NEC 314.16 B1 box fill

[Jpflex]

To make sure I’m doing this right my metal single gang box measures 4”tall x 2/1/8” wide x 1/3/4” deep but NEC book only has similar box at 1/7/8” deep so I chose this?

Book gives total available volume of 13.0” for above box

Therefore the reason 4 x 12 AWG conductors
4 x 2.25 allowance At 9.0” take up

Plus 4 of 12 AWG ground conductors at 1 x 2.25 allowance at 2.25 take up

Plus 1 yoke receptacle under 2”wide is allowance at 2 x 2.25 take up

Added = 15.25 required allowance for a box labeled 13.0 total allowance is reason I can’t get receptacle and wires to fit



However the book does not mention allowance for internal pigtails such as if I were connecting 2 yokes together through the second receptacle pigtailed to the first receptacle in a two gang box

All the book says is give allowance for wires entering, entering and exiting without splice, if looped beyond minimum 6”? Conductor length from entering box point

What do you measure for pigtails for double gang metal boxes?

 

[Jpflex]

Double gang to be internal pigtail jumped from first receptacle to second receptacle where it is power fed

NEC does not specify allowance for jumpers

 

[Jpflex]

Also in NEC chart what is meant from device vs box for description as I don’t see single gang other than masonry gang?

 

[don_resqcapt19]

To make sure I’m doing this right my metal single gang box measures 4”tall x 2/1/8” wide x 1/3/4” deep but NEC book only has similar box at 1/7/8” deep so I chose this?

Book gives total available volume of 13.0” for above box

Therefore the reason 4 x 12 AWG conductors
4 x 2.25 allowance At 9.0” take up

Plus 4 of 12 AWG ground conductors at 1 x 2.25 allowance at 2.25 take up

Plus 1 yoke receptacle under 2”wide is allowance at 2 x 2.25 take up

Added = 15.25 required allowance for a box labeled 13.0 total allowance is reason I can’t get receptacle and wires to fit



However the book does not mention allowance for internal pigtails such as if I were connecting 2 yokes together through the second receptacle pigtailed to the first receptacle in a two gang box

All the book says is give allowance for wires entering, entering and exiting without splice, if looped beyond minimum 6”? Conductor length from entering box point

What do you measure for pigtails for double gang metal boxes?

314.16(B)(1) .... A conductor, no part of which leaves the box, shall not be counted.

 

[infinity]

Also in NEC chart what is meant from device vs box for description as I don’t see single gang other than masonry gang?

A device box is commonly called a gem box, they come in single gang and can be ganged together to form a multi-gang box. For the square boxes (post #2) the cu in measurement is for the box with a blank cover and without an external mud ring or extension box.

 

[Jpflex]

314.16(B)(1) .... A conductor, no part of which leaves the box, shall not be counted.

A jumper or “pigtail?” Between receptacles, does NOT leave the box nor does it enter or exit the box but is simply made inside the box so I have yet to see what NEC says about the allowance for this as many jumpers can be made within

 

[infinity]

A jumper or “pigtail?” Between receptacles, does NOT leave the box nor does it enter or exit the box but is simply made inside the box so I have yet to see what NEC says about the allowance for this as many jumpers can be made within

Jumpers don't leave the box so they don't count.

 

[Jpflex]

Jumpers don't leave the box so they don't count.

Ok I’ll look into the code again thanks

 

[Little Bill]

You don't count all the grounds (EGC), just one. Well I understand they changed that some, I don't have that code. Even with the change, you don't count all the EGCs.

 

[Jpflex]

You don't count all the grounds (EGC), just one. Well I understand they changed that some, I don't have that code. Even with the change, you don't count all the EGCs.

I only counted grounds once for 4 grounds based on largest conductor and table

 

[Little Bill]

I only counted grounds once for 4 grounds based on largest conductor and table

I see that now but you said "4 grounds" and that's what stuck in my mind.