UL508 Disconnect vs UL98 Disconnect

[rpm3232]

When is it OK to use a UL508 Disconnect in place of a UL98 disconnect on a UL508A listed panel? We have a panel that mainly controls a motor, but has other circuits (ie. PLC, I/O). This must go through UL certification soon. I have heard multiple explanations on this and could use a NEC 409 reference or UL508A. The panel, nor the equipment it controls, is not classified as "Industrial Machinery".

 

[DRWeig]

If your switch is required to be suitable as a motor disconnect or manual motor controller, it needs to be marked as such -- and UL 508 applies. (UL 508A 30.1.5 and table SA-1).

If not required to be suitable as a motor disconnect or manual motor controller, it can be UL 98. (UL 508A 30.1.4 and table SA-1).

Those are my opinions; the opinions of your UL field inspector may vary. Best suggestion: ask him.

Good on ya,

Goober Dave