no because the neutral is required to operate the electronics and trip solenoid in the GFCI. This is the whole basis for the open neutral protection, and why 'normal' GFCIs cant provide the protection, a separate relay is required.
Code violation, Technicality
- Thread starter brother
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no because the neutral is required to operate the electronics and trip solenoid in the GFCI. This is the whole basis for the open neutral protection, and why 'normal' GFCIs cant provide the protection, a separate relay is required.
I still don't get it. If you're getting zapped with 10ma from a faulted hot wire, and that 10ma isn't going back through the GFI, it should see that as a 10ma imbalance, and open the circuit.
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The GFCI can not 'see it' because the GFCIs electronics are 'sleeping' due to the loss of the neutral.
Durrr!
So, now, how does it still turn the power off if it isn't functioning at that point?
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Durrr!
So, now, how does it still turn the power off if it isn't functioning at that point?
I think the proper GFCI uses a normally open relay so if either supply line is lost it opens the circuit. This also means you need to press reset each time you plug the unit in.
I think the proper GFCI uses a normally open relay so if either supply line is lost it opens the circuit. This also means you need to press reset each time you plug the unit in.
the GFCIs with open neutral have a NO relay infront of the GFCI. They come in manual and automatic reset versions.
jaylectricity
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- Massachusetts
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- licensed journeyman electrician
I think the proper GFCI uses a normally open relay so if either supply line is lost it opens the circuit. This also means you need to press reset each time you plug the unit in.
Well sure...if it were proper.
But open a circuit breaker on your SABC. Then close it...do you need to hit the reset button then?
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Well sure...if it were proper.
But open a circuit breaker on your SABC. Then close it...do you need to hit the reset button then?
But that has not been what we have been talking about is it?
jaylectricity
Senior Member
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- Massachusetts
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- licensed journeyman electrician
Well, the first part was a joke. And the second part was slightly off the topic, but I have a plug-in GFI receptacle that doesn't need to be reset. I can't be bothered to go out to the truck right now, but I'll double check it when I get a chance.
there are two different types of portable GFCI. Automatic reset which does not have to be reset every time it is energized, and Manual reset which must be reset every time power is applied.
brother
Senior Member
Ok, now back to our regulary scheduled program....
So this is a code violation, just as I thought. I suppose I will gently let them know about this even though its just a 'technicality'. Why they didn't just hard wire the cord in the box instead of using a twist lock is beyond me.
On the issue of the electronics of the gfci, this is the first I hear of this. I thought the same things as others, that if there was any imbalance in the gfci (even with the neutral disconnected) then it would trip.
So this is a code violation, just as I thought. I suppose I will gently let them know about this even though its just a 'technicality'. Why they didn't just hard wire the cord in the box instead of using a twist lock is beyond me.
On the issue of the electronics of the gfci, this is the first I hear of this. I thought the same things as others, that if there was any imbalance in the gfci (even with the neutral disconnected) then it would trip.
the electronics in the gfci are powered from line to neutral. If the neutral is gone, the electronics in the gfci cant function and it wont sense the imbalance or trip, but the load side hot is still energized...
brother
Senior Member
I'll have to do a little experiment myself.
So are the all the 'new improved' gfcis able to disconnect the power when they lose the neutral on the primary side.I'll have to do a little experiment myself.
its not 'new improved' gfci, its an application specific gfci. there arent any gfci receptacles with open neutral protection.
kwired
Electron manager
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- NE Nebraska
Ok, now back to our regulary scheduled program....
So this is a code violation, just as I thought. I suppose I will gently let them know about this even though its just a 'technicality'. Why they didn't just hard wire the cord in the box instead of using a twist lock is beyond me.
On the issue of the electronics of the gfci, this is the first I hear of this. I thought the same things as others, that if there was any imbalance in the gfci (even with the neutral disconnected) then it would trip.
GFCI breaker or GFCI receptacle on supply side should still be acceptable not certain if hard wiring would be acceptable, most of the time it is not.
brother
Senior Member
Ok, so its UL 943 6.7.2.1c Like this example in the in links.
http://www.reelcraft.com/pdfs/tech_bulletins/GFCI_duplex_box.pdf
Osha requirments
http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=24542
brother
Senior Member
I was refering to the cord pendant. these are allowed and should be hard wired in this instance to an 'approved' UL listed gfci receptacle. This would be code compliant, so long as the gfci in a box is not 'homemade' on the end of th pendant.
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