How to Test the Quality of Surge Protector by Simple Method

Surge protectors are divided into switch type and voltage limiting type. Whether it is switch type or voltage limiting type surge protector, it can be measured with 220VAC(L-N) and 380VAC(L-L). The test of switching surge protector is based on the difference of voltage change rate. In principle, 380VAC changes faster than 220VAC, and the discharge time of surge protector is different at the same time. When tested at 380VAC, the surge protector discharged obviously, so the resistance measured at 380VAC was lower than that measured at 220VAC. The higher the voltage of voltage-limiting surge protector, the more obvious the discharge effect of metal oxide rheostat (MOV material, voltage-limiting type), and the resistance measured at 380VAC is lower than that measured at 220VAC. Of course, the resistance value of surge protector (tens of thousands of ohms to hundreds of thousands of ohms) should be measured by multimeter in advance.