Installation of short circuit protection device and installation method

1 in order to prevent the distribution of the wire and cable from overheating and failure, should be in excess of the current carrying capacity of the line when the fault line. Therefore, all lighting distribution lines should be equipped with short circuit protection device. In addition to short circuit protection, there shall be an overload protection device for residential, important public buildings and warehouses, and other lighting and distribution lines with explosive and fire hazard. Nowadays, the low voltage circuit breaker is widely used in the lighting circuit, and the circuit breaker has short circuit protection and overload protection. The circuit breaker is provided with a protective device for preventing overload, and the action is fast and reliable, which can reduce various risks.

2 for the frequent operation of the circuit and equipment, should be used as a contactor switch electrical appliances, in front of the contactor with a knife switch as an isolating switch, and then fuse and thermal relay as a protection. In the case of higher requirements, it is often used as a low-voltage circuit breaker protection and under voltage protection, thermal relay as overload protection, and the contactor as a switching device.

3 in the lighting circuit, rated current switch, contactor, socket, usually in about 1 - 1.3 times the current line selection, and the rated current of thermal relay is the working current of line 1 should be 1.1 times the.

Should be used as a switch contactor