Small circuit breakers are used in various electrical applications, and they are installed in every household, whether in the industrial or communication industriesFunction of miniature circuit breakerWhat are there? Let's walk into Wei Kewei and communicate with their FAE to see how they explain it?

1. Choose based on the purpose of use and the location of the electrical equipment

The residual current circuit breaker is used to prevent personal electric shock, and should be selected according to the different requirements of direct contact and indirect contact electric shock protection.

1) Protection against direct contact with electric shock

Due to the significant harm caused by direct contact with electric shock and the serious consequences, it is necessary to use highly sensitive residual current circuit breakers. For electric tools, mobile electrical equipment, and temporary circuits, residual current circuit breakers with an operating current of 30mA and an operating time of within 0.1s should be installed in the circuit. For residential buildings with a large number of household appliances, it is best to install them after the entrance energy meter. If electric shock is likely to cause secondary injury (such as high-altitude operations), a residual current circuit breaker with an operating current of 15mA and an operating time within US should be installed in the circuit. For electrical medical equipment in hospitals, residual current circuit breakers with an operating current of 6mA and an operating time within US should be installed.

2) Indirect contact electric shock protection

Indirect contact electric shock in different places can cause varying degrees of harm to people, so different residual current circuit breakers should be installed in different places. For places with high risk of electric shock, it is required to use leakage circuit breakers with high sensitivity. The risk of electric shock is much higher in damp places than in dry places. Generally, a residual current circuit breaker with an operating current of 15-30mA and an operating time of less than 0.1s should be installed. For electrical equipment in water, a residual current circuit breaker with a current of 6-10mA and an operating time within US should be installed. For electrical equipment that operators must stand on metal objects or inside metal containers, as long as the voltage is higher than 24V, a residual current circuit breaker with an operating current of less than 15mA and an operating time within US should be installed. For fixed electrical equipment with a voltage of 220V or 380V, when the grounding resistance of the casing is below 500fZ, a single machine can install a residual current circuit breaker with an operating current of 30mA and an operating time within 0.19. For large electrical equipment with a rated current of over 100A or power supply circuits with multiple electrical devices, residual current circuit breakers with operating currents of 50-100mA can be installed. For electrical devices with grounding resistance below 1000, residual current circuit breakers with operating currents of 200-500mA can be installed.

After the circuit is connected, check if the wiring is correct. It can be checked through the test button. If the circuit breaker can disconnect correctly, it indicates that the leakage protector is installed correctly. Otherwise, the circuit should be checked and the fault should be eliminated. After the leakage protector is put into operation, after a certain period of time, the user should check whether the circuit breaker is running normally through the test button;.

02. The leakage, overload, and short-circuit protection characteristics of circuit breakers are set by the manufacturer and cannot be adjusted arbitrarily to avoid affecting performance; The function of the test button is to check the operating status of the circuit breaker when it is newly installed or running for a certain period of time, while it is closed and powered on. Press the test button, the circuit breaker can be disconnected, indicating normal operation and can continue to be used;

03. If the circuit breaker cannot be disconnected, it indicates that there is a fault in the circuit breaker or the line and maintenance is required;

04. If the circuit breaker breaks due to a fault (leakage, overload, or short circuit) in the protected circuit, the operating handle is in the release position (middle position). After identifying the cause and troubleshooting, the operating handle should be pulled downwards (i.e. placed in the "open" position) to make the operating mechanism "snap back" before performing the closing operation (please note the different meanings of the three positions of the circuit breaker operating handle);

After the circuit breaker is disconnected due to a short circuit in the circuit, the contacts need to be checked. If the main contacts are severely burned or have dents, maintenance is required;

06. The four pole residual current circuit breaker must be connected to the neutral line to ensure the normal operation of the electronic circuit;

07. The load wiring of the residual current circuit breaker must pass through the load end of the circuit breaker. It is not allowed for any phase or neutral line of the load to not pass through the residual current circuit breaker, otherwise it will cause artificial "leakage" and cause the circuit breaker to fail to close, resulting in "misoperation".

Weikewei's engineers are still very professional. They have compiled so much practical knowledge in such a short time. If there are similar technical issues in the future, our editor will continue to provide them to you. We welcome you to have in-depth and efficient communication and interaction with FAEs.