Issue:
Is it acceptable to use wire with 90 deg. C insulation on a molded case circuit breaker?
Product Line:
All MCCBs; legacy and Powerpact
Resolution:
It is acceptable to use conductors with a higher insulation rating than what is marked on the breaker, but the ampacity must be based on the conductor temperature rating marked on the breaker. So, circuit breakers marked for use with 75 deg. C rated conductors may be used with conductors rated for 90 deg. C if the conductors are sized per their 75 deg. C ampacity.
Is it acceptable to use wire with 90 deg. C insulation on a molded case circuit breaker?
Product Line:
All MCCBs; legacy and Powerpact
Resolution:
It is acceptable to use conductors with a higher insulation rating than what is marked on the breaker, but the ampacity must be based on the conductor temperature rating marked on the breaker. So, circuit breakers marked for use with 75 deg. C rated conductors may be used with conductors rated for 90 deg. C if the conductors are sized per their 75 deg. C ampacity.