CM type communication wire used in single family house???

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sparks2000

Senior Member
Location
Chicago,IL
Can CM type communication wire used from floor to floor in single family house if it is fire caulked or does it have to be CMR type???
 

sparks2000

Senior Member
Location
Chicago,IL
Has anyone here ever use non-plenum wire in a return air duct, even though your not supose to? Custumer just want to do it like that himself!!! I refused to do the work without CMP!!!
what do you guys do?
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
Has anyone here ever use non-plenum wire in a return air duct, even though your not supose to? Custumer just want to do it like that himself!!! I refused to do the work without CMP!!!
what do you guys do?
You can't install the cable in a return air duct unless it has an outer metal jacket. Just because it is named "plenum" cable does not mean that it is permitted in plenums. There is an exception for dwelling units where the stud or joist spaces are used for return air and the cable is run perpendicular to the space. See 800.154(A) and 300.22.
 

raider1

Senior Member
Staff member
Location
Logan, Utah
code says if its CMP ,it can be used in plenum!!! I dont follow???

Yes it does but it goes on to say that it must be installed in accordance with 300.22 which requires the use of a metal wiring method such as EMT, FMT, IMC and RMC.

Again read 800.154(A) for the use of communications cables in a plenum.

Chris
 

raider1

Senior Member
Staff member
Location
Logan, Utah
i'm talking about a single family house, though!

I understand that, the only leeway that 300.22 has for dwelling units is the exception to 300.22(C) which permits cables to run through joist spaces used as return air where the cables are run perpendicular to the long dimensions of such spaces.

Chris
 

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
Occupation
EC
See Art 300.22 (B) and (C) as well as the exception. A duct or plenum is fabricated (usually sheetmetal) for the distribution or conveyance of environmental air. You would not normally install anything within it unless it was related to the operation of the air handling system such as smoke detectors or possibly work lights in a large plenum.

The space above a dropped acoustical ceiling would be an example of "Other Space used for Environmental Air".

As you can see both have very different requirements.

-Hal
 
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