Cat 5 wire in main electrical panel

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.


Not allowed.

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?


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.”

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.

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

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