Specification:Model: JVR 800-2Monitoring Circuit: L1, L2, L3Rated voltage: 208-480V AC, 50/60HzProtection: over-voltage, under-voltage, voltage unbalance, phase loss, phase sequence, counterOvervoltage setting range: 200-600VUndervoltage setting range: 150-500VVoltage hysteresis: 1-20VDelay time for overvoltage and undervoltage: 0.1-30sVoltage unbalance ratio: 1-50%Voltage unbalance hysteresis: 1-10%Voltage unbalance delay time: 0.1-30sDelay time for phase loss: 0.1-30sDelay time for phase sequence: 0.1-30sStart delay time: 0-999sAuto reset mode: ON/OFFAuto reset time: 0.1-999sTimer and counter input: AC/DC 80-450VIndicators: LCD indicating voltage,current,operation statusOutput contacts: 1 C/O,1NCContact capacity: 6A ,250VACDimensions (H*W*D): 80*43*54mm/3.15*1.69*2.12inchMounting: suitable for 35mm railWeight: 129g Features: Three phase voltage protector, chronograph and counter are integrated into one relay. It is equipped with protective functions for over-voltage, under-voltage, loss of phase, phase sequence and unbalanced three phase voltage. No external power requires. With useful functions: electricity delay, output test, etc. The LCD can show the data for easy reading. 2 rest module optional, manual and automatic.