Plenum cable INSIDE ducts?

[brannen]

Reading section 800 of the code for Communication cables - they reference putting plenum cable inside ductwork.

Is this a normal practice? Is in considered acceptable or good workmanship by Electricians and/or Air Conditioning people?

 

[brannen]

Re: Plenum cable INSIDE ducts?

However 820.3(A) refers back to 300.22(B) Ducts or Plenum Used for Environmental Air Only MI, MC, EMT, IMT, IMC, or RMC ... shall be installed in ducts or plenums specifically fabricated to transport environmental air.

This seems to indicate if it's a duct, designed for Air Conditioning, then you just can't throw some plenum rated cable in the duct to get it down to the first floor ...

 

[ryan_618]

Re: Plenum cable INSIDE ducts?

You can't put anything in the duct, regardless of wiring method, unless it is required to be in the duct for the purposes of controlling the air in the plenum. If you are required to have wiring in the plenum becasue it is controlling the air (or acting upon it) then you must have one of the wiring methods listed in 300.22(B)