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Posted By: sparkync generator panels - 02/04/04 09:15 PM
I'm thinking about putting a 16 circuit,100amp Square D panel beside the 200 amp. main panel, and feeding this with a 100 amp. wire and breaker. There will be probably a 30 amp. main for the generator. The panel will have one of the Square D interlocking clips for the Main Breaker and the Generator main breaker. There will be a 4 wire male recpt. for the Generator hook up. I will then pull the circuits the homeowner wants into the panel. I'm not sure what size generator he
has, but he could then pick the circuits that he wants to use during an emergency. Is there anything in the code you know of that prohibits the amount of load I can put in this panel. Does it have to be sized with the generator, or can it be up to the homeowner to decide which loads he wants. Of course the other requirements will be met as to wire size of feeders... etc...
I know there are generator panels out there that are already sized, for instance 6 cir. etc. but then you are limited to what you can put in it. And I know that there is the chance of overloading the generator,But the homeowner could monitor this, either by computing the load he is using, or by installing watt meters. Is this a code violation, or just a safety precaution for the generator owner?
I'll be looking myself in the code to see if I can find it... Thanks for the help.. Steve

ps. I understand that it may cost more the way I want to do it, but it will give more options on the circuits that can be used..
Posted By: sparkync Re: generator panels - 02/05/04 07:54 PM
Just to let you know, I got in touch with our inspector about my question. I think we've went over it before. What I was going to do was alright, but he informed me that
the neutral had to be able to be opened if the generator wasn't "solidly grounded". Also that most portable generators are not solidly grounded. This means that most of the generator panels that are on the market are essentially illegal with portable generators, at least in my area, unless you have a transfer switch that breaks the neutral also [Linked Image] Looks like the generator manufacturers would take that in consideration when they manufactured their generators if possible.. Steve.....
Posted By: sparkync Re: generator panels - 02/05/04 10:02 PM
Talked to my inspector again. He told me if the neutral and ground are bonded in the generator, then I don't have to switch the neutral. I went back and read some of the discussions in the archives here on the forum. Is this not contrary to some of the comments stated here, or did I misunderstand?
Also looks like the generator manufacturers would be made aware of this problem and make provisions for their generators to be used either way.. as a portable unit to be used by themselves, or as an emergency unit to be used as a back up system [Linked Image] Does not UL
labs. or someone regulate these kind of circumstances? Just wondering and trying to get it straight. Thanks for any input.. I know we have went over some of these same things before, but it seems that it still hasn't been settled somewhere. Since the need for the use of back up power is greater these days, and some people cannot afford the $ 700.00+ dollars extra for a transfer
switch that switches the neutral, looks like something could be done.. Well just letting off some steam [Linked Image] Seems like there should be a better way. If the manufactures don't remedy the situation, it will just be done contrary to code by most who don't get it inspected..... All for now... Thanks for listening..
Posted By: russ m Re: generator panels - 02/05/04 10:44 PM
I in believe if you have the grounded conductor bonded at both the service and the generator, that it requires you to break the neutral with a four pole transfer switch.

While the neutral is conducting current, with both systems bonded, you will allways have some current flowing on the equipment ground between the two. That is unless you break the circle by opening the neutral.

[This message has been edited by russ m (edited 02-05-2004).]
Posted By: Wirenuttt Re: generator panels - 02/25/04 03:11 AM
SparkyNC;
Sounds like your customer already has a generator. Just to let you know, Cutler-Hammer has a great one for a great price. It's a 10KW generator in an outdoor enclosure with limited sound supression. Comes with an automatic 200 amp panel transfer switch. It runs on natural or propane. It has a weekly auto start to prevent rust and maintain fluids and reliablilty. It's cost is around $4K or less.
Posted By: Reel-Break Re: generator panels - 03/01/04 06:02 PM
I recently installed a generac system comes with xfer switch and panel.Intructions never mentioned opening the neutral I don`t think it did.Does any one else know about this? It comes with cables to panel outdoor splice box and all even the propane fittings.Could it be they over looked a potential safety hazzard?I`d like to here back if there`s a problem or a potential problem.. Thanks I`ve also done exactly what sparky is refering to.Is solidly grounded meaning bonded with ground wire and 8` ground rod.Thats what I did.
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