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points by josephcsible 1 day ago | 0 comments

If pulling 24 amps through a TT-30 or 40 amps through a 14-50 trips a breaker, then it's the host's fault for the campground having a shoddy electrical system, not the truck driver's fault.

[–] rootusrootus 1 day ago

Approximately zero campgrounds have the capacity to charge more than one EV. They are sized for intermittent loads, just because it uses a 14-50 does not mean it is intended to support 80% steady draw.

[–] colejohnson66 1 day ago

Is that not the point of a 14-50 socket? To say that you can draw 50 amps? If you can't supply 50 amps without tripping a breaker, don't install a 50 amp socket.

[–] rootusrootus 1 day ago

At the risk of saying something obvious, the socket and the breaker are sized for the peak load, not for average load. A typical home might have 300-400 amps if you total up all the breakers even though the mains are 200A or even 100A.

Also, a bog standard 14-50 is likely not suited for 80% steady EV usage anyway. They make EV-rated 14-50s now because people keep melting the older ones. And that happens even though the vast majority of chargers won't draw more than 32A on a 14-50 due to the historical popularity of using 40A breakers for a 14-50 receptacle.

[–] arrowleaf 1 day ago

Lol in what world? Campgrounds routinely have next to no funding, if they even have power pedestals I wouldn't expect them to be wired for anything more than an RV.

[–] josephcsible 1 day ago

The entire reason we have so many different types of receptacles is so to keep you from plugging in something that the circuit can't handle. They shouldn't be giving people 14-50's if they don't have 50A peak and 40A continuous available. (There is a code exception to only allow 40A peak/32A continuous to a 14-50, but that's all most portable EV chargers draw anyway, so I doubt it even met that. And TT-30 offers no such exception at all.)

[–] hnav 1 day ago

Since the whole campground went dark, presumably it was the main breaker. The branch circuit must be sized to the outlet type, but the total rating of all branch circuits usually exceeds the main breaker rating.

[–] josephcsible 1 day ago

That would be a reasonable explanation if most of the campsites had people charging EVs at their max individual current, but it sounded like just one did.