DC Power & Interference of Ethernet Signal

[mvpieper]

I am planning the installation of DC power distribution and Ethernet in an industrial facility. I intended to place both 24VDC power (up to 10 amps) and Cat6 cable in the same conduit; however, the building owner has requested that they be placed in separate conduit.
All conduit is 'rigid' metallic. Ethernet communication is actually 100Mbps in a 'ring' topology to several VFD enclosures. I intend to use shielded Ethernet cable.
The total length of the ring is perhaps 1000 feet with 10 or so VFD enclosures (each VFD enclousure has a ring switch). I assume that DC power in its self would not be the source of any interference and thus assume that the concern is inadvertent construction of an antenna with the DC power distribution conductors. How real is this concern, especially considering that I am using shielded Cat6 and metallic conduit?
Am I missing something or is my client just throwing money at some unknown problems from his past installations? Any advice is appreciated.

 

[VEBill]

It's a perfectly reasonable precaution. The DC conductors might be carrying noise, especially in common mode. Shielding on the Ethernet will certainly help, but it's probably a case of better safe than sorry.

 

[itsmoked]

I would want them in separate conduits simply because they are different 'things'. In a few years he might need to switch to fiber or add more CAT9. Having different styles of cable can make pulling new stuff really hard - been there - don't want to be again!

Keith Cress
kcress -

http://www.flaminsystems.com