15/30/50 SHORE POWER PLUG IN ?

fj12ryder wrote:
So if someone wired up an RV outlet the same as a welder outlet, and plugged a 50 amp RV plug into it, what would happen? Nothing?

I know I've read about people plugging into an outlet at someone's house and frying their electrics due to running 240 Volts to their 120 appliances. Would that just be a result of the outlet being wired incorrectly, and have nothing to do with the wirer copying a welder outlet?

Am I laboring under a misapprehension here? I know that I lost one leg of my 50 amp service and then had some appliances, lights, and outlets not work.

Plugging a 50A RV into a 240V welder plug is just a problematic as plugging a 30A RV into one. It's also the same as if you have an open neutral due to a poor connection to a legitimate 120/240 RV pedestal.

What happens is all of the 120V loads on one leg in your RV are now effectively wired in series with all of the loads on the other leg. If both legs drew the same amount of power, they would stay at 120V each. However the reality is that the heavier loads will pull their floating neutral up toward their leg which makes their voltage much lower than 120V and the opposite leg rises by the same amount to something higher than 120V. Worst case you can approach nearly 0V on one side and 240V on the other. This is why an EMS should be used on 50A RV's in my opinion.

Some reading here: https://www.electriciantalk.com/f2/theory-open-neutral-36386/