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Posted By: Grover Shared neutral and 2 GFI circuits - 10/06/08 02:37 AM
Can I run 12/3 across a garage, overhead to a basement, and then use this shared neutral to feed 2 GFI proctected dircuits? Pigtail the neutral to go to each separate circuit - each having 2-3 outlets - unknown and variable loads - depending on homeowner.

Breaker will be a 2 pole 20 - yoked - common trip.

Each GFI will compare incoming - red or black - with neutral, and will be independant of the load on the other red or black feed. Right?

So if the load on the black is 6A and the load on the red is 10A what happens? In this case, does the GFI device look only "downstream", or does it look "upstream" as well - that is, does it see the imbalance at the pigtail, or only on the load side of the device?

Or do I need a 2 pole GFI breaker?

Thanks!

Grov
Posted By: gfretwell Re: Shared neutral and 2 GFI circuits - 10/06/08 04:22 AM
A gfci does not look at anything on the line side of the device. As long as you split out your multiwire before you feed the GFCIs you will be fine
Posted By: wire_twister Re: Shared neutral and 2 GFI circuits - 10/06/08 11:18 AM
2 pole GFCI breaker will not work in that application, stick with the receptacles they will work for you.
Posted By: Grover Re: Shared neutral and 2 GFI circuits - 10/06/08 11:56 AM
Thanks guys!

Grov
Posted By: JBD Re: Shared neutral and 2 GFI circuits - 10/06/08 01:24 PM
Actually, a 2-pole GFCI would work in your case, but there is no need to use one. Your GFCI receptacles idea is just fine.

GFCI's simply look at the total amount of current that flows out of their load terminals and compare it to the total amount that flows back in.
Posted By: Texas_Ranger Re: Shared neutral and 2 GFI circuits - 10/11/08 09:51 AM
After all your 120/240 3 wire feeder is just like what feeds your main panel, so what should be the problem?
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