This automatic over-voltage and under-voltage protector is designed for three-phase AC 380V, 50/60Hz systems with a rated working current of up to 63A. Its primary function is to instantaneously cut off power to connected equipment when the circuit experiences over-voltage or under-voltage conditions. The device will automatically restore power once the circuit voltage returns to the normal range. Color: Gray white. Material: PC plastic. Functions: Over-voltage protection, Under-voltage protection, Automatic operation, Voltage display (voltage measurement), Three-phase unbalance protection, Phase sequence protection (reverse phase protection), Break protection, Phase failure protection. Product Parameters: Model number: TOVPD3. Power supply: 3 x 230V / 400V AC 50/60Hz. Maximum load: 63A. Over-voltage protection range: 230V~300V adjustable (default: 270V). Over-voltage protection action time: 0.1~30 seconds (default: 1 second). Under-voltage protection range: 140V~210V adjustable (default: 170V). Under-voltage protection action time: 0.1~30 seconds (default: 1 second). Three-phase voltage unbalance protection range: 5-95V adjustable or OFF. Delay time after power-on: 1~500 seconds (default: 10 seconds). Installation: 35mm DIN rail. Package Contents: 1 x 3 Phase Voltage Relay. Condition: New.