Another wiring question

[$awdust]

I am running two circuits outside.  One for the pond pump and lights and another for exterior recepticles.  I started running 3 conductor romex from the panel in the pole barn to the box sitting atop the conduit that goes through the slab and outside.

I am putting GFCI breakers in the panel and it came to me that the two circuits will share a common neutral.  Will that work, or do I need seperate neutrals for each circuit to make the GFCI function correctly?

[fredhargis]

Deleted, I'll leave the explanation to the real sparkys.

[Roly]

Don't delete it Fred, you were correct.   Separate neutrals required after the gfci and also they cannot be grounded again after the gfci.   The phase current and neutral current must be the same or it will trip.  Roly

[$awdust]

Thank you both.  That was what I figured, but I was wishing in the one hand but the other hand filled up first. 


I will replace with a couple runs of two conductor.

[srv52761]

But a 240 volt gfci breaker protects both legs??

Switch from the “breakers”   to a single breaker.

He needed to do this anyway if he was sharing the neutral, or tie the handles together.

Wouldn’t this work?

[TDKPE]

You can also run a multiwire circuit (shared neutral) and put a blank face GFCI at each load.  I don't know how far apart the loads are, but wherever they split, or at the two loads after the split, you can use one of these to provide the same protection.  The neutral has to split off with each hot, of course.  About $20 each, and same form factor as any standard device.

[attachment=37790]

[Bob10]

<p>

You can also run a multiwire circuit (shared neutral) and put a blank face GFCI at each load. &nbsp;I don't know how far apart the loads are, but wherever they split, or at the two loads after the split, you can use one of these to provide the same protection.&nbsp; The neutral has to split off with each hot, of course.&nbsp; About $20 each, and same form factor as any standard device.

</p><p><br></p><p><br></p><p><br></p><p>I used those in my kitchen they are in the cabinets and no ugly GFI's above the counter</p>

[fredhargis]

<p>

But a 240 volt gfci breaker protects both legs??

Switch from the “breakers” &nbsp; to a single breaker.

He needed to do this anyway if he was sharing the neutral, or tie the handles together.

Wouldn’t this work?

<br></p><p><br></p><p>Help me out here guys. Does this suggest you can run 2-120V GFCI circuits using a 240V GFCI breaker with 1 neutral? <br></p>

[Roly]

<p>

</p><p> <br></p><p><br></p><p>Help me out here guys. Does this suggest you can run 2-120V GFCI circuits using a 240V GFCI breaker with 1 neutral? <br></p><p>

</p><p>&nbsp;Yes, BUT look at the price for the gfci 240v with neutral&nbsp; breaker.&nbsp; Roly<br></p>

[MstrCarpenter]

Yes, BUT look at the price for the gfci 240v with neutral breaker.

Ok. So a gfic outlet is about $20. A 120v gfic breaker is about $40. A 240v gfic breaker is about $110, but now there's only 3 conductors (plus ground) vs. 4 or 6 for two 120v loads and one 240v load. Question is; in the real world will there be nuisance trips as there are with many arc fault circuits? I'm still learning here too.