Varistors are common circuit protection components and are widely used in various switching circuits. The lightning protection varistor is an essential protection component for products such as high-power power supplies. Lightning varistor, its main job is to protect electrical appliances during thunderstorms.
The working principle of the varistor is in parallel with the electric appliance in the circuit. When the electric appliance is working normally, since it has a large electric resistance, it basically does not work. When a large current flows in the circuit, the lightning protection varistor is turned on instantaneously, and the current in the circuit flows through the lightning protection varistor, thereby protecting the electrical appliance. lightning protection Zhixu Xiaobian introduces the application of lightning protection varistor: TV varistor lightning protection.
Thunderstorms watch TV programs, and their lightning can be broken into the TV through two channels: one is through the outdoor TV antenna; the other is through the TV's power cord. The former often damages the high frequency head, which often damages the power supply circuit and the field output circuit of the television. Adding a varistor to the outdoor antenna can suppress this kind of evil, requiring the varistor to directly connect to the ground. Protect the application circuit of the power supply section. They are generally anti-inductive lightning. If they hit a direct lightning strike, the varistor is powerless in view of the huge current and extra high voltage of the direct lightning strike. Therefore, the lightning protection device should be placed around the outdoor antenna. The installation position of the outdoor antenna should be Protection zone of lightning protection device
Because the protection level of different types of lightning protection varistor is different, engineers must choose the type of lightning protection varistor according to the design requirements of the equipment. Professional lightning protection varistor manufacturers can provide you with varistor selection advice. Generally, the two types of nominal varistor voltage V1mA and flow capacity are used as reference.