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#42232 - 09/17/04 05:18 AM fill factor in a box
tomselectrc Offline

Registered: 03/14/04
Posts: 50
Loc: warren mi us
do'es a gfi plug change the fill factor in a box

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#42233 - 09/17/04 06:18 AM Re: fill factor in a box
Ryan_J Offline

Registered: 08/19/03
Posts: 1355
Loc: West Jordan, Utah, USA
No. Each yoke or strap counts as two conductors, regardless of its physical size.
Ryan Jackson,
Salt Lake City

#42234 - 09/17/04 06:09 PM Re: fill factor in a box
CTwireman Offline

Registered: 02/07/02
Posts: 839
Loc: Connecticut, USA
It is always a wise idea to use a deep box for GFIs, dimmers, etc.

I wonder why the code doesn't address the extra space that GFIs take up??


#42235 - 09/17/04 06:38 PM Re: fill factor in a box
Jacuzzi Guy Electric Offline

Registered: 10/25/02
Posts: 33
Loc: Dearborn Heights Michigan Unit...
If the box is too small. Theres is always the GFI Breaker. No space problems there

#42236 - 09/17/04 11:19 PM Re: fill factor in a box
iwire Offline

Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
GFCI breaker.

Higher cost, more likely to trip from cumulative leakage currents and you have to go find it if it trips.

I will stick with a GFCI outlets in deep boxes at the point of use.

The majority of our prints require GFCI outlets at each location that needs GFCI protection.

Bob Badger
Construction & Maintenance Electrician

#42237 - 09/18/04 08:05 AM Re: fill factor in a box
CJS Offline

Registered: 09/16/04
Posts: 35
Loc: Sanford,NC, USA
Yeah, that's the other thing: GFI's in standard boxes.
It's a good idea to use a larger box but not mandatory. Most of us will learn by experience in this regard because you will often have a ground fault after cramming all of that into the box!

We don't need the NEC to dictate our every move do we? That book keeps getting thicker & thicker as it is...

Anyone who has ever installed a GFI receptacle in a standard sized weather-proof box knows that if you have more than one cable entering the box you will have one helluva time getting that receptacle into the box. And so you add a weather-proof extension ring and you're good to go.
Same with an indoor box: Use a 20.5 cu. in. or even a 22 cu. in. if you have more than one romex to contend with. You'll be glad you do at trim-out.



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