Abstract: The present invention provides a switching circuit for the master-slave feeding mode of the low voltage power supply. The switching circuit utilizes the active switches as the switching devices, so that it can increase the switching speed, decrease the voltage drop and loss, being suitable to the low voltage circuits, and can judge or determine the master power supply and the back-up power supply, realizing the switching between the master and slave power supplies without interruption. The switching circuit of the invention improves the reliability of the system and has the simple structure and easy operation.

Abstract: An outdoor lightning protection power supply system comprises an AC distribution plant, an AC/DC rectifier and a backup battery, wherein a lightning protection system, a main earthing bar as well as a filter for absorbing AC load conducted interference is provided at the input terminal of the AC distribution plant, and there is provided an electrical box for accommodating them. Take the system lightning protection, the system earthing and the system filtering, as well as the system power supply into consolidated consideration, the present invention not only has the advantage of small volume and integration convenience, but also improves the reliability of the power supply system. Since the integration of the system is significantly improved, the number of the lightning protection module can be reduced, whereby reducing the system cost and saving the available space of the outdoor communication cabinet.

Abstract: The present invention provides a switching circuit for the master-slave feeding mode of the low voltage power supply. The switching circuit utilizes the active switches as the switching devices, so that it can increase the switching speed, decrease the voltage drop and loss, being suitable to the low voltage circuits, and can judge or determine the master power supply and the back-up power supply, realizing the switching between the master and slave power supplies without interruption. The switching circuit of the invention improves the reliability of the system and has the simple structure and easy operation.