Cat 5 wire in main electrical panel

[Joshua D. Lutz]

Ran into this today doing a new construction final. Any issues with having the low voltage network cable in the main electrical panel enclosure or in the conduit with the other wires? The builder said it is for future smart meter installation but I don't know why it would be in the panel for that.


Any input would be appreciated.

Thanks

[Jeffrey R. Pope]

Not allowed.

[Joshua D. Lutz]

Thanks Jeff, I was pretty certain it wasn't allowed but had to follow up and check. Would you be able to point me in the direction of some documentation to send the builder?

Thanks

[Jeffrey R. Pope]

It's covered in Article 800 of the NEC (maybe a sparkie can help out with the best reference for this case), but it's referenced as "separation from other conductors."

[Michael Larson]

The issue is that in case of a wiring fault you could have high voltage on the low voltage conductors and going to equipment and insulation systems that aren't designed to handle it.

[Robert Meier]

Looks like there may be more than just a problem with the CAT5 cables but here's the relevant section from the 2008 NEC:

800.133 Installation of Communications Wires, Cables, and Equipment.
Communications wires and cables from the protector to the equipment or, where no protector is required, communications wires and cables attached to the outside or inside of the building shall comply with 800.133(A) through (C).
(A) Separation from Other Conductors.
(1) In Raceways, Cable Trays, Boxes, and Cables.
(a)Other Power-Limited Circuits. Communications cables shall be permitted in the same raceway, cable tray, or enclosure with cables of any of the following:
(1) Class 2 and Class 3 remote-control, signaling, and power-limited circuits in compliance with Article 725
(2) Power-limited fire alarm systems in compliance with Article 760
(3) Nonconductive and conductive optical fiber cables in compliance with Article 770
(4) Community antenna television and radio distribution systems in compliance with Article 820
(5) Low-power network-powered broadband communications circuits in compliance with Article 830
(b) Class 2 and Class 3 Circuits. Class 1 circuits shall not be run in the same cable with communications circuits. Class 2 and Class 3 circuit conductors shall be permitted in the same cable with communications circuits, in which case the Class 2 and Class 3 circuits shall be classified as communications circuits and shall meet the requirements of this article. The cables shall be listed as communications cables.
Exception: Cables constructed of individually listed Class 2, Class 3, and communications cables under a common jacket shall not be required to be classified as communications cable. The fire-resistance rating of the composite cable shall be determined by the performance of the composite cable.
(c) Electric Light, Power, Class 1, Non–Power-Limited Fire Alarm, and Medium-Power Network-Powered Broadband Communications Circuits in Raceways, Compartments, and Boxes. Communications conductors shall not be placed in any raceway, compartment, outlet box, junction box, or similar fitting with conductors of electric light, power, Class 1, non–power-limited fire alarm, or medium-power network-powered broadband communications circuits.
Exception No. 1: Where all of the conductors of electric light, power, Class 1, non–power-limited fire alarm, and medium-power network-powered broadband communications circuits are separated from all of the conductors of communications circuits by a permanent barrier or listed divider.
Exception No. 2: Power conductors in outlet boxes, junction boxes, or similar fittings or compartments where such conductors are introduced solely for power supply to communications equipment. The power circuit conductors shall be routed within the enclosure to maintain a minimum of 6 mm (0.25 in.) separation from the communications circuit conductors.
Exception No. 3: As permitted by 620.36.
(2) Other Applications. Communications wires and cables shall be separated at least 50 mm (2 in.) from conductors of any electric light, power, Class 1, non–power-limited fire alarm, or medium-power network-powered broadband communications circuits.
Exception No. 1: Where either (1) all of the conductors of the electric light, power, Class 1, non–power-limited fire alarm, and medium-power network-powered broadband communications circuits are in a raceway or in metal-sheathed, metal-clad, nonmetallic-sheathed, Type AC, or Type UF cables, or (2) all of the conductors of communications circuits are encased in raceway.
Exception No. 2: Where the communications wires and cables are permanently separated from the conductors of electric light, power, Class 1, non–power-limited fire alarm, and medium-power network-powered broadband communications circuits by a continuous and firmly fixed nonconductor, such as porcelain tubes or flexible tubing, in addition to the insulation on the wire.

[Joshua D. Lutz]

Thanks for the info Robert. Other problems were noted in the report but my question was about the Cat 5.