3x2x1-1/2” handy box with 14/3.

[jar546]

I had an installation today where they brought MC cable, 14/3 into an inch and a half handy box. It is supposed to have a switch in it. Is this code compliant for box fill?

can you think of any scenario where an inch and a half deep handy box would be code compliant for box fill?

 

[fatboy]

Don't have an NEC in front of me, but I am reasonably sure that is not compliant, but maybe that is a plug recept not allowed.

 

[Paul Sweet]

According to Appleton's table a 3" x 2" x 1 1/2" handy box is only 7.5 cubic inches.
https://www.ideadigitalcontent.com/files/11301/AEC_MC007_Switch_and_Outlet_Boxes_and_Covers.pdf

Two conductors + clamp(s) + a device (double allowance) + grounding conductors = 6 x 2 = 12 cubic inches required.

 

[jar546]

OK so this is not compliant. A 2x3x1-1/2" handy box can't be used for any receptacle or switch no matter what the wire size. Maybe as a fixture box for a sconce.

 

[jar546]

Let me expand since we know that a 3x2x1-1/2" "handybox" cannot be used with any devices using 12 or 14 awg wire.

NEC Table 314.16(A) shows us that the box has a capacity of 7.5 cu/in.

The maximum number of conductors on the chart are: 14awg -3 and 12awg -3. This means that the ground, one white and one black and you are done. If you attempt to add a switch or receptacle, you are now over. If you run 14/3 wire you are over before you even think about a device. The box can only be used on the end of a circuit because you can't even come in with one 14/2 and leave to another box with 14/2. Basically they are good for fixtures where no devices will be in the box.

 

[Builder Bob]

unless it is a light fixture and the canopy cover provides the required capacity for the wiring - far fetched but don't always eliminate the abstract.