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Posted By: Elzappr 3-way exhaust fan disconnect - 02/03/05 10:02 PM
Can a 3-way switch set serve as a disconnect for a small exhaust fan?
Since the code allows (225.38 exception) 3-ways for a residential garage disconnect, it would seem ok to do the same for the exhaust fan. Yet, it seems a bit dangerous to rely of turning off the circuit with a 3-way, and hoping that someone doesn't come along and flip the out-of-sight switch while you are working on the wiring.
Posted By: iwire Re: 3-way exhaust fan disconnect - 02/03/05 10:17 PM
No a 3 way switch can not be a disconnecting means.

A disconnecting means must have a clearly labeled off or open position.

Depending on your exhaust fan one of these will apply.

Appliances
Quote
422.35 Switch and Circuit Breaker to Be Indicating.
Switches and circuit breakers used as disconnecting means shall be of the indicating type.


Motors
Quote
430.104 To Be Indicating.
The disconnecting means shall plainly indicate whether it is in the open (off) or closed (on) position.
Posted By: Tom Re: 3-way exhaust fan disconnect - 02/03/05 10:31 PM
If you approach this strictly as a motor load, 430-104 requires the disconnecting means to "plainly indicate whether it is in the open(off)..." 430-109 Exception 2 would be the required disconnect (branch circuit breaker), since most of these exhaust fans have very small motors.

Or, if the fan is an appliance, which, IMO it is, then 422.31(A) applies iand you still end up with the branch breaker being the disconnect.

(and while I'm looking this up, IWire beats me to the punch)
Tom

[This message has been edited by Tom (edited 02-03-2005).]
Posted By: Elzappr Re: 3-way exhaust fan disconnect - 02/03/05 11:11 PM
Ok, so if the motor is dinky (<1/8hp) and the branch circuit breaker serves as the REQUIRED disconnect, are the 3-ways illegal? Are the 3-ways considered just a controller, since they aren't adequate as a positive means for isolating the motor?
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