Comm and Power Separation

[mikeybmdb32]

Is the purpose of the separation between communications and power required by NESC 320.B.2 intended to prevent heat transfer from the power conductors to the comm conductors or to prevent induction of voltage from the power conductors onto the comm conductors?

 

[tom baker]

The 2011 NEC has no 320.B.2.....
300.3(C)(1) has the seperation requirements. Its often misquoted to not require seperation if all conductors have insulation rated for the maximum circuit rating.
Read 90.3
Read 300.3(C)(1)
The read the IN, and its reference sections.

Seperation is required in the event of a short from the line voltage to the limited energy side. The limited energy equipment can't withstand the higher voltage and can fail, possibily causing a fire or shock.

NEC does not care about induction, IE if it doesn't work, thats not our concern, to understand this, see the purpose of the NEC in section 90.1

 

[mikeybmdb32]

clarification

clarification

Sorry, should have clarified, i was referring to the national electrical safety code (IEEE C2). Very well put, but would the intention of the NEC sections you've mentioned be the same as the intention of IEEE C2's requirement for having 12" (of earth) separation between comms and power? I think it would, but I figured I would ask ...

 

[infinity]

I'm not familiar with the NESC but you can find information about the National Electrical Safety Code here:

http://standards.ieee.org/about/nesc/

Generally the NEC doesn't care if you run communication and power cables next to each other.