... AC 50/60Hz 220V, 230V, 240V, 380V, 400V, 415V for overvoltage, undervoltage, phase failure, phase sequence, three phase asymmetry monitoring ... be used to protect single phase and two phase circuit. They are widely used for industrial control systems, capacitor of power ... can be used to protect single phase or two phase circuit.3. For PTC temperature protection functionand load side protection function ...