Two cable tray questions

[bugzapper]

Two different questions about cable tray in the 2011 NEC:

1. I'm in Alaska and we have some shipboard cable on hand that would be convenient to use for adding a 480v pump circuit into an existing solid bottom cable tray in a shore plant. Would this be considered a nonmetallic-sheathed cable under 334 for the purposes of Table 392.10(A)? Surely if I can run romex (*shudder*), which is what I think of for 334, then I could run a cable designed for a harsh, wet, vibrating environment?

2. Regardless of whether the shipboard cable is allowed, 392.22(A)(3)(b) versus 392.22(A)(6)(b) has me scratching my head. The tray I?m adding to contains multiconductor power and signal cable separated to each side and is 8? wide. 392.22(A)(3)(b) ?any mixture of multiconductor power, lighting, control, and signal cables? gives me 7 square inches of fill to work with from its table. The table for 392.22(A)(6)(b) ?where more than one multiconductor cable is installed? doesn?t even mention an 8? tray, but the average of what?s shown is 45% fill (40, 36, 52, 53). That would be a guesstimate of 3.6 square inches of fill. 7 versus 3.6 is quite a difference. So how do I choose between ?any mixture? and ?more than one?? Doesn?t ?any mixture? strongly suggest by definition there is more than one?

Thanks

 

[petersonra]

I think you missed an important part of 334. NM cables have to be listed as such. If the cable is not listed as NM it can't be used as NM.

I don 't know what kind of shipboard cable you have. If it is not something the NEC allows you can't use it. It might well be listed as something that is usable like TC.

 

[bugzapper]

Thanks Bob, I understand. TC would be 2-3 weeks getting out here and this shipboard cable is sitting here in the flesh (so to speak). This stuff really is designed well for this saltwater environment. I did some more research this afternoon and one of the manufacturers does make it with a TC rating. Too bad the stuff I have doesn't carry that designation, though.

 

[petersonra]

Thanks Bob, I understand. TC would be 2-3 weeks getting out here and this shipboard cable is sitting here in the flesh (so to speak). This stuff really is designed well for this saltwater environment. I did some more research this afternoon and one of the manufacturers does make it with a TC rating. Too bad the stuff I have doesn't carry that designation, though.

You are probably out of luck.