1. Function: time-sharing switching of high voltage output circuit, switching of multi-way points of the tested part, safe discharge of high voltage at the end of the test, and gear switching; 2. Advantages: The insulation resistance in the open state can reach 10 ¹ 10 ~ 10 ² Ω, the leakage current is microampere level, and the insulation resistance and microampere level leakage can be accurately measured; the sealed contact will not produce open fire arc, which meets the requirements of explosion-proof and anti-ignition of safety equipment; 3. Adaptable voltage: mostly 1kV ~ 6kV, standard for withstand voltage test of wiring harness, household appliances and PCB.