ATS neutral (grounded Conductor)

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myjemi

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I’m told by several generator installers that when installing a Generac 200a 1P ATS off a single 200a meter combo on a single family dwelling that you can’t just install your feeder wires, 2 hots and 1 neutral, off the load side of the first means of disconnect and land them to the utility side of the ATS and bonded neutral bus and only run the 2 hot feeders back to the meter combo tapping the feeders that go to the panel.

They say I must run a neutral from the ATS back to the meter combo where I’m tapping the original feeders.

I can’t find any code that supports this. I’ve never been failed by an inspector for doing this. Any code help?
 
Meter combos pose a problem with generators, especially on existing services. The only thing you can do is feed the ATS with 4 wires, remove the bond in the service rated ATS, then another 4 wires to the house panel. You can't change the neutral bond in the meter/main so anything leaving there has to be a 4-wire.
 
I agree. A better choice would be to use a non service rated switch in this case. But if the SUSE rated switch is all you have or can get, well, that works too. Just sort of redundant and wasteful.
 
Assuming the the ATS doesn't switch the neutral then I think you can run one neutral and four hots. We debated this recently here.

That said, I wouldn't be surprised if the Generac guys are saying that because some inspectors made them do it. I have met those inspectors buddies and been driven nuts by them.

(If the ATS switches the neutral then I hope it's obvious you need to bring both utility and load neutrals to it.)

As others have said, if you have a meter main combo then the ATS can't have an MBJ.

I think there is no usually no legal way to back up distribution in a meter main combo. It's arguably a disallowed modification of listed equipment, a violation of wire bending space, or both. Might be some exceptions out there with enough space and proper existing lugs, but not in any 200A panels I've seen of recent manufacture. You either move the loads you want backed up to a different panel or replace the meter main for a proper install.
 
myjemi said:
I’m told by several generator installers that when installing a Generac 200a 1P ATS off a single 200a meter combo on a single family dwelling that you can’t just install your feeder wires, 2 hots and 1 neutral, off the load side of the first means of disconnect and land them to the utility side of the ATS and bonded neutral bus and only run the 2 hot feeders back to the meter combo tapping the feeders that go to the panel.

They say I must run a neutral from the ATS back to the meter combo where I’m tapping the original feeders.

I can’t find any code that supports this. I’ve never been failed by an inspector for doing this. Any code help?
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You can't have the neutral bonded at the transfer switch after the first means of disconnect, but I don't see any reason to bring a neutral back out of the transfer switch.
 
An item of interest for people in Northern California (PG&E service area) who want to add a small generator to a meter/main installation is this new program that offers a Smart Meter with collar, containing a 30A/240V inlet receptacle and an ATS. The generator would be manually started, since there is no generator control provision in the meter.
I do not know whether or not the ATS switches the neutral too, but it seems like the best design choice to accomodate all portable generators.
 
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