ECN Forum Forums Code Related Discussion NEC & other Code issues Tray Cable/ IT room floors

2 Questions.

1. 645.5(d), type mc cable can be used in raised floors in IT rooms.

Is this right? I thought it all had to be liquidtight.

Or am I missing the section somewhere that if water lines are under the floor, it all has to be liquidtight.


2. Where do I find where Thhn is cable tray rated? I was at a lumber mill the other day and noticed what I thought was 500mcm in cable tray. Single conductors, not tray cable.

Any help appreciated.


Dnk......

I'm reading in 310.11(B) that conductors such as THHN if suitable for Tray Cable need to be marked TC every 40 inches on the surface of the insulation. There are other marking options for multi conductor cables and all this is spelled out in 310.11.