Standby Generator on a sub panel

[rayseeger]

I have a customer that bought a "condo", basically its like a commercial office complex, single story, kinda shaped like a horse shoe, he purchased an end unit. There is a large 3phase 120/208 service to the structure with a tap box and service disconnects at the meters. He has a 200 amp 3 phase panel(sub panel) in his space. He wants a small standby generator(10kw single phase) to handle a few lights and receptacles. I proposed to the inspector setting an automatic transfer switch and a sub panel, grabbing a few 120 volt circuits and putting them in the generator panel. Inspector says he wont allow this, says how is it going to prevent a backfeed to the other structures, how it the fire department going to know there is a seperate source of power. i said with the required signage on the meter base( and you can see the generator location from the meter), and the transfer switch is constructed so it cannot be closed to both at the same time.
He is the senior electrical inspector.

 

[augie47]

Senior or not, he seems to have his head in the sand.

 

[hillbilly1]

I can see having disconnecting means for the Fire Department grouped together with the other mains, but he is way off base on the backfeed issue.

 

[rayseeger]

I really dont think he's got the picture of what i"m proposing, the whole reason i called was to make sure he wasnt going to give me a problem for some reason with it being single phase and the service is 3 phase or with it basically being a residential standby in a commercial application. Then he comes out with " I wont allow that". I'm going to call back and see if he wont meet me out there to take a look at it. Is he just being unreasonable or what. I'd hate to go over his head, I really dont like to do that. What do you think?

 

[ceb58]

I really dont think he's got the picture of what i"m proposing, the whole reason i called was to make sure he wasnt going to give me a problem for some reason with it being single phase and the service is 3 phase or with it basically being a residential standby in a commercial application. Then he comes out with " I wont allow that". I'm going to call back and see if he wont meet me out there to take a look at it. Is he just being unreasonable or what. I'd hate to go over his head, I really dont like to do that. What do you think?

The easy solution would be to use one of the ATS's that have 8 circuit. built in. Feed the ATS from his sub panel and put the lighting loads in the ATS. With the signage at the utility disconnects and a generator disconnect that meets 225.32 you are good to go.

 

[Speshulk]

I have a customer that bought a "condo", basically its like a commercial office complex, single story, kinda shaped like a horse shoe, he purchased an end unit. There is a large 3phase 120/208 service to the structure with a tap box and service disconnects at the meters. He has a 200 amp 3 phase panel(sub panel) in his space. He wants a small standby generator(10kw single phase) to handle a few lights and receptacles. I proposed to the inspector setting an automatic transfer switch and a sub panel, grabbing a few 120 volt circuits and putting them in the generator panel. Inspector says he wont allow this, says how is it going to prevent a backfeed to the other structures, how it the fire department going to know there is a seperate source of power. i said with the required signage on the meter base( and you can see the generator location from the meter), and the transfer switch is constructed so it cannot be closed to both at the same time.
He is the senior electrical inspector.

You gotta love someone that's an "inspector" but doesn't understand the concept of a transfer switch.

 

[rayseeger]

Finally spoke with the inspector after him not returning any calls, says he spoke to 3 other inspectors and he is citing 702.6 in the 2008 NEC. You cannot put a 1 phase generator and transfer switch on a 3 phase system. I dont see how that article applies at all. Can anyone please help me see what he's seeing in that article?

 

[augie47]

I do not see what he is seeing either

 

[qcroanoke]

Finally spoke with the inspector after him not returning any calls, says he spoke to 3 other inspectors and he is citing 702.6 in the 2008 NEC. You cannot put a 1 phase generator and transfer switch on a 3 phase system. I dont see how that article applies at all. Can anyone please help me see what he's seeing in that article?

It's not in there. He does not understand what you are doing and he is not willing to understand it either.
You will probably have to go over his head.