Circuit breaker is getting hot, how much heat is allowed?

Answer

All units will get hot under 100% rated current. Dependent on the cable size used and the atmospheric temperature, the operating temperatures could be affected.

All breakers are expected to operate at 40 Degrees Celsius. Thermal Breakers de-rate after 40 Degrees Celsius, but CBI hydraulic-magnetic circuit breakers do not de-rate until 85 Degrees Celsius.