Forum Discussion
CA_Traveler
Sep 18, 2013Explorer III
Let’s try this approach. You run a circuit from a neighbor’s house into your house. Do you connect the grounds of the two houses or not? Doubtful that there is any building code for connecting/not connecting the grounds but unlikely the code allows the second circuit.
So if we’re in violation of some building code which doesn’t apply to RVs what are the considerations for adding a second circuit?
Connecting the grounds means that you have a parallel circuit and should for some reason the ground is carrying a lot of current there could be more current on the 20A ground then the wiring supports. Not likely but under the right fault conditions…
If the grounds are not connected then there will be a small voltage potential between the grounds and under the right fault condition it could be larger. So someone touching both grounds perhaps through 2 appliances could get shocked. Again this is not likely…
If the grounds are not connected and the main cord is not plugged then it’s like you have an extension cord running inside. But under the right conditions you could have a leak to the frame which is not grounded. Again this is not likely… And if the second extension is plugged into a GFI it would trip with a ground fault.
I don’t see a right or wrong way for connecting the grounds given that bringing in the second circuit is “wrong”.
My second circuit is not grounded to the frame except when it’s plugged into the outside plug. And even then it’s a male/female plug connection and not a bonded ground.
It’s doubtful that I’ll bond the second circuit ground to the frame. In fact when I sell the rig I’ll fully disclose the circuit or better yet just remove it.
That said we had a lot of 30A sites this summer (Alaska trip) and that extra 20A for ceramic heaters was very nice.
Running the ceramic heaters was for me the main consideration as I don’t like to run anything that generates carbon monoxide while sleeping like HW or furnace. But I’m a risk taker and leave the refer on propane while boon docking! :B
So if we’re in violation of some building code which doesn’t apply to RVs what are the considerations for adding a second circuit?
Connecting the grounds means that you have a parallel circuit and should for some reason the ground is carrying a lot of current there could be more current on the 20A ground then the wiring supports. Not likely but under the right fault conditions…
If the grounds are not connected then there will be a small voltage potential between the grounds and under the right fault condition it could be larger. So someone touching both grounds perhaps through 2 appliances could get shocked. Again this is not likely…
If the grounds are not connected and the main cord is not plugged then it’s like you have an extension cord running inside. But under the right conditions you could have a leak to the frame which is not grounded. Again this is not likely… And if the second extension is plugged into a GFI it would trip with a ground fault.
I don’t see a right or wrong way for connecting the grounds given that bringing in the second circuit is “wrong”.
My second circuit is not grounded to the frame except when it’s plugged into the outside plug. And even then it’s a male/female plug connection and not a bonded ground.
It’s doubtful that I’ll bond the second circuit ground to the frame. In fact when I sell the rig I’ll fully disclose the circuit or better yet just remove it.
That said we had a lot of 30A sites this summer (Alaska trip) and that extra 20A for ceramic heaters was very nice.
Running the ceramic heaters was for me the main consideration as I don’t like to run anything that generates carbon monoxide while sleeping like HW or furnace. But I’m a risk taker and leave the refer on propane while boon docking! :B
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