UL PLC/switchboard wiring

Hello

Im have a problem about the wiring in switchboards. The switchboards should be UL listed and the wire colours i should use is a problem.

I have a analog signal from the PLC going to terminals and then to the transmitter. Witch colours should the wiring be?

Does anybody have a list or something that describes all the used wire colours in UL standards?'

Thanks

Try searching in the forum, I'm sure this has been asked before.

Hello,
UL has a standard for just about everything on the planet so I am not going to say there is no standard but my question is what UL standard are you building the panel or device to?

If it is UL508A which is the standard that we use in the US for most Control Panels, as far as I know there is no "standard" wire colors called for in that standard. I typically stick with Blk, Wht & Grn for AC wiring and Red, Blk for DC power with Wht being a signal wire.

I know a lot of people use Blue with Wht strip and Wht with a Blu strip for DC power. The wire can kind of a pain to get as it is not normally stocked but it is not a bad idea. Keeps form getting Blk in AC confused with Blk in DC.

My advice is absent of a clear standard that your customer is requiring, I would pick my colors and stick with them throughout your builds. It is easier to spot if something is wired wrong when you are doing your QC of the panel.