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Posted By: George Little Can't find code reference. Help - 08/16/14 08:27 PM
I seem to remember that in the NEC it said that the grounded conductor (neutral) had to originate from the same panel as the ungrounded conductor. Has that been removed, or am I just wrong? I'm thinking there was an issue with the "Gentran" box used with portable generators. or possibly this 8 circuit panel that includes the transfer switch made by Generac. Thanks in advance.
Posted By: gfretwell Re: Can't find code reference. Help - 08/17/14 12:58 AM
As far as I know, the grounded conductor originates in the service disconnect enclosure where the main bonding jumper lands. Beyond that it just needs to be run in the same cable or raceway as the ungrounded conductors.

Maybe I don't understand the question.
Posted By: George Little Re: Can't find code reference. Help - 08/17/14 01:33 AM
I guess I didn't explain it very well. I'm talking about a situation where we have the ungrounded conductors originating in one panel and the grounded conductors being in another panel like you could end up with using a generator and a transfer switch.

300.3(B) kinda covers it but I was thinking of the situation where the neutrals are coming from a different source.
Posted By: gfretwell Re: Can't find code reference. Help - 08/17/14 02:45 AM
Yup that was where I was going.
Posted By: gfretwell Re: Can't find code reference. Help - 08/17/14 02:48 AM
Where is the neutral coming from and how can they do that without violating 300.3
Posted By: shortcircuit Re: Can't find code reference. Help - 08/17/14 07:03 PM
Wouldn't 300.3(B)(4) be similar in practice to the way a gen-tran transfer switch is installed?

Posted By: shortcircuit Re: Can't find code reference. Help - 08/17/14 07:08 PM
With those gen-tran switches and all the AFCI breakers required...you can't use them and keep the AFCI protection while on generator.
Posted By: gfretwell Re: Can't find code reference. Help - 08/17/14 08:58 PM
Looking at the GenTran installation guide, it does appear that there is a neutral bus in the GenTran and they talk about installing the required GFCI/AFCI breakers in the GenTran.
http://gentran.net/assets/pdfs/EncoreInstall.pdf

I also saw another smaller GenTran that looks like it uses plug fuses. That would be troubling on a new installation. There does not seem to be any provision for xFCI

https://gentran.net/assets/pdfs/oldinstall.pdf
Posted By: shortcircuit Re: Can't find code reference. Help - 08/17/14 09:43 PM
It is the smaller gen-tran switch that is most popular. It is sold in home stores also. This is the one without neutral provisions.
Posted By: gfretwell Re: Can't find code reference. Help - 08/18/14 05:03 AM
The Encore is the one I see listed at my local Home Depot.

If they have one that will not accommodate xFCI breakers and does not have a neutral bus, I would call it a violation, on a couple of counts.
Even if they could make the case that none of the circuits served required GFCI or AFCI, I would still have trouble with the edison base fuse holders, even if they do have push button breakers in them.
(like the second one in my post above)
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