Using backfed breaker as main - NEC?

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cashpoppper

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hvac
While doing an HVAC install, and finishing up, i installed the disconnect and the 240v was still dead. So i asked the homeowner if i could check out the breaker panel, he said sure and was on the way out for the day.

I discovered a proper amp 2pole, turning it on was still nothing, so i pulled the cover and simply found the wires were not hooked up to the breaker, So nothing serious, 2 hots and done. Hvac ran great.

what i thought was a big goofy, is there was the proper generator interlock kit installed, qockg2 going inside a 200amp main service, but service feeds were not going to the main 200amp, some flashlight work and following conduit, there's some 6ga running out to his generator that has a 50amp on the unit itself, and has a 100amp breaker stabbed in thats being feed i'm presuming 100amp service on #3 copper leads?

Technically everything i saw was properly fused, just seemed a bit-kinda weird? I wonder if the box was installed with intentions of dropping proper 3/0 copper for 200amp later with some easy wire moving inside the panel? And the easy band-aid idea to use 100amp feeders with a 200amp breaker was to use the interlock with a 100amp backfed breaker, that needs to be mechanically anchored in place?

I know i cant ask for how-tos, but just a yes/no, is this safe what i stumbled upon and should i bring concern to the homeowner?
 
I hit enter too soon


Essentially the guy has a 200amp panel with the proper interlock kit installed. He's using a 100amp double as a back feed being fed service after the meter. The actual main disconnect 200amp breaker has the 6g THHN wires going out to the generator with the 50amp breakers onboard.

The only reason I can think of doing this bass-ackwards is because he has #3 copper coming from meter and not 3/0.

Its setup completely opposite, technically the wires are current protected correctly, but I wasn't sure if it's safe?
 
The only weird thing i seen as a possible fire hazard was polar is bug connectors on the legs that were used to extend the service lines another 8" to reach the backfeed breaker. I wasn't sure if splices were allowed on service feeders.
 
That is weird. Really weird. But I can't actually point to an NEC violation. The validity of the interlock kit is a UL issue, not NEC. As long as the interlock normally locks out the 200A breaker such that those 6awg can't get fed by the grid, then the 200A breaker is just acting as a disconnect and it's rating doesn't matter.

Personally I would have replaced the 200A main with a 100 or 125 for the utility service and done the interlock more by the book. Arguably the way it was done may violate the instructions for the interlock, which would be an NEC violation, but that depends how those instructions are written. In any case, I can't see how it's unsafe.
 
A couple of possibilities, the original service was 100 amp, but due to Covid, only a 200 amp panel was available, or two, only a 200 amp interlock was available, so panel was changed to 200.
 
I was totally bug eyed and I really had to flashlight his setup. I googled out of curiosity, but I don't think they (squareD, se) offer a smaller breaker for that panel size? I might be wrong and didn't push my curiosity far enough. I don't think its misusing the interlock, its still only allowing one breaker on at a time. And there's stickers (backwards) labeling circuits correctly.

Like I mentioned,I wasn't sure if the Polaris splice extention was NEC permitted on service lines after meter.

Weird but safe. Maybe I'm just overreacting. Thanks for the input.
 
cashpoppper said:
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Like I mentioned,I wasn't sure if the Polaris splice extention was NEC permitted on service lines after meter.

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Click to expand...

Actually there's a relatively new rule that the Polaris (or whatever) have to be listed for use on the line side of the service disconnect. But I bet the installation predates that rule. And in general, no, that's not an NEC violation. The utility might not like it (especially on the *line* side of the meter) but the NEC doesn't care about meters.
 
I did find <125amp breakers for that frame of enclosure. $350-600, his idea backfeed with possible material shortages from covid might of been the cheapest route.
 
cashpoppper said:
I did find <125amp breakers for that frame of enclosure. $350-600, his idea backfeed with possible material shortages from covid might of been the cheapest route.
Click to expand...
Makes sense to me. And I see no problem with the arrangement: you have two interlocked breakers feeding the bus, what does it matter which source goes to which breaker?

Cheers, Wayne
 
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