I agree except I believe that once the class 1 conductors leave a class 1
location, they can be transitioned back to class2. For example, and air
handler built by "First", instead of running class 2 low voltage into the
unit and make connections on an isolated board, they run what appears to be
MTW out of the machine and leave tails for connection to class 2 low
voltage. Similarly, in any AC condenser, your class 2 conductors are
connected to line voltage conductors before entering the line voltage
compartment for connection to the contactor



"Bud--" wrote in message
.. .
RBM wrote:
You could run the low voltage with the line voltage if you use "line
voltage" conductors, which will probably be rated 600 volts, and although
'THHN is often bantered about as the conductor of choice, keep in mind it
is not rated for wet locations. Most, but not all conductors have
multiple ratings, so for wet locations be sure it has a letter "W" in it
like THWN


I believe mixing the power and control wires in the same conduit changes
the Class 2 control circuit into a Class 1 circuit. A Class 1 circuit
generally has to be wired as normal line voltage circuits - Romex, EMT,
boxes; #18 may be used if appropriate. That would apply to all the control
circuit connected to those wires, like the wiring to the thermostat.
Control wires in the disconnect makes the control circuit Class 1 also.

Line and low voltage wiring can go to the same enclosure when connecting
to the same device in that enclosure, like a relay.

You could probably mix UF (instead of Romex) for power plus a control
cable in the same conduit (but I didn't look it up).

--
bud--