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Scary issue with Nema 14-50 adapter melting


Oct 9, 2012
If it's the same unit that was burnt by the outlet, it could easily have been damaged enough to be causing a poor connection on that side. Definitely replace it.

If you check out my pics you will see it fully melted the one terminal and also the adapter. As I said, I replaced both the outlet and the adapter, but with a Leviton outlet rated to 75C. Cord was not damaged at the adapter.
Last edited:


Supporting Member
Apr 8, 2014
New Hampshire
This is from another post

Please don't hack off the UMC's wall plug socket without understanding that there is a fourth control pin with the following resistance values to ground:

Tesla UMC Plugs Resistance

40 amps - 9.08k ohms

24 amps - 33.16k ohms

16 amps - 75k ohms

12 amps - 140k ohms
I'm adding this datapoint to every thread where I see this table -

32 amps - 20k ohms (measured from a Canadian 14-50 adapter)
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