GFCI sub-panel feed to avoid GFCI circuit breakers in sub-panel?

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DH Electric Co

Electrons, Chess, Bacon & Broads.
Location
Addison, IL
Occupation
Electrician
This may be a stupid question, but honestly I'm still learning all the new codes with these breakers & where required.

40 years experience here, and feel dumber than a cub sometimes with "the times a changin'" ;-)

Also, the NEC isn't what it was when I learned the trade [mid 80's] & I get lost with all the current changes.

So the question:
I have to add a sub-panel to an existing 200 amp residential 40 circuit panel, the panel doesn't allow "minis" or "tandems" for extra branch circuits.
The homeowner also wants TVSS on the service [2 circuits spaces there], plus 3-4 new branch circuits for a home theatre he built.
So a sub-panel is in order.
I will lose 4 full size spaces in main panel, 2 for TVSS & 2 for sub-panel feed.
So 4 branch circuits from the main panel will now be in the sub-panel. + 4 new circuits.

The city doesn't require AFCI, just GFCI on branch circuits below grade [ie: basement finished or not].
So is it legal to GFCI the entire sub-panel with a 240 volt 60 amp or 70 amp breaker to avoid multiple GFCI branch circuit breakers in the panel, or putting in GFCI receptacles all over the theatre for different circuits? One stop shopping so to speak?

And if someone smarter than me could point me to the correct code that cover this?

I'm still tabbing my new code book and feeling old when I go to look something up & can't find it.

Thanks in advance for any help y'all can give me.

Dino
 

Ponchik

Senior Member
Location
CA
Occupation
Electronologist
I can't see any NEC code issues that prevents you from GFCI protecting the whole sub, but for sure not a good idea.

How many circuits do you need GFCI protection on? And what code cyle are you on?
 

DH Electric Co

Electrons, Chess, Bacon & Broads.
Location
Addison, IL
Occupation
Electrician
I can't see any NEC code issues that prevents you from GFCI protecting the whole sub, but for sure not a good idea.

How many circuits do you need GFCI protection on? And what code cyle are you on?
The code cycle is sketchy, changes ever 6 blocks, I'm in the "burbs" outside Chicago. St Charles, IL. The city is on the 2014 NEC, but this is Unincorporated Kane County & the county can't decide where this residence is located, ie: which sub-division & if electric has to be done in conduit or if in romex for one. The sub-division is apparently under a couple of jurisdictions. And there is a homeowners permit which throws me off.

The service & house in is conduit, but know they are saying the home theatre can be done in romex.

The inspector told the homeowner that anything in the basement needs to be GFCI'd, unfinished or finished off basement. [which I don't think the 2014 NEC says, only unfinished basement needs GFCI] So OK, no worries but this is sort of an as-built home theatre as we go. 90% of the wall outlets won't be used currently but due to wall space being finished off they are required, blah blah. It's specifically a movie room.

They are allowing romex, but honestly I'm faster with conduit so that's what I'm installing.

I just don't want to scatter GFCI's all over for what the inspector is requiring, nor pull double #12's & install a bunch of GFCI breakers if I can legally just GFCI the whole sub-panel & call it a day.

I'm not worried about cost, just legally and ease of the job.

Thanks
 

DH Electric Co

Electrons, Chess, Bacon & Broads.
Location
Addison, IL
Occupation
Electrician
I can't see any NEC code issues that prevents you from GFCI protecting the whole sub, but for sure not a good idea.

How many circuits do you need GFCI protection on? And what code cyle are you on?
Sorry, I forgot you asked about circuits, I'm just adding four, plus relocating four from main panel into the sub
 

DH Electric Co

Electrons, Chess, Bacon & Broads.
Location
Addison, IL
Occupation
Electrician
Just an FJY> The homeowner pulled a "homeowners" electrical permit, so I really don't want to call the county inspector with questions, because then they will say "CONTRACTOR" and want to charge me to reciprocate lic and bonding and all kinds of bull.

I was kind of doing this job as a favor.
 
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winnie

Senior Member
Location
Springfield, MA, USA
Occupation
Electric motor research
A 60A GFCI breaker will provide GFCI protection for all connected circuits. GFCI protection can be provided anywhere 'up the food chain' from where it is required.

However it would probably be a bad design decision.

All circuits have some leakage, and the leakage adds up. So a GFCI breaker feeding a subpanel would be at risk of nuisance tripping just from normal leakage current, leakage across things like electronics line filters, etc. It might work, might not.

I would certainly not put any lightning on such a GFCI subpanel.

Jon
 

DH Electric Co

Electrons, Chess, Bacon & Broads.
Location
Addison, IL
Occupation
Electrician
A 60A GFCI breaker will provide GFCI protection for all connected circuits. GFCI protection can be provided anywhere 'up the food chain' from where it is required.

However it would probably be a bad design decision.

All circuits have some leakage, and the leakage adds up. So a GFCI breaker feeding a subpanel would be at risk of nuisance tripping just from normal leakage current, leakage across things like electronics line filters, etc. It might work, might not.

I would certainly not put any lightning on such a GFCI subpanel.

Jon
Thanks for the reply.

I just remember years back installing switch gear and numerous high voltage and low voltage panels in buildings across the country.

And some of them had GFCI protection for the entire panel, and I thought that was industrial & this is resi so why not?

I was just thinking of an easier way to do this, less terminations etc.

