So I use a now-venerable Juicebox JB-40 that I got with our 2017 Chevy Bolt a few years ago. We ran it at 32 amps until my wife noticed that the plug was hot to the touch. It was hot enough, in fact, to soften the plastic a little -- scary. This was back in 2018. I chalked it up to a bum unit and we replaced the 14-50 socket with a newer one. Of course, it happened again and with a little googling I rapidly learned that it was probably just the under-specced and heavily cost engineered outlet from Leviton. We set the Juicebox to de-rate itself to 20 amps and everything was fine. We charged that Bolt nightly, shitty Leviton socket and all, until we sold the car back to Chevy during Batterygate last year.

Well, now we have another EV (a Model Y) and we've got a proper Hubbell socket in there. The Hubbell contactors are indeed full sized, which was refreshing to see. A few nights ago, I finally got around to telling the JB-40 to allow its full current, and had the car draw 32 amps for a few minutes. Eff me, the 14-50 plug got hot to the touch again!

The system seems to run just fine at 20 amps -- the plug gets maybe 10C above ambient, prongs maybe 20C above ambient. But based on what I'm observing I'd never run 40 amps through there unattended. (P = I² R, so I'd expect something like 80C above ambient for the prongs themselves! Yikes!) Yes, the JuiceBox is UL-listed; and, yes, the circuit is a proper 50-amp circuit with overspecced 6-gauge wire.

If you charge through a 14-50 socket -- what EVSE are you using? And how hot does the plug run at, say, 30 amps? JuiceBox has a pretty great reputation, but I'm starting to wonder if the plug itself is bad, or if 14-50 plugs just generally run hot.