By that logic could I put a nema 14-50 wire myself on a wall connector and plug it in? Circuit is NEC compliant.

Maybe I'm wrong but I think insurance might try to deny a claim if equipment is hard wired installed against manufacturers instructions. I've seen insurance denied for what seems to me to be far less.

Happy to admit I'm not an expert with any of this so others should know more than me. Might take an insurance lawyer to know for sure.

The only reason you can't is because the manufacturers instructions do not allow that install method. Otherwise, it would be code compliant. Indeed, many EVSEs (like one of the ones I own) are intended to be installed in exactly that way.

Tesla even sold (and maybe still sells) a version of the wall connector that had a 14-50 plug on it.

 

[dbldwn02]

Tesla even sold (and maybe still sells) a version of the wall connector that had a 14-50 plug on it.

Yup! I got one. Love that thing. 40amp charging for 5 years straight...no issue.

 

[dbldwn02]

You can’t even use 14 gauge wire in a kitchen. But certainly being licensed doesn’t necessarily make you a good electrician no more than a drivers license makes you a good driver.

Sorry. Meant 12...12 doesn't fit in the back-stab. The rest of the house is 14 and none of the back-stab have failed. I'm slowly switching them out to get rid of the stupid child proof outlets.

 

[qdeathstar]

Sorry. Meant 12...12 doesn't fit in the back-stab. The rest of the house is 14 and none of the back-stab have failed. I'm slowly switching them out to get rid of the stupid child proof outlets.

Getting rid of the tamper proof outlets is a code violation.