Miniature Circuit Breaker Terminal protection appliances

Micro Circuit Breaker (MCB), abbreviated as MCB, is the most widely used terminal protection device in building electrical terminal distribution equipment. Used for short circuit, overload, overvoltage and other protection of single-phase and three-phase below 125A, including four types: single pole 1P, two pole 2P, three pole 3P, four pole 4P, etc
A circuit breaker refers to a mechanical switchgear that can connect, carry, and disconnect current under normal circuit conditions, as well as connect, carry, and disconnect current for a certain period of time under specified abnormal circuit conditions.
A miniature circuit breaker consists of an operating mechanism, contacts, protective devices (various release devices), arc extinguishing system, etc. Its main contact is manually operated or electrically closed. After the main contact is closed, the free release mechanism locks the main contact in the closed position. The coil of the overcurrent release and the thermal element of the thermal release are connected in series with the main circuit, while the coil of the undervoltage release is connected in parallel with the power supply. When a short circuit or severe overload occurs in the circuit, the armature of the overcurrent release will engage, causing the free release mechanism to operate and the main contact to disconnect the main circuit. When the circuit is overloaded, the thermal element of the thermal release generates heat, causing the bimetallic strip to bend and pushing the free release mechanism to move. When the circuit is under voltage, the armature of the undervoltage release is released. Also make the free release mechanism operate