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#188580 - 08/18/09 11:00 PM box fill
twh Offline

Registered: 03/11/04
Posts: 895
Loc: Regina, Sask.
A box contains:
a) wires of different sizes (for example #12 which requires 28.7 ml and #8, which requires 45.1 ml), and
b) a couple pairs of wire connectors, and
c) a flush mounted device of less than 2.54 cm,.

The #12 wires are connected to the #8 wires and the device is connected to a circuit with tails of #14 wire, which require 24.6 ml each, but aren't counted because they don't leave the box.

When I deduct the number of wire allowed in the box for wire connectors, can I reduce the number of #12 wires allowed? If the code doesn't specify, it must be my choice.

Can I deduct the #14 wire from the allowable fill, because the device is connected by that size of wire?

2014 / 2011 NEC & Related Books and Study Guides
#188661 - 08/23/09 07:35 AM Re: box fill [Re: twh]
Eddy Current Offline

Registered: 09/26/06
Posts: 112
Loc: Ontario,Canada
Only makes sense that the biggest wire be deducted. You have to use a bigger wire nut on bigger wire which takes up more space in the box.

#188669 - 08/23/09 07:47 PM Re: box fill [Re: Eddy Current]
twh Offline

Registered: 03/11/04
Posts: 895
Loc: Regina, Sask.


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