Is it ok to run multiple CAT3 and CAT6 cables next to each other?

Question

Is it ok to run multiple CAT3 [ADSL2+] and CAT6 cables next to each other, including within a wall, for a 20m - 30m run?

Answer 1

Yes, as each cable has twisted pairs to prevent EMF interference, with each twisted pair's twist being a different length than the others.

• Ethernet and phone cables operate at low voltage and amperage; the only thing to avoid would be placing them next to AC power cables.
  • While it's unlikely running a bundle next to a few AC power cables would negatively affect the data being transmitted, it's best practice to run AC power cables separately from low voltage data lines, whether they be audio, video, or ethernet/phone lines, and if low voltage data lines must intersect AC power cables, it's best practice to do so at right angles to prevent EMF interference.
    
    

When running through walls, ensure cabling is:

• CMP rated, as CMP cable jackets are fire-resistant
  • U.S. NEC requires CMP jackets for any data cables run within an enclosed plenum cavity as they smolder out quickly upon catching fire
• Not run within the same space as electrical wiring, else EMF interference is a real possibility
  • U.S. NEC requires this as well IIRC

Answer 2

Yes, of course. In datacenters, we have bundles of dozens and dozens of cacat5/cat6 running together.

Answer 3

Yes, this is fine.

What you should not do is run network cable directly adjacent to power cabling. I generally try follow what I like to call the "Rule of 6": if power and data lines will run alongside each other for 6 feet or more, they should be at least 6 inches apart — though circumstances don't always allow this.