DIGITAL MONITORING RELAY FOR 3-PHASE VOLTAGE WITH N-CONDUCTOR PHASE SEQUENCE CAN BE ACTIVATED PHASE FAILURE 3 X 160 TO 690 V 50 TO 60 HZ AC UNDERVOLTAGE AND OVERVOLTAGE 160-690 V HYSTERESIS 1-20 V OFF DELAY 0-20 S 2 CO FOR LINE SUPPLY FAULTS SCREW TERMINAL