Minimum current ampacity

Other than the requirement for carrying LRA on fire pumps, I can't readily recall any place in the NEC that controls the minimum size of OCPD.

For sure, I regularly used smaller than 125% primary side protection of 75kVA transformers so I could stay in a 100A disconnect.
 
infinity said:
I agree with the inspector. 20 is below the minimum circuit ampacity.
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Although if it were to pull 23A through a 20A breaker and never ran continuously for several hours at a time, the breaker might never trip.
 
ggunn said:
Although if it were to pull 23A through a 20A breaker and never ran continuously for several hours at a time, the breaker might never trip.
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Actually it could pull 115% forever, per UL listing of minature nolded case breakers. OCPD trip curves are based at a specific ambient temperature.
 
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