Up to 4 #14 or smaller fixture wires aren't counted in box fill anyway, so a box that is properly sized for the branch circuit conductors is sufficient. See 314.16 (B)(1) Exception.
410.10 Space for Conductors Canopies and oulet boxes taken together shall provide adequate space so that luminaire (fixture) conductors and their connecting devices can be properly installed. The italics are mine.
Re: Wires in canopy?#87501 03/14/0403:15 PM03/14/0403:15 PM
Thanks for your insight. I guess I'll will take a different view of this subject thanks for the code reference. I still am kinda nervous about allowing someone to install a 3" pan box with two 14/2 w/g for connection of a luminaire. I think I'll ask him for some specs on the proposed fixture, I'm sorry, luminaire.
Re: Wires in canopy?#87502 03/14/0404:27 PM03/14/0404:27 PM
The exception that Scott (electure) posted above applies to the fixture wires not the branch circuit conductors. Using a 3/0 pancake box with even one 14-2 NM cable is a violation unless the box is extended with an extension ring or canopy that is marked with its cubic inch capacity. I have never seen a fixture canopy that has been marked with its capacity. A single 14-2 NM cable would require a minimum of 6 cubic inches if an external clamp is used or 8 cubic inches if an internal clamp is used. A 3/0 pancake has a 4 cubic inch capacity. Two 14-2 NM cables would require 10 cubic inches with internal clamps or 12 cubic inches with internal clamps.
Re: Wires in canopy?#87503 03/14/0410:17 PM03/14/0410:17 PM
When I inspect I allow (1) 14-2 NM cable in a 3-0 pancake box. I realize that it is not permitted, but I also realize that sometimes that is the only way you can go about the installation. I will not, however, allow (2) 14-2's or (1) 12-2.
Ryan Jackson, Salt Lake City
Re: Wires in canopy?#87504 03/23/0409:01 PM03/23/0409:01 PM