Several motors or loads on one branch circuit NEC430.53

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paulbr

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am looking for some help.:-?
For HVAC unit I have three Copeland compressors units, which are connected (piped) in tandem. Each compressor rated three phase 460V, 60Hz,load current is 18.6 amp. Each compressor will operate from its own contactor rated for 34 amp equipped with electronic overload relay adjustable range 15-45.
Am I allowed by NEC have only one branch circuit protection circuit breaker for all three compressors? If yes, how to size it? I was reading NEC paragraph 430.53,and got lost.
Thank you,

PaulBr.
 
Dennis Alwon

Dennis Alwon

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Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
I don't think you can have a branch circuit that large and still satisfy the requirements of OCP etc. Perhaps you mean a feeder-- run a feeder to a small breaker box and then feed each unit from there.

I believe you could take the FLA of all 3 units and then multiply the largest unit by 125%. I know this is true for motors so I am assuming this is okay for a/c units
 
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