On Sat, 14 Mar 2020 15:14:01 +0000, BillH
m wrote:

replying to hrhofmann, BillH wrote:
Low voltage wires for control circuits are typically twisted pair, which gives
significant protection from picking up signals from other wires running
parallel. Using a 14 gauge power cable in this scenario could result in the
60 cycle power lines inducing voltage at 60 cycles into the low voltage
control wires.

You are never going to induce enough voltage to pick a relay and that
would usually be what is at the end of an unshielded or untwisted
pair. Any electronic circuit should be designed to reject incidental
60 hz noise. The real issue with class 2 and 3 wires in conduits is
safety, isolation and how they get terminated. As a general rule you
will not see them in the same conduit as mains voltages because of
those rules in the code even if both are cable type wiring methods
that meet the isolation requirement. Then the issue is termination.
If it is class 1 low voltage, they are treated just like mains
voltages.