Quick question....
I was just reading NFPA 79 concerning supply circuit disconnects. What I would like to know is, is there a minimum voltage that an external disconnect (e.g operating handle connected to a molded case circuit breaker) is required? I have always seen them used on enclosures with 380/460/480 vac. But would an enclosure that has an incoming supply voltage of 110vac be required to use such a device? What about 220vac?
