What type of breaker is required for proper overcurrent protection of a three-phase motor?

A triple-pole breaker is essential for providing overcurrent protection for a three-phase motor because it includes three separate poles which correspond to the three phases of power used by the motor. Each pole functions independently to interrupt the circuit in the event of an overcurrent situation, ensuring that all phases receive the same level of protection simultaneously.

Using a triple-pole breaker allows for coordinated tripping; if one phase experiences an overload and trips, the breaker will cut off power to the other two phases as well. This is crucial for maintaining balance and preventing phase loss, which could otherwise lead to motor damage.

In contrast, a single-pole breaker would only protect one phase, leaving the other two phases unprotected, and a double-pole breaker, while capable of protecting two phases, would still fail to provide comprehensive protection for a three-phase motor. A quad-pole breaker, not typically used in standard three-phase configurations, would not apply because only three phases are present in such systems. Thus, the triple-pole breaker is the proper choice to ensure effective overcurrent protection for a three-phase motor.