Disconnect ahead of Industrial Equipment always needed?

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tomleveq

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Confused by NFPA 79 & article 670 concerning what follows.
I have many pieces of industrial equipment ,portable and stationary, that
have supply ckt disconnects on their doors. These disconnects serve as
overcurrent devices as well. Some are fed from a (multi-ckt) wireway
overhead. Is a disconnect (fusible or not) required for the supply
conductors whether or not the protected ckt feeding it is in-sight and
within 50ft.?

I need to get this right once and for all...

Thank you very much,
 
Check 430.102 for disconnects on motor. A disconnecting means can be located remotely from the motor if the plant has a published safety and lockout procedure.

I'm not sure about disconnects on equipment other than motors.
 
... Some are fed from a (multi-ckt) wireway
overhead. ...
How they are fed makes a difference as well. If each one has a home run back to a dedicated circuit breaker in a panelboard, then no, an additional disconnect would not be necessary between the wireway and the equipment disconnect as long as the other LOTO rules are met as pointed out above. But if you are tapping off of a larger conductor (like a form of power bus) to feed one panel at each drop, then you would need circuit protection devices (fuses or a breaker) for those smaller conductors.
 
My plan was to re-route a 60A ckt no longer needed further down in the facility back to a new wireway overhead. I have to portable pieces of equipment to feed. One requires 40amps and the other 20amps. These units are not related electrically. Can I tap the #6awg condustor in the wireway, drop down to a disconnect rated plug & connector, then to the equipment, which has a door mounted, padlockable, disconnect? If I observe the 25ft rule then, the 20 amp ckt is still a 3rd of the feeder ampacity and then I would run the 20 amp conductors in raceway. Is this good?

Tks,
 
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