How to use circuit breaker

- Nov 28, 2020-

How to use circuit breaker


Precautions for using circuit breaker:

1. The ambient temperature should not be too high, the standard temperature is 30℃, and the bimetallic sheet in high temperature environment is excessively bent, which may malfunction


2. The humidity should not be too high. Excessive humidity will oxidize the internal metal parts and reduce the insulation performance


3. The dust should not be too heavy, as the dust particles enter the inside and cause the mechanism to jam


4. The cross-sectional area of the connecting wire is appropriate, and the incoming and outgoing wires are firmly connected. The longer the wire used, the thinner the wire, the greater the internal resistance of the wire, and the greater the heat. After a certain period of time, the insulation sheath of the wire may melt due to overheating, causing a short circuit of the circuit or even a fire.


5. The electronic internal electronic components have a limited withstand voltage. Do not use a shaker to shake the insulation, use a multi meter to test the insulation resistance of the outlet end, with overvoltage protection, insulation resistance >6MΩ, without overvoltage protection, infinity


6. The power cord is connected from the upper end (the upper line enters the lower line)

Hwo to use circuit breaker

Recommended value of conductor cross-sectional area under different current

Rated current (A)61016-202532-405063
Conductor cross-sectional area (mm2)11-1.51.5-2.52.5-44-66-86-10


Selection principle:

Lighting circuit 10A---16A (without leakage)

Air conditioning circuit 16A-25A (without leakage)

Socket circuit 16A—32A (with leakage current)

Main switch 32A—63A (without leakage current)


Misunderstanding of using circuit breaker

1. It must act to reach the rated current

2. Short circuit conditions must act

3. It's OK to go up and down

4. Leakage circuit breaker must act when thunder

5. Leakage circuit breaker must act when people get an electric shock