Motor protection circuit breakers: functions and selection
A motor protection circuit breaker (MPCB) protects an electric motor against overloads and short circuits while providing manual switching and isolation. Its adjustable thermal setting should be matched to the motor’s rated current and operating conditions.
Key selection parameters
- Current adjustment range: the motor’s rated current must fall within the breaker’s adjustable range.
- Short-circuit breaking capacity: select a device suitable for the prospective fault current at the installation point.
- Poles and supply system: most three-phase motor circuits use a 3-pole MPCB.
- Coordination: verify compatibility with the contactor, cable, motor starter and upstream protection.
- Accessories: auxiliary contacts, shunt trips and enclosure options can support control and monitoring requirements.
ABB and Schneider Electric motor protection
PowerOn offers ABB and Schneider Electric solutions for motor feeders and control panels. Compare available adjustment ranges and accessories in the motor protection circuit breaker collection, and pair the selected breaker with a compatible device from the contactors collection. Final sizing and coordination should be confirmed by a qualified electrical professional.
