... protector for ac power 2.working voltage: 220V /380V AC 3.1,2,3,4P(+NPE) 4.ISO9001 5.8 years experience ... . Third level protection2. install in the frond of the equipment 3. limit the overvoltage under the equipment’s overvoltage resistance level ... -in modular design, easy installation, simple maintenance, module degradation indication, automatic switching off at exit failure and recovery, do not affect ...