Ul 508a

[jim dungar]

UL508A 66.9.1 specifies the color of wirs for grounded control circuits.
Any voltage AC - white or natural gray
Any voltage AC remaining energized when main is off - white/yellow stripes
Any voltage DC - white/blue stripes

There are no other conditions of grounded circuits allowed, therefore there is no need for additional colored stripes.

However, Section 66 is only applicable to "specific application industrial control panels", see 65.2.

There are no color restristrictions for "general use industrial control panels", see Section 38.

 

[sagman]

Ul 508a

I have a question regarding the wire color codes for UL 508A (Electrical control panels). There are a couple classifications of panels in this standard, relating to industrial machines, and general control panels. I have a customer that wants to use striped wire in their panels (NOT used on an industrial machine) to designate I/O to the PLC and such, however someone is telling me that the revised code from Sept 2005 does not allow it.... see the following:

On the wire color issue, the state of Oregon requires all control panels to be UL-508 listed. UL has wire color code requirements that went into effect September 1, 2005, so we are bound to these requirements in order to have the panels pass the on-site electrical inspection. The striped conductors are not allowed, except for the White with Blue stripe for grounded DC conductors, and White with Yellow stripe for foreign AC voltage neutrals.

Does anyone know if this is true? I would think that a drastic change in wire code standards would be more well known in the industry, and this is the first I've heard of it.

Thanks for any help on this matter.

Steve