Suppression circuit composed of gas discharge tube and varistor
The diagram is a surge suppression circuit composed of a gas discharge tube and a varistor. As the varistor has a fatal flaw: the leakage current is stable, the varistor poor performance after a period of time, due to leakage current increases may heat up. In order to solve this problem, a gas discharge tube is connected between varistors. But the disadvantage is that the reaction time is the sum of the reaction time of each device. For example, the reaction time of varistor is 25ns, the reaction time of gas discharge tube is 100ns, then the reaction time of R2, G and R3 of the diagram is 150ns, and the R1 varistor is added to improve the reaction time, so that the reaction time is 25ns.