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UL 508A disconnect clarification questions

UL 508A disconnect clarification questions

UL 508A disconnect clarification questions

(OP)
How does AB and others produce 508A industrial control panels with a motor starter (such as the Bulletin 530 & 570) without using a disconnect switch?

Furthermore, for any disconnect (fused or non-fused switch type) do I understand correctly that in order to be used as an industrial control panel disconnect it must have the WHTY CCN rather than the NLRV CCN?  I read it as the NLRV is intended for use as an individual motor disconnect rather than an industrial control panel disconnect.

 

RE: UL 508A disconnect clarification questions

They are called "Non-combination motor starters". The definition of a motor starter is a control device (contactor) and motor thermal overload protection. Adding in the Over Current Protective Device (OCPD) and local disconnect is an optional arrangement. It saves on installation cost to have them all in the same box, but it is not a requirement that they be. The requirement is only that each motor circuit has those elements, but there is nothing wrong with their being in separate enclosures.


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