Sizing OCP for condensing units

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CrappyFishRman

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Dubuque, Ia
I'm a little stumped on how to size everything. Here's the info i have and what I believe i need for everything. 208v single phase condensing unit. RLA 15, LRA 87, and amps 16.1. This is a print off from the website of the electrical info. I wish the unit was here and I'd just look at that. I used %125 to calculate wire size. Looks like #12's will work fine. And for over current protection i did %175. Which gives me 30 amps. Thing that is throwing me for a loop is the locked rotor amps of 87. Wouldn't that trip a 30 amp breaker??? Any help would be great. Fyi commercial install.
 
Normally the unit nameplate will have a Minimum Circuit Ampacity and a Maximum OCPD or Maximum Fuse size.
Those tell you all you need to size the wires and the breaker.

PS: The motor will not draw LRA for very long. As long as it is below the instantaneous trip of the breaker it should not be a problem. If the LRA is drawn long enough to trip the breaker, it will be protecting the motor from damage.
 
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I would call the hvac guy and get the minimum circuit ampacity. If that is 16 amps then #12 is good however depending on the distance you may want to go with #10-- Seems like 3/4" emt will do you fine.

The LRA will not trip the 30 amp breaker if that is the maximum required by the unit
 
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