Thru-Door Disconnect

[billalex23]

On Industrial control enclosures (PLC-type enclosures) IF the power supply to the enclosure is 120VAC (or below) single phase, IS THRU-DOOR INTERLOCK REQUIRED? Commonly door-interlocked breakers are only available in 3-pole configuration.

 

[Kiljoy]

It depend is it is a standalone box or part of machinery. If it's by itself then...

60.2 An industrial control panel provided with a separately supplied control circuit where the
disconnecting means and/or branch circuit protection is omitted shall be marked to indicate that these
devices shall be provided by the installer.

If it's part of machineery then I don't think so. I've seen 120vac boxes with disconnects where they only used 2 of the three poles.

 

[dbaird]

In the USA, NFPA 79 alows an attachment plug and receptacle as the supply disconnecting means per:

David Baird

Sr Controls Designer
EET degree.
Journeyman Electrician.