Wouldn't a single pole GFCI breaker risk "leakage" on a single branch circuit just like a feeder GFCI breaker to a panel would?

Or even an AFCI single pole breaker risk leakage?
 

DH Electric Co

Electrons, Chess, Bacon & Broads.
Location
Addison, IL
Occupation
Electrician
You had Ground Fault protection that trips at much different levels than a GFCI. Possibly hundreds? of amps vs 5 ma.
Different protection entirely.
thanks,

so I should just toss a few GFCI single pole breakers into the sub-panel and call it a day?
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
The code specifically permits the use of an upstream feeder GFCI breaker to provide the GFCI protection required in 210.8.
(2017)215.9 Ground-Fault Circuit-Interrupter Protection for Personnel.
Feeders supplying 15- and 20-ampere receptacle branch circuits shall be permitted to be protected by a ground-fault circuit interrupter installed in a readily accessible location in lieu of the provisions for such interrupters as specified in 210.8 and 590.6(A).
(2020)215.9 Ground-Fault Circuit-Interrupter Protection for Personnel.
Feeders shall be permitted to be protected by a ground-fault circuit interrupter installed in a readily accessible location in lieu of the provisions for such interrupters as specified in 210.8 and 590.6(A).

However as others have said the cumulative leakage current can cause unnecessary trips.
 

DrSparks

The Everlasting Know-it-all!
Location
Madison, WI, USA
Occupation
Master Electrician and General Contractor
The NEC does not offer a blueprint for making a sound electrical installation. The solution you provide is not sound. For one, an upstream 2 pole breaker protecting an outlet way down stream would be decidedly less responsive than a point of use GFCI. Also, having an entire panel go out during a fault is not only potentially dangerous to life safety, but also would be excruciatingly annoying.

Sent from my BE2028 using Tapatalk
 

DH Electric Co

Electrons, Chess, Bacon & Broads.
Location
Addison, IL
Occupation
Electrician
The NEC does not offer a blueprint for making a sound electrical installation. The solution you provide is not sound. For one, an upstream 2 pole breaker protecting an outlet way down stream would be decidedly less responsive than a point of use GFCI. Also, having an entire panel go out during a fault is not only potentially dangerous to life safety, but also would be excruciatingly annoying.

Sent from my BE2028 using Tapatalk
I agree after I have thought about it. While the solution I asked about may not be sound..........is it illegal? You didn't cite anything I asked for? Can you cite a code violation sir?
 

Ponchik

Senior Member
Location
CA
Occupation
Electronologist
How many circuits do you need that "require" GFCI protection and the GFCI "NEEDSS" to be at the circuit breaker?
 

Jon456

Senior Member
Location
Colorado
In addition to the nuisance tripping and the fact that, if/when it trips, it will shut down the entire panel (which might cause all the lights to go out in the basement if all the basement branch circuits are fed from that subpanel), there's also the consideration of cost.

I'm not sure what type of main panel and subpanel you're working with, but a Square-D QO260GFI costs $185 on the street. Whereas a contractor pack of four GFCI outlets can be bought from a big box store for $50 ($12.50 each) which means you could buy fifteen GFCI outlets for the cost of that single 60A 2-pole GFCI breaker. Will the basement home theater even have that many outlets? And can some of the outlets be daisy-chained downstream from the load terminals of a GFCI outlet?

As for GFCI breakers for the subpanel, a QO115GFI costs $60 on the street. So you could buy three of those for the cost of a QO260GFI. How many of the eight circuits in the subpanel need GFCI protection?

Besides your friend's initial cost, the both of you should consider the cost of maintenance if a device fails. It's much cheaper to replace a failed GFCI outlet than to replace a failed 60A 2-pole GFCI breaker.

Edited to add: I just fully read your second post and see that that cost isn't your primary concern. But from an ease-of-installation point-of-view, I don't see how installing a modern slimline GFCI outlet is any more difficult or time-consuming than installing a regular outlet (unless you're planning to use cheap back-stab outlets, which I never recommend). As for installing up to eight single GFCI breakers in the subpanel, that's only slightly more complicated than installing one GFCI breaker in the main panel, the only difference being the (up to seven) additional neutral pigtails from the GFCI breakers that will have to be landed in the subpanel.
 

winnie

Senior Member
Location
Springfield, MA, USA
Occupation
Electric motor research
I concur.

Perfectly code legal to install a panel with a single GFCI main breaker. But a poor design choice for this installation.

A 'spa panel' is probably the cheapest way to go down this path.

Double check the actual requirements. Must the entirety of the circuits be GFCI protected, or just all outlets, or just receptacle outlets? My preferred installation would be separate receptacle outlet protection.

Jon
 

Ponchik

Senior Member
Location
CA
Occupation
Electronologist
The code specifically permits the use of an upstream feeder GFCI breaker to provide the GFCI protection required in 210.8.

(2017)215.9 Ground-Fault Circuit-Interrupter Protection for Personnel.
Feeders supplying 15- and 20-ampere receptacle branch circuits shall be permitted to be protected by a ground-fault circuit interrupter installed in a readily accessible location in lieu of the provisions for such interrupters as specified in 210.8 and 590.6(A).

However as others have said the cumulative leakage current can cause unnecessary trips.

I will be the devil.

Does this mean that lighting circuits can not be on the feeder? So the feeder has to be specific for a sub panel that only is for receptacle circuits?
 
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