避雷器是一种能释放雷电或兼能释放电力系统操作过电压能量，保护电工设备免受瞬时过电压危害，又能截断续流，不致引起系统接地短路的电器装置，是连接在导线和地之间的一种防止雷击的设备，通常与被保护设备并联。
Lightning arrester is a kind of energy release and energy release lightning or power system over-voltage protection equipment from electrical energy, instantaneous overvoltage, and truncation wheeling, causing short-circuit electrical device is connected to the device to prevent lightning strikes between the wires and the one, and usually protected parallel device.
避雷器可以有效的保护电力设备，一旦出现不正常电压，避雷器产生作用，起到保护作用,当电压值正常后，避雷器又迅速恢复原状，以保证系统正常供电。
The lightning arrester can effectively protect the power equipment. Once the abnormal voltage appears, the lightning arrester will play a protective role. When the voltage is normal, the lightning arrester will return to its original state quickly, so as to ensure the normal power supply of the system.