Rating of Disconnect switch

[jkim780]

Disconnect switches(Safety switches) have three different ratings. Voltage rating, Amperage rating, & Horsepower rating. How are they different? Why they have three different ratings?
(I understand the voltage rating and amperatge rating. But why horsepower rating?)

Thanks for your answers.

 

[earlydean]

Re: Rating of Disconnect switch

A motor circuit switch is rated in horsepower to match the switch to the motor. the amperage rating is also included so the switch could be sized correctly for non-motor uses. Saves on inventory. A motor circuit switch is designed to handle the large inrush of current for motor starting. Not all motors require motor rated switches. See article 430 part IX.