What ambient conditions are acceptable for operation and storage of Powerpact H, J, and L frame circuit breakers?
What considerations must be made for ambient temperature, humidity, altitude, and vibration when storing or operating Powerpact H, J, and L frame circuit breakers?
Powerpact H, J, and L frame circuit breakers
PowerPact™ H-, J-, and L-frame circuit breakers may be used at ambient temperatures between -13°F and 158°F (-25 °C and +70 °C). For temperatures higher than 104° F (40° C) inside the enclosure, devices must be derated. See attachment for specific rerating factors for both thermal-magnetic and Micrologic (electronic) trip breakers. Circuit breakers should be put into service under normal ambient operating-temperature conditions.
Altitude does not significantly affect the characteristics of PowerPact H-, J-, and L-frame circuit breakers circuit breakers up to 6560 ft (2000 m). Above this altitude, it is necessary to take into account the decrease in the dielectric strength and cooling capacity of air.
At altitudes greater than 6560 ft. (2000 m), rerating factors apply; see attachment for details.
It is recommended that the equipment be cooled or heated to the proper operating temperature and kept free of excessive vibration and dust, and be protected from water intrusion and condensation.
See attachment for recommendations regarding vibration, humidity, frequency, and storage.