-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
Electrician installed wall connector using Romex 8/3 + 60A breaker
- Thread starter explosive0
- Start date
Oh, OK. I saw six power wires, plus another unknown something in that conduit above, and you did say it runs through the garage in conduit, with no explanation of where this picture was, so I had no idea which line you were indicating went to the wall connector.
So...that does look like 6 gauge Romex, which is only rated to a 55A circuit rating. It's not allowed to be used for a 60A circuit like you're doing. So yep, it's a code violation. Personally, I wouldn't bother to change the wire, but I would just switch it to a 50A breaker, and change the wall connector settings to make it operate as a 50A circuit, sending 40A to the car.
dhrivnak
Active Member
Temporarily you can set the charge level to 32 amps and use it until corrected.
It’s definitely a code violation, but not a particularly dangerous one. Your call on what to do; personally I would swap the 60A breaker for a 50A breaker and drop the charge rate to 40A from 48A.
I’ll quote my earlier post here:
Exactly. The sad reality is that something like 80% of the licensed electrician 48A EVSE installs I’ve come across are incorrectly using #6 NM-B on a 60A breaker. Absolutely not code complaint, but also not particularly dangerous for most scenarios. The internal conductors on nm-b are THHN. It’s not like #6 copper THHN conductors magically lose the ability to carry a given current when they’re bundled inside a PVC jacket vs inside a conduit…
NM-B gets the 60degree column because it generally gets installed inside walls, often covered in insulation, eg scenarios where the possibility of heat buildup is much higher than a typical conduit run.
But the fact remains that the actual conductors are identical. So, as far as “dangerous” things go, a 48A continuous load on #6 nm-b is pretty low on my list. I still would personally never do it of course, but if I had such an install I wouldn’t lose any sleep over it
Here’s an example spec sheet showing that the nm-b conductors indeed meet the thhn/thwn2 90C spec: http://library.coburns.com/specs/CATALOG_Encore-Wire_71760524.pdf
Regardless of that though, because those conductors are in an nm-b cable assembly and not run bare in conduit, NEC says they’re limited to the 60C column (55A, 44A max continuous), instead of the 75C column you’d normally get to use (65A, 52A max continuous).
davewill
Active Member
Actually, if you set the wall connector for 50a, it will be perfectly safe to use while you wait to change the breaker.
the "unknown" is line coming from solar panel inverters.. into main panel..
Sorry, I should have mentioned/highlighted the wire going to HPWC... since there are many wires.
Thank you.. will charge at 40.... until the breaker changed.
Last edited:
if you didnt have any issues for the past 2 years, i wouldnt bother... i also have the same setup... i am only changing the tesla app to charge at 40amp. Earlier i was charging at 48amp and never had any issue.. the wire is running from the basement... only garage wire through the pvc conduit.
Is that electrician or the company that did the work still in business? I'd call them up, explain the situation, and if you originally asked for 48A, ask them to change the wiring.
yes, it's company and i have receipt... so he knew and used wrong wire... it has been 3 years though!!
Still something they should make right after it's brought to their attention.
I had another lic electrician stop by and check this.. and he said it's per code and if he were to do it.. he would be using the same wire.
they all saying it will pass the inspection and that's all they would go by..
I guess, I will bring down the charge rate and be safe. 40 vs 48 doesn't change much for my daily drive...
they all saying it will pass the inspection and that's all they would go by..
I guess, I will bring down the charge rate and be safe. 40 vs 48 doesn't change much for my daily drive...
Sounds like the guy hasn't read the code. 6 gauge NM-B wiring can only be used for loads of up to 55A. But since the EVSE is a continuous load @ 48A, it counts as a full 60A load, and therefore, 6 gauge NM-B wiring cannot be used to power it. So he's either forgetting that NM-B has a lower ampacity rating because the wires are bundled together and can more easily overheat, or he's forgetting that an EVSE is a continuous load, or both. My electrician used 4/3 NM-B for that exact reason.
davewill
Active Member
It may indeed pass inspection. This style of install seems to be very popular. Many electricians, including Tesla approved ones, and inspectors seem to be OK with it. We certainly haven't heard of any actual failures.
Issue is that electiciabs be taught from apprenticeship that 60 amp circuit = 6/2 nm cable because they mostly run air handlers minimum circuit ampacity always <55 amps. Don’t read the code book.
yeah, with so many people buying EV's, I don't think they have shortage of work. If I am picky, I am sure they have 10 other customers lined up anyway..
except for few people in this thread and few other threads, all customers - 95% of them accept their work since it passes inspection - and done!
except for few people in this thread and few other threads, all customers - 95% of them accept their work since it passes inspection - and done!
Similar threads
