Why Should Working Voltage Be Considered for Varistor

The circuits of current electronic products are delicate and complex, and many aspects need to be considered in the selection of electronic components used in circuit protection. The varistor is a voltage-limiting protection component.

When the voltage at both ends of the varistor in the circuit is too large, the varistor will clamp the voltage, control the circuit voltage within the acceptable range, and also absorb excess current to prevent the circuit from burning and protect other components.

In the circuit system, the varistor plays an overvoltage protection role, and the overvoltage protection of the varistor can increase the stability of the entire system. When working, the varistor may sometimes sparkles, especially for the varistor connected to the power line, which is a very bad phenomenon.

The change of the varistor when the working voltage is different:

(1) When the voltage applied to the varistor is lower than its nominal value, the resistance of the resistor is infinite, and almost no current flows through;

(2) When the voltage across the varistor is slightly greater than the nominal voltage, the varistor quickly breaks down and conducts, and the resistance decreases, making the resistor in a conducting state and the current flowing through the varistor;

(3) When the voltage applied to both ends of the varistor is far beyond the limit voltage range, the varistor cannot prevent the current from passing through, and the voltage is too large to break down the varistor and damage the varistor. The damage to the varistor is irreversible

Therefore, when selecting a varistor, the appropriate model should be selected according to the working voltage, and the voltage applied to the varistor should not be higher than the nominal voltage of the varistor. If you don’t know how to choose a varistor model, you can consult a professional in the industry.
JYH HSU(JEC) Electronics Ltd (or Dongguan Zhixu Electronic Co., Ltd.) is one of largest manufacturers in China in terms of yearly safety capacitor (X2, Y1, Y2) production. Our factories are ISO 9000 and ISO 14000 certified. If you’re looking for electronic components, welcome to contact us.