Cable Tray

[highkvoltage]

We were having a discussion today about cable tray and a coworker claimed that an inspector turned him down on a job for having to many 90 degree bends in a run of cable tray. He stated that cable tray is a raceway, which I agree with, and is limited to 360 degree in total bends, which I disagree with. The code does not state any such requirement for cable tray. Any input would be appreciated.

 

[tom baker]

Re: Cable Tray

Cable tray is not a raceway. Its a support system. In the cable tray you can run AC cable, NM cable, tc...
Here is what the NEC says:
392.2 Definition.
Cable Tray System. A unit or assembly of units or sections and associated fittings forming a structural system used to securely fasten or support cables and raceways.
The AHJ must cite a code section restricting the cable tray to 360 degrees, now perhaps if LTNMC was run in the tray, the LTNMC would be limited to 360 degrees, but not the tray.

 

[rbalex]

Re: Cable Tray

Tom gave the definition of a "cable tray system;" its also worth looking at the definition of "raceway."

Raceway. An enclosed channel of metal or nonmetallic materials designed expressly for holding wires, cables, or busbars, with additional functions as permitted in this Code. Raceways include, but are not limited to, rigid metal conduit, rigid nonmetallic conduit, intermediate metal conduit, liquidtight flexible conduit, flexible metallic tubing, flexible metal conduit, electrical nonmetallic tubing, electrical metallic tubing, underfloor raceways, cellular concrete floor raceways, cellular metal floor raceways, surface raceways, wireways, and busways.

It's a pretty exhaustive list - and "cable tray" isn't on it.

The 360 rule is NOT general. That is why it is specifically listed in each of the 10 raceway Articles where it applies.

[Edit Add:] BTW, for our neighbors to the north, the Canadian Electrical Code does consider cable tray a raceway, because it may be used as an EGC.

[ September 23, 2004, 08:05 PM: Message edited by: rbalex ]

 

[highkvoltage]

Re: Cable Tray

Thank you both. Mr. Baker possible may have found the true violation and I will ask what type of conductors they were installing. This is why I love the forum. I read it almost every day.