The SLA Series is designed to protect three-phase equipment against Phase Loss, Under Voltage, and Phase Reversal conditions. With normal operating voltages applied in the proper ABC sequence, the internal relay will energize (PICK-UP). When incorrect phase sequence or phase loss occurs or the three-phase voltages fall below the drop out voltages, the relay will de-energize (DROP-OUT). Both Delta and Wye systems may be monitored. In Wye systems, connections to neutral are not required. For UL Listed units, with field wiring terminals, copper wire with 60° / 75°C rating must be used for control circuitry connections. On models featuring indicators, the LED glows when all line conditions are normal. NOTE: When a phase is lost while the motor is running, a condition known as regeneration occurs where a voltage is induced into the open phase nearly equal in magnitude to the normal phase-to-phase voltage. However, with the exception of lightly loaded motors, enough change is detected by the SLA to provide the required protection when properly adjusted.