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Posted By: Niko generator transfer switch - 09/22/11 01:18 AM
I am planning on installing a manual transfer switch (200A) for a standby residential generator. The transfer switch will be immediately after the main 200Amp disconnect. My question is do i need to have a fused or non-fused transfer switch. Please provide NEC reference so i will learn and know for future.

Thanks for the replies
Posted By: sparkyinak Re: generator transfer switch - 09/22/11 02:58 PM
It will have alot to do with which code revision you are under and local code. I'm out of the office and way from me code books as long as you wire the switch as a 200 and switch all the way through you generator panel then I don't see a need for additional OCPD's. It's protected.

A little side note with my inspector cap on, its my humble opinion even though it sounds like you are just doing an add on, it has to meet current code. I do belive in the 2008 cycle requires an automatic switch, not manual
Posted By: Niko Re: generator transfer switch - 09/22/11 03:24 PM
We are under the 2008 NEC and it seems Manual switch is allowed. The main service is 200Amps but the portable generator is rated at 50Amps. I am installing 200Amp switch for future capability.
Posted By: KJay Re: generator transfer switch - 09/22/11 09:46 PM
If it’s a 200A transfer switch on the load side of the 200A service disconnecting means, I don’t see why it would need to be fused, especially if its service rated and sized for the full load.
I don’t see anything the NEC that would require it either and I have never been required to install a fused transfer switch on a residence before. The generators I’ve installed all had their own built in OCP, which was rated lower than the maximum rating of the transfer switch.
Posted By: HotLine1 Re: generator transfer switch - 09/22/11 09:48 PM
Niko:

Ditto to what Kjay said above. OCP before xfr switch & full rated & service rated...no issues.

Posted By: Niko Re: generator transfer switch - 09/22/11 11:25 PM
I appreciate your replies.

Learning never exhausts the mind.
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