<1HP Requirements

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bwat

EE
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EE
For motor less than 1HP, 120VAC, let's say something like 3/4HP, 7.5A FLA.

- The SC/GF protection can be from 20A CB that feeds general use receptacle that will be source of supply
- The OL protection can be from the same 20A CB (motor is not automatically started, not permanent, is stationary, and will be within sight of controller)
- The Controller can be a switch as defined in 430.83(C)

So far so good. I just need some type of applicable switch, like a 15A snap switch, to be considered my controller.

But then the disconnect requirements...

- 430.102(A) Requires the controller to have a disconnect
- 430.109(C) States that the same type of switch that I can use as my controller, can be used as my disconnect

So can the same snap-switch be considered both the controller and the controller disconnect?

430.111 lists requirements for being both controller and disconnect. Would a snap switch be considered an air-break switch in this context? If not, it would almost seem like I would need a snap-switch upstream from my snap-switch.. which doesn't seem right. Hence my posting here.


Receptacle, switch, and motor all to be in same room.
 
Need the switch be HP-rated?
I don't think so per 430.83(C) and 430.109(C)

Edit: A nice person would have posted the sections rather than just list them. Sorry.

430.83(C) Stationary Motors of 2 Horsepower or Less. For stationary
motors rated at 2 hp or less and 300 volts or less, the
controller shall be permitted to be either of the following:
(1) A general-use switch having an ampere rating not less
than twice the full-load current rating of the motor
(2) On ac circuits, a general-use snap switch suitable only for
use on ac (not general-use ac–dc snap switches) where
the motor full-load current rating is not more than
80 percent of the ampere rating of the switch

and
430.109(C) Stationary Motors of 2 Horsepower or Less. For stationary
motors rated at 2 hp or less and 300 volts or less, the disconnecting
means shall be permitted to be one of the devices
specified in (1), (2), or (3):
(1) A general-use switch having an ampere rating not less
than twice the full-load current rating of the motor
(2) On ac circuits, a general-use snap switch suitable only for
use on ac (not general-use ac–dc snap switches) where
the motor full-load current rating is not more than
80 percent of the ampere rating of the switch
(3) A listed manual motor controller having a horsepower
rating not less than the rating of the motor and marked
“Suitable as Motor Disconnect”
 
Sounds like a single switch is okay, but I'd probably opt for one rated for greater current, like a 20a or 30a switch.
 
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