OT: is anyone here a UL508 shop?

[J Tiers]

We had a question about a supposedly UL508 compliant panel..

The way we understand the wire color requirements is not what we are looking at now. We understood that the highest AC voltage is black with gray neutral, all other AC wires are red, except 120V neutral which is white, and all DC wires are *either* blue or blue with black stripe. All other wire designation is by wire numbers, not color.

Is it permissible to use the blue/black stripe for DC+ and the blue for DC-? That seems to have been done in a panel, and we are not sure it is legit.

It makes tracing easier, but we didn't think it was OK.

Anyone know for sure?

[Evan]

Xerox uses purple (not blue) for DC common and orange for DC+ with wire numbers.

[rdfeil]

J Tiers,

I am not a UL508 shop but ETL. What you describe is very close to the ETL color requirements (the blue and blue W/stripe are what ETL requires). As for the black and red thing... ETL requires all "supply connections" to be black and all derived AC voltage wiring to be red, irrelevant to the voltage. For example, A panel supplied with 120 Volts 1 phase that has a VFD that converts to 240 3 phase would be wired as follows: All incoming power connections, fuses, switches and terminal connections would be in Black on the line leg and White on the neutral. The output of the VFD to the motor (240 3 phase) would be RED. The low voltage control wiring (start, stop speed etc) would be Blue and/or Blue with stripes. This is ETL and I don't know how close UL508 is.

If you are concerned give UL a call and ask them for their wiring specifications for a 508 panel. The other thing is that it is the panel shops butt that is on the line if it is wrong. As long as it has the UL508 label you are off the hook

It seems to me that UL508 color requirements are more lax than ETL, but don't quote me on that.

Robin