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Will an 80% rated circuit breaker trip if 80% of its rating is exceeded?

Issue:
80% rated breaker performance at over 80% of handle rating
 
Product Line:
Molded case circuit breakers
 
Environment:
Electrical distribution systems
 
Resolution:
NO.  The 80% rating is an NEC restriction designed to prevent over-heating and nuisance tripping of enclosed breakers and breakers in panelboards and switchboards which may experience a heat build-up due to air-flow restrictions and the thermal contributions of other breakers.
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