Littelfuse 102A2, 3-Phase Voltage Monitor/ 190-4

The 102A series is a three-phase, auto-ranging, dual-range voltage monitor that protects 190–600 V ac, 50*/60 Hz motors regardless of size. This monitor provides a user-selectable nominal voltage setpoint and will automatically select between the 200 V and 400 V range. A unique microcontroller-based voltage and phase-sensing circuit constantly monitors the three-phase voltages to detect harmful power line conditions. When a harmful condition is detected, the output relay is deactivated after a specified trip delay. The output relay reactivates after power line conditions return to acceptable levels. The 102A monitor includes advanced, single LED diagnostics with five different light patterns that distinguish between faults and normal conditions. LED indications include normal operation, power-up restart delay, reverse-phase trip, unbalance/single-phase trip, and high- or low-voltage trip.