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Switching a motor - switch rating question

Switching a motor - switch rating question

Switching a motor - switch rating question

(OP)
Hello there,

Long time lurker. I've gotten tons of useful information off this forum, so a general thanks for all your contributions.

I have a motor I need to add a spst switch to. My question is to make sure I select a switch that is ample to handle the switching current. My background is mechanical and I could use some clarification.

The motor I need to switch is a 120v, 1hp rated @ 12.8 amp service factor @ 120vac. The switch I'm looking at does not list the 120v amp rating, instead is specifies max amperage at 600vac to be 28amps. They list the 120v HP rating at 1hp. Will this switch be sufficient for the motor? Can anyone explain the correct way of converting this 600vac amp rating to 120vac?

Thank you all.

RE: Switching a motor - switch rating question

(OP)
I'm sorry, correction, the 600vac rating is 32 amps. There is also another one that is 50 amps @ 600vac, lising 1.5hp @ 120vac as the max hp. Which one should I go with but more inportantly any specific info on conversion would be appreciated.

RE: Switching a motor - switch rating question

That is what the HP ratings of switches and contactors are for.  

Rafiq Bulsara
http://www.srengineersct.com

RE: Switching a motor - switch rating question

(OP)
Thank you very much. I do not like to be on the limit of any device so I will spec. the 1.5hp rated switch.

I appreciate the input.

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