Functional Features: Provides short-circuit and ground fault protection via a fixed or adjustable magnetic trip. Requires a separate overload relay for thermal protection. Features a robust arc chute design to extinguish arcs during fault interruption.

Application Scenarios: Large pump motors, HVAC systems, compressors, and heavy industrial machinery in manufacturing plants and utilities.

Structural Characteristics: Heavy-duty molded case construction with bolt-on terminals. Includes an operating handle and trip indicator flag.

Installation Requirements: Must be mounted vertically in a clean, dry environment. Requires adequate clearance for ventilation and cable bending radius. Torque specifications must be strictly followed for lug connections.

Precautions: Never operate without a coordinated overload device. Ensure the instantaneous trip setting is correctly calibrated above the motor’s locked rotor current.