The Allen-Bradley/Rockwell Automation 140G-J3F3-D10 circuit breaker is a 3-pole circuit breaker. It has a molded case. Breakers with a molded case are smaller than other breakers and they save mounting space. Additionally, molded case circuit breakers such as the 140G-J3F3-D10 circuit breaker take less time to reset and or switch on after they trip during electrical faults. The 140G-J3F3-D10 circuit breaker, like other 140G circuit breakers, contains a handle that indicates whether the breaker is ON, OFF, or TRIPPED. The RESET option is beyond the OFF position and it is used to bring the 140G-J3F3-D10 circuit breaker back into operation after a trip.

However, before resetting the circuit breaker, it is recommended that the underlying problem be investigated and corrected. Failure to do this may result in multiple trips, which could cause severe device damage. Note that the molded case is either made of a thermoset composite resin that combines durability and high dielectric strength in a compact design or a glass-polyester material. The operating mechanism of the 140G-J3F3-D10 circuit breaker handles the closing and opening of the contacts. Note that the breaker cannot be prevented from tripping by holding the handle in the ON position. The Allen-Bradley 140G-J3F3-D10 circuit breaker extinguishes an arc by confining and dividing an arc which is formed each time the breaker interrupts current flow. An arc extinguisher is mainly made of a stack of steel plates held together by 2 insulating plates. Since the 140G-J3F3-D10 circuit breaker’s trip unit has a thermal element, the environment’s ambient temperature has to be considered before mounting because high temperature can cause the thermal trip unit to malfunction.