Right way to wire a generator tranfser switch?

Aug 11, 2010 14 Replies

Hi Readers,



The installation instructions for the generator transfer switch I want to buy (figure 4 on page 5 of

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that I'm to leave neatly placed wire nuts as connections inside the circuit breaker panel box. My neighbor (with some construction knowledge) says doing so would be an electrical code violation: he says there should be no wire nuts within the panel box. Is it a code violation? If so, what would be the "correct" way?



Thanks for advice, Theodore.


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indicate that I'm to leave neatly placed wire nuts as connections

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Jay

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indicate that I'm to leave neatly placed wire nuts as connections

Your neighbor is absolutely WRONG . A breaker panel is totally acceptable as a junction box. Pigtailing of circuits inside a breaker panel is totally acceptable and very common.

Do it just as it shows in the documentation that comes with the U.L. listed transfer switch, and you will be Nec compliant . and tell your neighbor not to quit his day job

But, but, but... what if his day job is "electrician?"

Thanks, RBM. However, consider the comment "Codes vary in this regard. Some, like ours, allow twist connectors in the main panel, while others may require that you pull all disconnected circuit cables from the main panel and route them into the side panel, via junction boxes." in the website

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) posted in previous reply by Jay Hanig above. Do you have an opinion on this, and on where I would I ask to find out more? Location is New York State.

if that's the case, he's a doofus bastard.

I am not Electrician and in many places have they own code however if any connection is to be done it should be inside some type of electrical enclosure, it could be same panel where switch, Switch-over is located or separate, as long there is enough of room I believe that you neighbored is full of?

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indicate that I'm to leave neatly placed wire nuts as connections

The National Electrical Code allows junctions inside a breaker panel. Some anal retentive jurisdictions may not. I would ask your electrical inspection department in the city or county where you reside.

TDD

Well said, and understood. Thanks, all, for the info!

Thanks, RBM. However, consider the comment "Codes vary in this regard. Some, like ours, allow twist connectors in the main panel, while others may require that you pull all disconnected circuit cables from the main panel and route them into the side panel, via junction boxes." in the website

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) posted in previous reply by Jay Hanig above. Do you have an opinion on this, and on where I would I ask to find out more? Location is New York State.

You have two different types of transfer switches. If I were wiring the one from Green Trust, I would remove the cables from the existing panel, and relocate them into the transfer panel. The Reliance panel you have is not designed to do that. The NEC requires that you follow the instructions that come with the U.L. listed equipment. What you might want to do, is contact whatever electrical inspection authority you have, and just ask if they follow Nec rules regarding generator installations

I agree with verifying what you want to do with the inspector.

The NEC section that allows splicing in a panel, and wires to run through a panel (subject to space limitations) is 312.8.

A while ago John Grabowski posted a link to

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is a relatively cheap and flexible way to do a transfer switch. A circuit breaker (must be "secured in place") in the service panel is connected to the generator. An mechanical interlock on the panel cover prevents both the generator breaker and the service disconnect breaker from being on at the same time. I believe SquareD has a similar interlock for their panels.

Yes, I use the Square D interlock kit on my QO panel and it works well.

When I installed mine here in upstate NY a few years back, the local code office said it was OK as did the inspector who came out to approve it. And that's what you should do; check with your local codes office.

HTH,

Twayne`

Not necessarily compliant to electrical code, though; the only source is codes offices as they have the final say and have the info thr inspectors use. NEC isn't the final word: The code enforcement is the final work. There are also differences in how and whether the external disconnect is positioned; check that too while you're at it.

HTH,

Twayne`

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