Running wire in conduit

[Grumpy365]

Can I run an #18/4 conductor shielded cable (Belden 9418 shielded cable) in the same conduit as some #14 THHN control wires (120 volt)

I know it will work, but is it right?

The #18 4 conductor is using a 4-20mA signal to drive a damper actuator and the #14's are breaking the coil of a contactor thru a switch, if it matters.

everything I see says, you can't mix a class 1 and class 2 circuit, but you can if you treat the class 2 circuit as a class 1 circuit (or something along those lines). The Belden cable is a quality cable and is not designated as a class 2 cable, so I am not sure.

 

[rockwithjason]

the cable needs to have the same voltage rating as the control wires

 

[dave67fd]

I's generally considered a no-no. You shouln't mix an analog signal with hi-voltage or you are looking to have excess noise on the signal. It may depend on the actuators ability to reject the noise. We do contols and never mix. If doing in a residential enviornment you can try it to see if you have any problems. The 9418 is a well shielded cable and rated at 300V. If you do it make sure you only ground the shield at the source and not the instrument. You could also use some ferrite cores at the instrument end.