Compressor breaker size

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leep133

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San Jose, CA
Have a question regarding a 480V, 150HP compressor I am looking to install. The compressor cut sheet shows a FLA of 227A. It also recommends parallel 2/0 CU wire. So far I'm good, what trips me up is that they recommend a 150A fuse. This just seems too low for a 150HP compressor. I would think according to article 430 i should be sizing my wire at 125% of FLA so parallel 2/0 makes sense, although technically parallel 1/0 should work, but shouldn't the breaker be sized at 250% of FLA?
 
Have a question regarding a 480V, 150HP compressor I am looking to install. The compressor cut sheet shows a FLA of 227A. It also recommends parallel 2/0 CU wire. So far I'm good, what trips me up is that they recommend a 150A fuse. This just seems too low for a 150HP compressor. I would think according to article 430 i should be sizing my wire at 125% of FLA so parallel 2/0 makes sense, although technically parallel 1/0 should work, but shouldn't the breaker be sized at 250% of FLA?

I asume thst the way you asked the question that there is no combination motor starter since you made no reference to one. Your question is ambiguous. Or is your objective with this thermal magnetic breaker for feeder protection?
Breakers are ment to protect something, commonly cable. What is this bresker intended to protect, cable or the motor?
Are you referencing NEC art 430?
 
Up to 250% and I think they have a typo.
Time delay fuses would be 175%, but I agree on the typo, I bet it is supposed to be 250 A.

A little more looking and I think there is either more typo or some misunderstanding of what the nameplate might be saying.

430 table 250 says FLA of 150HP is 180 amps. Multiply that by 1.25 and you get 225 amps, maybe there is an additional 2 amps of load for something else in that unit to get OP's mentionedd 227A. Still makes questionable for a 250 amp fuse if across the line starting, but I would bet $1 that this unit likely is controlled by a VFD and that 250 amp fuse would never trip unless there was a fault.
 
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