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#89125 - 09/03/04 01:07 PM Cables in suspended ceiling
Bill39 Offline

Registered: 11/28/01
Posts: 77
Loc: Indianapolis, IN, USA
I'd like some opinions on if this type installation would meet the NEC:

Short version: When can shielded cables be ran in a suspended ceiling and not be in a raceway? Two types of cables, one with 120VDC for small motors and other is 24VDC for sensors, & encoders.

Long version:
Have a large custom control panel (120VAC max) and some test stands w/small DC motors, encoders, and sensors. All are in a lab/testing room. We need to run shielded cables between the control panel and test stands. Conduits (1 for low voltage & 1 for 120VDC) will extend up into a suspended ceiling and end. In the ceiling the cables are to be supported by the metal joists, and ty-rapped together.

2014 / 2011 NEC & Related Books and Study Guides
#89126 - 09/03/04 01:34 PM Re: Cables in suspended ceiling
gfretwell Offline


Registered: 07/20/04
Posts: 9025
Loc: Estero,Fl,usa
Two questions spring to mind, is this a fire rated ceiling and is this a plenum for return air?
Greg Fretwell

#89127 - 09/03/04 01:38 PM Re: Cables in suspended ceiling
iwire Offline

Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
Are these cables a chapter 3 wiring method?
Bob Badger
Construction & Maintenance Electrician

#89128 - 09/04/04 09:20 AM Re: Cables in suspended ceiling
hbiss Offline

Registered: 12/16/03
Posts: 893
Loc: Hawthorne, NY USA
Not so much as would they need to be run in a raceway but what is the required wiring method. I doubt any would have to be run in raceway if the correct wiring is used.

Even with raceway you will have to determine whether these circuits are CL1, 2 or 3 and proceed from there. If any are CL1 you may not be able to use the wire you have even with raceway.



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