Neutral Ground Bonding in an RV

[cpeters]

I am sorry if you guys are sick to death of this topic, and I did try to read previous posts on this topic but I am still very much confused. I have recently been involved in some debate on this issue, and people seem to be quoting different NEC sections to support their viewpoint. It also seems that in 2005 some revisions may have been made which change the outcome of the discussion.

I was under the assumption that Neutral and Ground should be bonded in only 1 place, and that place is the source of power. However, most RV's can have three power sources, 1) Shore Power, 2) Genset Power and 3) Inverter Power. (How you switch between them is not at issue here yet.)

1) Shore Power. With out a doubt it is agreed that when connected to shore power, neutral/ground is bonded at the shore panel, not inside the RV. You are in effect a sub panel. Your breaker panel in the RV has isolated neutral and ground.

2) Genset Power. I used to think this was clear cut, but recent discussion has clouded the issue. For simplicity sake, suppose the shore cord (4 conductor L1-L2-N-G) is unplugged from the shore power and plugged into the genset. Some contend that in this case you should not bond neutral and ground, and others contend you must. They fire NEC sections at each other and then start saying that in 2005 things changed or were clarified.

3) Let's not even go here. Whew.

So, let's focus on number 2 if we can. Can anyone say with certainty which way it should be? It sure would be nice if I could refer people to certain text which would support one method over the other. This seems to be a very passionate issue that keeps coming up over and over again.

Thanks for your time,

Chris Peters
RTS-Bus-Nuts Moderator

 

[jagster]

I'm not sure if this helps, but in the ieee book 6.4.111 states that the nec requires bonding at the main service panel and at the secondary side of a seperately derived system This I believe would pertain to a generator regardless of location. Hopefully a moderator or an engineer type will add more or tell us differently. Joe

 

[rcarroll]

If I give you code sections, Will that help? '05 NEC 250.34(C). If I read that right, the bond will be at the generator frame. I admit, I have never inspected an RV. & until today, never read thru the RV chapter. Welcome to the forum & good luck. Ron

 

[LarryFine]

Chris, it appears that, since the shore-power connection has the bond at the service, and your cord has separate neutral and grounding conductors, the generator must be set up the same way, so the cord sees both sources with the bond in place.

 

[iwire]

I agree with the others.

No bond in the RV panel.

Bond at the utility supply.

Bond at the generator.

The RV will only be connected to one bonded supply at a time.