The Model 201A is an auto-ranging voltage monitor designed to protect 3-phase motors regardless of size. It is used on 190-480VAC, 50 or 60Hz motors to prevent damage caused by incoming power problems.

A unique microcontroller-based voltage and phase-sensing circuit constantly monitors the 3-phase voltages to detect harmful power line conditions. When a harmful condition is detected, the MotorSaver's output relay is deactivated after a specified trip delay. The output relay reactivates after power line conditions return to acceptable levels. The Model 201A includes advanced single LED diagnostics. Five different light patterns distinguish between faults and normal conditions.