Audio Conduit, Box Sizes

[admiralporklung]

Do we have to honor the NEC requirements for sizing a j-box if the conduit (tubing) is for speaker wire?

Thanks a lot.

 

[hbiss]

Depends. The NEC has something to say if it's Class 1 wiring but not CL3 or 2. But I wouldn't even consider that. I always follow the Chapter 3 fill requirements for both the conduit and boxes depending on the wire size when running TFFN or THWN. If you are pulling cables (that will never be Class 1) you need to consult the manufacturer of the cable for the recommended conduit fill. It's usually 40% based in the OD of the cable. But you still size your boxes according to the wire size, number and chapter 1.

-Hal

 

[fmtjfw]

Do we have to honor the NEC requirements for sizing a j-box if the conduit (tubing) is for speaker wire?

Thanks a lot.

See article 640. I can't find fill requirements for junction boxes, but 640.23 requires normal fill for conduit, wireways, gutters, and aux gutters. The wiring also comes under 725 (references in 640 to 725).