UL 508 labelling

[Will Weber]

I understand why the requirement for the UL508 certification. As an general construction inspector I need to know if a control panel / enclosure is UL508 compliant. What do I look for? Does the labeling have to say UL508? I checked NEC 409 and that did not help much. Mike's book jumped right over NEC 409, so no help there.

 

[kc8dxx]

Our panels have a sticker on it, with a UL logo, a serial number, and a title "Enclosed Industrial Control Panel". I have seen stickers on purchased control enclosures with an ETL logo and similar information. None of the stickers I have seen have UL508A or NFPA79 or similar text. I'm sure that other readers have seen quite a variety of stickers.

 

[davidr43229]

I understand why the requirement for the UL508 certification. As an general construction inspector I need to know if a control panel / enclosure is UL508 compliant

Within the 2005 Article 409 and UL508A a nameplate that states:
(1) Manufacturer's name, trademark, or other descriptive marking by which the organization responsible for the product can be identified.
(2) Supply voltage, phase, frequency, and full-load current.
(3) Short-circuit current rating of the industrial control panel based on one of the following:
a. Short-circuit current rating of a listed and labeled assembly
b. Short-circuit current rating established utilizing an approved method
FPN: UL 508A-September 2005, Supplement SB, is an example of an approved method.
(4) If the industrial control panel is intended as service equipment, it shall be marked to identify it as being suitable for use as service equipment.
(5) Electrical wiring diagram or the number of the index to the electrical drawings showing the electrical wiring diagram.
(6) An enclosure type number shall be marked on the industrial control panel enclosure.

Then it is up to you IMO to ensure that the Available Fault Current does not exceed the SCCR rating of the panel, if you are the AHJ (authority of having juristiction).

Just my $.02

 

[MO_EE]

UL mark

UL mark

A 508A panel should be marked "industrial control panel" with the UL logo. Be careful not to mistake the label of the enclosure for the label of the assembly. Article 409 requires the panel to be labeled with assembly withstand as well. Like stated above the inspector must ensure the panel is not installed where the available fault current is greater than the assembly SCCR.