-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
NEMA 14-50 Meltdown
- Thread starter GuyGadois
- Start date
The outlet is mounted ground up. You can sort of make out the vertical 14-50 neutral slot at the bottom of the picture. A 14-50P would not fit at all in a 14-60R without cutting off the neutral pin, which is still attached to the adapter in the picture.
That is a melted NEMA 14-50 receptacle. This thread is discussing melted NEMA 14-50 receptacles.
I thought it was a 14-60 at first, based on the flat blade at the top, but that’s how the ground pin is shaped in a 14-50 receptacle. If it was a 14-60, the neutral (bottom) pin would be hotizontal, not vertical.
Also, a misshapen ground pin would not cause the problems being discussed in this thread.
PWlakewood
Active Member
Been there done that. Had my electrician install a 14-50 outlet and had no trouble for 1 1/2 years. It would heat up but not too hot until one week I noticed that it was extremely hot but it was also 95 outside so we assumed it was because of the hot weather but while we were sitting on our deck we heard a loud pop and i ran downstairs to find our main 200 amp and 50 amp breakers both tripped. Turns out the wire inside the outlet got way too hot and melted the insulation off and shorted out. I had him rewire it and now its hard wired and there is no heat evident at all when charging.
Last edited by a moderator:
nwdiver
Well-Known Member
PWlakewood
Active Member
All wires and fittings were still tight. We took it apart together and he couldn't understand how and why it got so hot. Its on a 50 amp and I only charge at 40 amps and its on 6 gauge wire.
nwdiver
Well-Known Member
It may have felt tight after it cooled, it may have been a lot less tight at 190F than 70F, but there was clearly a high resistance connection in there.
My recommendation to people is to only use the charge rate you need. The heat generated by current is exponential. 40A produces 4x as much heat as 20A and 16x as much heat as 10A. Every charge cycle slightly expands and contracts those connections so every charge cycle is another opportunity for something to loosen. The higher the current the more thermal expansion.
PWlakewood
Active Member
Well im not the electrician but I do trust the person who installed it and I trust his word. Either way its hardwired now and no heat at all.
PWlakewood
Active Member
Watts_Up
Well-Known Member
Did you have your UMC charger hanging directly from the plug or did you use a bracket to hold its weight?
I suspect that one pin of the plug was not making a good contact, because of the weight of the UMC,
and the connection of the pin with the socket was using only a very small spot with the receptacle.
Thus, the pin started to overheat and the heat got propagated to the wire which started to melt creating a short with the metal box and conduit.
ucmndd
Well-Known Member
PWlakewood
Active Member
Instead of the plug on the end of my HPWC I had him remove that and make it permanent.
ucmndd
Well-Known Member
JPP
Active Member
I wonder what brand and level of quality your NEMA 14-50R was? The screw terminals and configuration of the wire slots makes me think that your melted receptacle is a $10 receptacle. Get the better Hubbell or Bryant one (see the Tesla spec or search these forums) which cost like $60, and look at the construction and how the wires are clamped. This is a high amperage continuous current use case. You want the best.
Similar threads
