Why does the air switch (molded case circuit breaker) burn up？

Friends often ask this question, but I don't know why the upper end of the air switch (referred to as circuit breaker) is burned out. Today I will tell you about the problem.

The front is caused by the wiring. Because the installer did not tighten the screws, the heating load caused the upper end to burn out.

The second is caused by wiring. In many cases, the circuit breaker is tightened during installation. The screws are loose due to transportation reasons, and the upper end screws of the wiring outlet will not be checked. Therefore, the upper end of the circuit breaker is burned out due to the loosening of the screws without pressure.

The third is that the insulation has not been handled properly. When installing the circuit breaker, we must pay attention to whether the copper bars of each phase are tied with insulating sleeves. If there is no insulating sleeve, due to the distance between the copper bars and the curved shape, it is also It is easy to cause the copper bar and the mounting bracket to be connected to electricity, resulting in a short circuit and burning out the break on the circuit breaker.

There is also whether the phases are separated by arc partitions. Under normal circumstances, it will not cause a short circuit between phases, but if the condensation phenomenon caused by high humidity leads to a short circuit between phases,

The fourth is high-altitude areas. Due to the thin air in high-altitude areas, the capacity of the product decreases. Under normal circumstances, the rated current below 2000 meters above sea level is no problem for full-load operation, but if you reach high-altitude areas, the circuit breaker must be expanded and used, depending on the altitude. height for expansion.