50 amp, 240 volt hookup without equipment ground

This is a 50AMP setup that might give you an idea what to look for...


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When measuring the 50AMP Receptacle it should look like this ...

50AMP

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30/20/15AMP

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Most RV's use the 50AMP connections as two zones of 120VAC ONLY.

Only very few high-end RV units actually use the 240VAC connections usually for the Dryer connections...

This is the only way a RV Unit frame gets grounded going through the shore power connection. I would definitely not ever use a connection that did not have the earth ground connection...

Roy Ken

Actually, just attaching the ground terminal to a ground rod won't do much of anything. The ground rod would need to be bonded to the neutral back at the main service panel.
I find it very odd that's it's wired this way. What kind of wire comes to it? Is it an flat SE style cable with 2 insulated wires and then a bare wire with the strands wrapped around the 2 insulated wires?
I wouldn't use it without a ground. It would leave you susceptible to having a hot RV chassis if a wire ever shorts to the frame on your RV.
The GFI solution mentioned would work but a 50A GFI breaker is really expensive.

gfci needs ground also

The only way to safely do that would be using a 50 amp GFI- that would be safe and, I believe, to most codes.

I wouldn't do it without a ground. The ground wire should be there someplace, look close at the wiring where it comes out of the shielding, the ground wire could be there but just cut off when the shielding/insulation around the wires were cut. Another option might be (but don;t quote me) is if the house has copper water pipes and are connected to a metal pipe running outside the house under ground, you might be able to run a wire to this for an independent ground.