Cable Tray Bonding

Status
Not open for further replies.
J

jerryb

Senior Member
Normally cable tray bonding would be based on the size of largerest overcurrent device for the feeder or branch laid into the Tray.
What would be the wire size for cable tray bonding if the tray is used strictly for communication cable? Thanks
 
Re: Cable Tray Bonding

Hi Jerry,

I believe this will answer your question about the size, however, I'm not so so sure it is required to be bonded for grounding purposes.

250.96 Bonding Other Enclosures.
(A) General. Metal raceways, cable trays, cable armor, cable sheath, enclosures, frames, fittings, and other metal non?current-carrying parts that are to serve as grounding conductors, with or without the use of supplementary equipment grounding conductors, shall be effectively bonded where necessary to ensure electrical continuity and the capacity to conduct safely any fault current likely to be imposed on them. Any nonconductive paint, enamel, or similar coating shall be removed at threads, contact points, and contact surfaces or be connected by means of fittings designed so as to make such removal unnecessary.
Click to expand...
 
Re: Cable Tray Bonding

Jerry I can help out here. There are two answers to the question.

One is the NEC minimum requirement, too complicated.

Two is the telecom standard. The cable rack is bonded to every ground bar is passes by with a 2/0 AWG conductor using 2-hole 3/8 inch compression tounge connectors on each end of the conductor. Each cable ladder section will use a # 6AWG bonding conductor with 2-hole 1/4 inch compression connectors. This is common standard practiced by most Telco's.
 
Re: Cable Tray Bonding

Thanks guys for the response. After my original post yesterday I did a little more research on the web and found a copy of the "NEMA Standard for Cable Tray installations". What I found was NEMA #VE 2-2000. In that document they state that if the tray is used for Non-Power applications then the minimum requirement would be a #10 ground conductor.

This seem to be too small. Our standard is to use a #6 copper conductor, but I was trying to confirm or at least understand where this sizing comes from.

Thanks again.
 
Status
Not open for further replies.
Top