Small-sized low-voltage circuit breakers can be divided into two types: universal type (also called frame type, internationally known as ACB) and plastic case type (internationally known as MCCS, NICB). They have the same role as: In normal circumstances, do not frequently make and break the circuit to start and stop the motor; when the line or motor has an overload, short circuit or undervoltage (undervoltage) and other faults, it can automatically cut off the circuit, protection.
Circuit breakers are divided into four types depending on the protection object:
Distribution protection type - protection of power and electrical lines (wires, cables) and equipment; motor protection type - designed for frequent starting of the motor, breaking during operation, and protection against overload, short-circuit and undervoltage of the motor; And similar home-site protection type - the protection of lighting circuits, household appliances, etc.; residual current (earth leakage) protection type - used to protect people from electric shock hazards and prevent electrical fire protection device.