MCB and RCBO

Miniature circuit breakers (MCB) are mainly used for overload and short-circuit protection of electrical circuits;

In addition to the overload and short circuit protection of the miniature circuit breaker, the residual current circuit breaker (RCBO) also has the function of leakage protection.

The Role of Leakage Protection

The human body is prone to electric shock accidents after being exposed to voltage, and general electric shock deaths are mainly caused by the sudden stop of the heart. Since 30mA current is the threshold of ventricular fibrous movement, as long as the current flowing through the human body is less than this value, people will not die due to the occurrence of ventricular fibrous movement. Generally, the leakage current of the leakage circuit breaker selects 30mA as the protection action value.

Precautions for the Selection Of Circuit Breaker Rated Current

The overload and short circuit protection functions of miniature circuit breakers are mainly used to protect cables. According to GB 4706.1-2005 “General requirements for the safety of household and similar electrical appliances”, the requirements are made according to the load current corresponding to the current carrying capacity of the wire. The user can select the currency of the circuit breaker according to the cross-sectional area of the wire laying in the family residence.