Wire Sizing for Mini Split

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I'm curious as to what NEC code you think would be cited to fail a 30 amp breaker installed on this particular unit. Continuous load is less than 24 amps.

To answer the OPs question, #10 is fine provided you aren't wiring this thing in a ridiculously hot ambient temperature and/or contending with a long run of wire.

And because it has not been mentioned, one could use a combination of fuses and Breakers as well, even mismatched ones like a 40 amp breaker and 35 amp fuses

Amen, table 430.52 allows a range of OCPD serving a motor circuit.

If the question is about code legality, you are allowed to increase the OCPD size feeding a motor circuit while keeping the conductors sized for 125% of nameplate current. If it is a question about good design practices, then you would want to dial in that OCPD as close to the nameplate load as possible.
 
Amen, table 430.52 allows a range of OCPD serving a motor circuit.

If the question is about code legality, you are allowed to increase the OCPD size feeding a motor circuit while keeping the conductors sized for 125% of nameplate current. If it is a question about good design practices, then you would want to dial in that OCPD as close to the nameplate load as possible.


If the nameplate states max overcurrent protective device @40 amps then you cannot install a larger device.
 
IF it was being used as the OCPD, correct? You could use a fused 60A disconnect at the machine, if it's fed from a 40A breaker, right?

Yes that is true or we wouldn't even need a fused disconnect at the unit if you buy into the fact that a fuse is not needed.
 
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