GFCI Protecting Entire Pool Panelboard then use standard breakers?

kwired

Electron manager
Location
NE Nebraska
Thanks for the help guys! I understand and agree with everyone who has an issue with narrowing down any ground fault issues when the whole panel is gfci protected. Its all about what is available. I can't even get square D stuff here right now. It makes sense to gfci protect the whole panel for all the 240v stuff and then add 120v branch cicircuit gfci breakers where required at this point.
those 120 volt circuits would already have GFCI protection via the feeder GFCI just like the 240 volt circuits
 

mbrooke

Batteries Not Included
Location
United States
Occupation
Electricity
(y), I guess.
Although it would require a simultaneous double fault in two different locations to both generate a voltage gradient and not trip the feeder GFCI when the first fault occurs. A single line to neutral fault where the two insulation breakdowns are far enough apart to generate a voltage gradient is almost certain to pass enough EGC/equipotential grid current to trip a feeder GFCI.

Is that not why bonding comes in? To bring everything to the same potential if the GFCI failed and EGC did not open an OCPD?
 

rnatalie

Senior Member
Location
Catawba, NC
Occupation
Retired Electrical Engineer
Is that not why bonding comes in? To bring everything to the same potential if the GFCI failed and EGC did not open an OCPD?
Bonding only covers the things so bonded. If the bonding was absolute, we'd not lose people due to pool lighting.

I'll agree that you have to have a double (or sometimes triple failure) for this to be a problem, but such has happened. I'm sticking to putting a GFCI on each branch circuit whether it's strictly required or not.
 

mbrooke

Batteries Not Included
Location
United States
Occupation
Electricity
Bonding only covers the things so bonded. If the bonding was absolute, we'd not lose people due to pool lighting.

I'll agree that you have to have a double (or sometimes triple failure) for this to be a problem, but such has happened. I'm sticking to putting a GFCI on each branch circuit whether it's strictly required or not.
Before code mandated GFCIs bonding is what kept pools electrically "cold"
 

TheGingerElectrician

Master Electrician Electrical Contractor, TN
Location
Tennessee
Occupation
Electrical Contractor
My bigger concern when it comes to undesired tripping and GFCI protection of a feeder instead of individual branch circuits is the accumulation of leakage that would be allowed on an individual circuit to build up to enough leakage on the feeder to trip the feeder GFCI.

Say you have 6 circuits and each one has capacitive leakage of 1 mA. With GFCI on individual circuits none of them trip. With a GFCI on the feeder, you are at the trip threshold. When you come to troubleshoot you will likely examine each circuit individually to determine which one has the fault but you don't find any individual circuit that is causing problems, then when you put everything back to normal you back to being right near the trip threshold again.

I think by installing this way you possibly setting yourself up for callbacks that may be difficult to find the problems.
I 100% agree with you but I'm out of options at this point and either shut down because we don't have what I'd prefer or we find a way to make it work and still meet the minimum in safety standards. It sounds like others have had good success with this so far. I don't like it by any stretch of the imagination... Once more breakers are available again we can always address that if it becomes an issue later but at least I've got a way for the customer to use their new $80,0000 dollar pool, pass inspection, and sleep well knowing we aren't going to kill anybody.
 

kwired

Electron manager
Location
NE Nebraska
Before code mandated GFCIs bonding is what kept pools electrically "cold"
Yes, that primarily for keeping all objects in and around the pool at same potential. Introduce an ungrounded conductor into the pool area and you could still have a voltage gradient in its vicinity, but any leakage current would still cause the GFCI to trip and eliminate the hazard. Granted the light should be bonded and this should be pretty rare issue, but the light is about the only thing typically in the pool where you might find actual line volts being present in normal operation. Pumps and other similar items are in contact with pool water but often not where pool users are going to contact them.
 

mbrooke

Batteries Not Included
Location
United States
Occupation
Electricity
Yes, that primarily for keeping all objects in and around the pool at same potential. Introduce an ungrounded conductor into the pool area and you could still have a voltage gradient in its vicinity, but any leakage current would still cause the GFCI to trip and eliminate the hazard. Granted the light should be bonded and this should be pretty rare issue, but the light is about the only thing typically in the pool where you might find actual line volts being present in normal operation. Pumps and other similar items are in contact with pool water but often not where pool users are going to contact them.

Agree, but as I see it a GFCI is nothing more than a backup to bonding and EGCs.
 

brantmacga

Señor Member
Location
Georgia
Occupation
Electrical Monke
It would already be GFCI protected by his "pool panel" that has GFCI on it's feeder though. Unless he feeding lights from a different feeder, but why do that?
Because it’s a code requirement in 680; lighting must have gfci within the branch circuit.


Sent from my iPhone using Tapatalk
 

kwired

Electron manager
Location
NE Nebraska
Agree, but as I see it a GFCI is nothing more than a backup to bonding and EGCs.
Equipotential bonding isn't about fault clearing, it is about equalizing potential. Bigger concerns are over potential possibilities that a GFCI can not detect, like a grounded service conductor with voltage drop on it- even if only a couple volts drop it will impose that couple volts on all EGC's and everything bonded to the EGC whether intentionally or incidental. That leaves that voltage exposed to pool users if they get between bonded objects and true earth potential. By bonding everything in the pool area together you must be out past the perimeter of said bonding before you can be subject to that voltage gradient, presuming you didn't miss something and leave a hole in the equipotential bonding system.
 
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