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AKNate avatar image

Common Neutral

I am installing a Multiplus Compact 2000 into a 50 A Airstream travel trailer. I plan to disconnect L1 from the AC circuit panel, run it to the Multiplus, then re-feed the 50 A breaker for that half of the panel with the output of the Multiplus. Here is a diagram of what I want to do.


Is there any problem in jumpering the neutrals like this? The manual shows them separate, but I can't think of a reason it would matter in an RV setup.

Thanks

wiring
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2 Answers
Curt avatar image

What the relay number that would work good for this?

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WKirby avatar image

I would not do this.
There is a double pole relay at AC-IN to disconnect both Live and Neutral when mains is not available. You'd be bypassing the Neutral relay contact with your proposed configuration.

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I realize I would be bypassing the neutral relay, but is there a negative effect from doing so? In an RV application such as mine, the only thing upstream of the Multiplus is the shore power plug. By jumpering the neutrals, I'd be making the neutral pin in the shore power plug "live", but when shore power isn't connected, the Multiplus connects the neutral to chassis ground anyway, so what I would be doing is grounding the neutral pin on the shore power plug.

According to the manual:

If an external AC supply is provided, the ground relay H will open before the input safety relay closes. This ensures the correct operation of an earth leakage circuit breaker that is connected to the output.

So when I plug in shore power, I suppose I would momentarily be creating two potential ground/neutral links - one in the shore power's main panel and one at the Multiplus, before the Multiplus switches. I guess that would be the downside of my plan, depending on how long it takes to switch.

I think I've talked myself out of doing it this way and will have to run another wire.

Thanks for helping me think this through.



"In an RV application such as mine, the only thing upstream of the Multiplus is the shore power plug."

Mis wired connection leads, or shore outlets would be dangerous.


Be safe.

So when I plug in shore power, I suppose I would momentarily be creating two potential ground/neutral links - one in the shore power's main panel and one at the Multiplus, before the Multiplus switches. I guess that would be the downside of my plan, depending on how long it takes to switch.

You've got it, this is the problem. The length of time is irrelevant.
Like klim8skeptic says, please be safe and follow the proper wiring layouts.