I had an electrician install a 50amp breaker in a subpanel that runs a 14-50 outlet. I use a Tesla Wall Charger and my M3 RWD will only charge at 32 amps anyway. But when I used it the first time after about an hour the breaker tripped. It was so hot I could not touch it even for a second. The breaker the electrician put in was faulty and was a compatible, but not the same brand as the panel. I replaced it with the same brand and the problem was solved. Even the 50 amp breaker running 32 amps gets warm to the touch but that is expected. I also cleaned the breaker bar with a green pad. I have a Hubbel 14-50 outlet, and while it cost me, that is a nice robust outlet. Good idea to check the temperature of the breaker, outlet, wire etc to see if things are overheating. The good news is that the breaker did what it was supposed to do and tripped open.
-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
40A Breakers Get Hot When Charging
- Thread starter Bikeman
- Start date
I run the outlet check every 6-months and pull the socket from the receptacle. The last time I did was Jan. Everything was fine and clean.
I was usually running 36A and doing 40A last night and found it becomes “hot” than usually. It is why I unplugged to check it again. Just placed the order for Hubbell 9450a 14-50. I’m lucky to find this issue ahead of the bigger trouble.
Just saw this thread below.
Burnt nema 14-50 plug and breaker tripped
I have been using juicebox pro 40 EVSE (an older model) for my BMW i3 for two years without any problem. It’s rated 40A max on a 50A breaker. Now I use it to charge my tesla m3 LR RWD with a J1772 adapter. I checked the charging current on tesla touchscreen and it showed that current ramping...
teslamotorsclub.com
Here's a post showing that my outlet went from 186 degrees to 154 when replacing a Leviton with a Hubbell. This was with 32 amp charging.
teslamotorsclub.com
HPWC Installed
The EVSE will draw the maximum current from the circuit for the duration of the charging period that could last more than 8 hours. Do you have a source you can share? Every place I look sells extension cords designed for EVSEs, and of course the TWC will use of 80% of the circuit rating which...
teslamotorsclub.com
I'm "slow charging" at the moment, at 235v and @ 16A with the JuiceBox40. Just felt the breaker. One side is warm, the other is cool. That tells me, I believe(?), that one leg of the system is giving more resistance than the other leg. What can cause that? Could it be any connection along that leg from the breaker to the 14-50 outlet? At 20A output, I could detect the entire breaker becoming warm. 16A seems to give more of a clue.
Yet to do: discover what brand 14-50 outlet is under the cover and inside the weatherproof hooded box outside. My guess is a Leviton. That will involve some disassembly. That will happen when the guy comes back and we switch out the breaker to the Siemens and test that for heat at full 32A output.
Yet to do: discover what brand 14-50 outlet is under the cover and inside the weatherproof hooded box outside. My guess is a Leviton. That will involve some disassembly. That will happen when the guy comes back and we switch out the breaker to the Siemens and test that for heat at full 32A output.
From the pic the guy posted in 2018, and from what I found in mine, this particular leg/hole in Leviton NEMA 14-50, had the worst melting/burning marks.
Attachments
Yes. One side, (top), or half of it. I'm very much leaning on replacing everything from the breaker to the 14-50 with 6g and a Hubbell, faceplate, and hopefully that will fit in the outlet box (seen in the first post).
Amazon has the Hubbell for only $88.99 right now. From the pic of your box in your first post, you should double check that the right faceplate is available for your box.
The Leviton is 2.15" diameter and the Hubbell is about 2.5" (2 31/64").
I hope that everything works out for your project.
The Leviton is 2.15" diameter and the Hubbell is about 2.5" (2 31/64").
I hope that everything works out for your project.
Interesting. To a layman, it does sound like the “hot side” might be slightly loose and the termination could use a good scrub and tightening … or just a new breaker.
It’s not necessary to change everything else out to address this particular issue unless you want to upgrade for completeness’s sake.
stopcrazypp
Well-Known Member
Amazon also now sells the Bryant for less than $50. Why not buy the Bryant given it's also made by Hubbell and is pretty much identical?
Amazon.com
If you want more affordable and varied face plate options, I detail it in this post (including ones for exposed boxes)
Master Thread: Definitive 14-50 NEMA Outlet Guide
I took the weatherproof cover off the outlet today and discovered, not at all to my amazement, LEVITON!
The plate around the LEVITON seems to be 2 3/8" X 3 1/2." I don't know how deep or wide the outlet box is or if I need to also swap those out for a Hubbell.
Say, that's quite the long and informative thread on outlets! Thanks for linking to that. Not sure I want to read it cover-to-cover. Hubbell / Bryant is probably all I need to know.
