Publish Time: 2022-07-21 Origin: Site
Miniature circuit breakers are used for single-phase and three-phase short-circuit, overload, and overvoltage protection below 125A, including single-pole 1P, two-pole 2P, three-pole 3P, and four-pole 4P.
What are the working conditions of Miniature circuit breakers?
What should we pay attention to when choosing a Miniature circuit breaker?
What are the things we should notice for the use of Miniature circuit breakers?
1. The upper limit of the ambient air temperature of the Miniature circuit breaker shall not exceed +40℃, the lower limit shall not be lower than -5℃, and the average temperature value of 24 hours shall not exceed +35℃;
Note 1: When the lower limit is -10°C or -25°C, the user must declare to the manufacturer when ordering;
Note 2: When the upper limit exceeds +40℃ or the lower limit is lower than -25℃, the user should negotiate with the manufacturer.
2. The altitude of the installation site of the Miniature circuit breaker shall not exceed 2000m;
3. The relative humidity of the atmosphere does not exceed 50% when the ambient air temperature is +40°C, and higher relative humidity is allowed at lower temperatures, such as 90% at +20°C. Condensation should take appropriate measures;
4. Pollution level: 2;
5. Installation category: Class II and Class III;
6. The external magnetic field of the installation site should not exceed 5 times of the earth's magnetic field in any direction;
7. Generally installed vertically, with a tolerance of 2° in any direction;
8. There should be no significant shock and vibration at the installation site.
1) The selection of power distribution circuit breakers needs to consider the short-time delay short-circuit on-off capability and the coordination between delay protection levels;
2) The rated voltage of the undervoltage release of the Miniature circuit breaker is equal to the rated voltage of the line;
3) When used for motor protection, the selection of the circuit breaker should consider the starting current of the motor and make it not operate within the starting time;
4) The selection of Miniature circuit breakers should also consider the selective cooperation between circuit breakers and circuit breakers, circuit breakers and fuses.
1. After the circuit of the Miniature circuit breaker is connected, check whether the wiring is correct.
2. The leakage, overload and short-circuit protection characteristics of the Miniature circuit breaker are set by the manufacturer and cannot be adjusted arbitrarily.
3. If the Miniature circuit breaker cannot be disconnected, it means that the circuit breaker or circuit is faulty and needs to be repaired.
4. After the Miniature circuit breaker is disconnected due to the short circuit of the line, it is necessary to check the contacts.
There are many types of Miniature circuit breakers, and you should choose the right one according to your needs. And, we must consider its quality. Zhejiang Shilong Electric Technology Co., Ltd., as a Chinese pioneer in circuit breakers interconnects, can ensure the products’ quality and the after-sales service.