Model 350 3-phase voltage monitor is perfect for heavy-duty applicationssuch as rural pump panels, commercial and rural HVAC equipment, and oilrigs. The Model 350 is a versatile voltage monitor designed for 200, 400, or600V applications. The Model 350-200 monitors 190 to 240V input voltages, the Model 350-400 monitors 380 to 480V input voltages, and theModel 350-600 monitors 475 to 600V input voltages.A unique microcontroller-based voltage and phase-sensing circuit constantly monitors the 3-phase voltage to detect harmful power line conditions such as single-phasing, low voltage, phase reversal, voltage unbalance, and high voltage (optional). When a harmful conditionis detected, the MotorSaver's output relay is deactivated after a specified trip delay. The output relay reactivates after power line conditions return to an acceptable level for a specified amount of time (restart delay).The trip delay prevents nuisance tripping due to rapidly fluctuating powerline conditions.The Model 350-400 and 350-600 are equipped with one standard 470VA@ 600V contact.The Model 350-400 and 350-600 can be ordered with 15Ageneral purpose contacts to switch heavier current loads.