Last edited:
The Hubbell is long and the wires enter from the back. So you need a deep box. I bought a PVC box that was a little over 2" deep, but it was not deep enough. So I bought a 2nd box and cut ~1/2" off the front and used PVC glue and screws to extend the box. The box was then almost 3" deep and it was still a challenge to get the wires in the box.
Also I 2nd the comment to go ahead and buy the Hubbell face plate. It is not just the cut out that is different, the four screws that keep it on are not in a standard place. So only the Hubble faceplate seems to fit.
stopcrazypp
Well-Known Member
Yes, the outlet is much deeper than the standard ones. However, a standard 30+ cu in. box probably would fit the wires if you use a 2-gang. If using a 1 gang, there is no space for the wires.
I personally used a 4 inch metal box box:
https://www.lowes.com/pd/RACO-2-Gan...Square-Ceiling-Wall-Electrical-Box/5013994635
With a 5/8" deep mud ring for more box volume to better meet code, but it seems it would still fit even without the mud ring (although the metal box is perfect square so perhaps more volume than an equivalent PVC)
https://www.lowes.com/pd/RACO-2-Gang-Square-Metal-Electrical-Box-Cover/3130131
The better solution is to used a raised exposed work square cover, but they weren't available near me.
https://www.homedepot.com/p/RACO-4-...30-60A-Round-Receptacle-1-Pack-813C/202097252
If sticking with PVC, a 2 gang would be like this:
https://www.homedepot.com/p/Carlon-...ox-with-Adjustable-Bracket-B234ADJC/100315472
Here's someone on reddit using that exact model B234ADJC to install the Hubbell outlet:
The Leviton S701 I bought and suggested ($7.59 at Amazon, I found it locally too in Ace as per my post):
https://www.amazon.com/Leviton-S701-40-Stainless/dp/B003725QWU/
Is a direct clone of the $16 Hubbell SS701:
https://www.amazon.com/Hubbell-Stainless-1-Single-Receptacle-Diameter/dp/B002FYJ758?th=1
Even the name is almost the same!
https://teslamotorsclub.com/tmc/posts/6266356/
I used it with my Bryant socket and it fits just fine. I would be surprised that there would be face plates with this diameter cut out that uses a different screw placement. There seems to be only two sizes: the standard 2.156" and this industrial 2.465" (the Hubbell, Bryant, Cooper/Eaton uses this).
All great info above. Thanks!
What I'll need to do if I go with a Hubbell, is to mount a (weatherproof) box directly onto a plywood wall (without studs on the sides) and provide it with a weatherproof cover, similar to the photos in the OP. Is that going to be possible with Hubbells? Anyone have this setup outside?
What I'll need to do if I go with a Hubbell, is to mount a (weatherproof) box directly onto a plywood wall (without studs on the sides) and provide it with a weatherproof cover, similar to the photos in the OP. Is that going to be possible with Hubbells? Anyone have this setup outside?
You guys are right. My original 2-1/8” box installed in Dec 2017 barely fits the Hubbell and cables. And my cables are #6 which are stiffer and need slightly more space. So in the end I got another 1-1/2” extension ring, plus another half inch cover.
So this boosts my box depth to 4+” in the end. They don’t look beautiful but this is okay to me.
So this boosts my box depth to 4+” in the end. They don’t look beautiful but this is okay to me.
Attachments
Just the quick update. I've been using the new Hubbell NEMA 14-50 for a few days. It's great. I tried to use 32A, 36A, and 40A to charge for 4+ hours. And, comparing my old/junk Leviton's, I can feel the huge temperature drop from this Hubbell's.
As others suggested, I'm also ordering the infrared temperature gun to measure all the "hot" spots. Will post further then.
As others suggested, I'm also ordering the infrared temperature gun to measure all the "hot" spots. Will post further then.
Eric33432
Member
You should not use a Siemens breaker in a GE panel unless the panel is listed for the Siemens breaker, which is unlikely.
It is likely that one of the internal contact points inside the breaker has become pitted or burned which will cause the breaker to operate warmer than usual. It is a no-brainer to just replace it. Also check the contacts where the breaker plugs onto the panel to be sure they do not look burned or discolored.
If replacing a non-GFCI breaker that was installed before GFCI breakers were required, most jurisdictions will allow you to replace like with like, but you could install a GFCI breaker if you want to. That would be something I would do if I was removing the plug often; for a device that is plugged in and just left plugged in, I would not bother with a GFCI.
Similar threads
- Question
