The characteristic of the varistor is that when the voltage applied to it is lower than its threshold "Un", the current flowing through it is extremely small, which is equivalent to a closed valve. When the voltage exceeds Un, its resistance The value becomes smaller, so that the surge of current flowing through it has little effect on other circuits, thereby reducing the impact of overvoltage on subsequent sensitive circuits. Utilizing this function, it is possible to suppress the abnormal overvoltage that often occurs in the circuit and protect the circuit from damage caused by overvoltage.

Varistors detect and suppress repeated voltage surges without damage. SPD varistor manufacturers believe that in summer, low-voltage electrical appliances in most parts of southern my country are damaged by lightning strikes, which not only cause heavy property losses, but also cause personal injury. Due to its special electrical characteristics, varistors can be used to manufacture various semiconductor devices to protect electronic equipment and lightning surge protection under overvoltage conditions, and to ensure the normal operation of various low-voltage devices under lightning strikes.

Application

1. Varistor voltage: refers to the voltage value across the varistor at a specified temperature and DC (generally 1mA or 0.1mA). Recorded as V1mA or V0.1mAo
2. Maximum continuous voltage: refers to the maximum effective value of sinusoidal AC voltage or the maximum DC voltage value that can be continuously applied to both ends of the varistor for a long time under the specified ambient temperature
3. Limiting voltage: refers to the maximum peak voltage at both ends of the varistor when a specified surge current (8,20μs) passes through it.
4. Rated power: refers to the maximum average impact power that can be applied to the varistor under the specified ambient temperature.
5. Maximum energy: the maximum impact energy that can be applied to the varistor under the condition that the varistor voltage does not change more than ±10% and the impulse current waveform is 10, 1000μs or 2ms.
6. Current capacity (maximum inrush current)