Control Wire in conduit

Status
Not open for further replies.
OK NEC I am reading 800.110 (2) (B) raceway fill does not apply to control wires so what I can run as many as I can fit in a 3/4 in. EMT without breaking code? Seems to me something wrong with that....

Thanks for the input
 

fmtjfw

Senior Member
725? class 2 or 3?

725? class 2 or 3?

These control wires are not article 800, they are article 725. Article 725 installations inherit chapters 1 through 4, unless 725 indicates an exception. The words "raceway fill" are not found in 725, so you use the standard raceway fill calculations. No raceway fill calculations are above 60% I believe. 40% probably applies in your case.
 

iwire

Moderator
Staff member
Location
Massachusetts
I beleive so I have A/C control wires 24v running from my roof top units and from my VAV's to the control cabinet down in the equipment room. They are in 3/4 EMT at about 85 to 90 percent fill ratio,

Article 800 is for communication equipment, you are not dealing with commincation equipment.

Back up to article 725.

ARTICLE 725
Class 1, Class 2, and Class 3
Remote-Control, Signaling, and
Power-Limited Circuits

I. General

725.1 Scope.
This article covers remote-control, signaling,
and power-limited circuits that are not an integral part of a
device or appliance.
 
Article 800 is for communication equipment, you are not dealing with commincation equipment.

Back up to article 725.

Thanks I think I have some fighting ground on getting another conduit run to reduce the cable fill in the other two pipes. It just didn't sit well with me that you can not re-enter the conduit in the future to remove or replace a bad conductor.

Thanks to all for input
 
Yes, it sounds like article 725 as others have stated. But just to comment about Article 800 where there is no conduit fill, its my understanding that you still have to protect the wire from mechanical damage and do it in a neat and workmanlike manner (I know that part is hard to enforce).
2008 NEC 800.24 Mechanical execution of Work says it also has to comply with 300.4(D) and 300.11.

So cramming as many communication wires as you humanly can in a pipe seems to me would be a violation of the NEC, as the mechanical protection of those small conductors would not be there anymore much less be 'neat and workmanlike'. ;-)
 
Status
Not open for further replies.
Top