Power & Communication Separation

[NEC User]

I know power and copper communication cables are required to be installed in separate conduits and pull boxes. What specific section of the NEC requires this?

Best I could find is 770.133 for independence of fiber.

Thank you.

 

[augie47]

For communications circuits in general, 800.133

 

[cadpoint]

For Conductors of Different Systems, 300.3(C)(1), 600 Volts,
Nominal, or Less (11')

 

[don_resqcapt19]

For Conductors of Different Systems, 300.3(C)(1), 600 Volts,
Nominal, or Less (11')

But make sure you also read Informational Note #1.

 

[m sleem]

As per 800.133(a)(2) 50mm min distance between telecom systems & power/lighting systems,

For other codes TIA/EIAIf power/lighting ckt larger than 2kva the distance shall not be less than 130mm,
If power/lighting ckt larger than 5kva the distance shall not be less than 600mm.

 

[don_resqcapt19]

As per 800.133(a)(2) 50mm min distance between telecom systems & power/lighting systems,

For other codes TIA/EIAIf power/lighting ckt larger than 2kva the distance shall not be less than 130mm,
If power/lighting ckt larger than 5kva the distance shall not be less than 600mm.

Exception #1, in most cases, permits installation with no separation between the power and communication cables. Other standards require separation, but they are base on system performance and the NEC is only looking at this from a safety standpoint.

 

[greenspark1]

Exception #1, in most cases, permits installation with no separation between the power and communication cables. Other standards require separation, but they are base on system performance and the NEC is only looking at this from a safety standpoint.

Yes they are allowed together but 725.136 prohibits class 2 or 3 to be installed with power, lighting, class 1, etc unless separated by a barrier.

Unclear if the insulation of the cable counts as a barrier, but I wouldn't think so. Less clear is if you can run AC cable in the same conduit as twisted pair comm cabling.

 

[don_resqcapt19]

Yes they are allowed together but 725.136 prohibits class 2 or 3 to be installed with power, lighting, class 1, etc unless separated by a barrier.

Unclear if the insulation of the cable counts as a barrier, but I wouldn't think so. Less clear is if you can run AC cable in the same conduit as twisted pair comm cabling.

It is my opinion that 725.136(I) permits the installation without any type of barrier. Since there is no specific subsection that covers the two systems within a raceway, it appears to me that "(I) Other Applications" would apply where you have multiple systems in a common raceway.