1.Over-voltage protection 2.Under-voltage protection 3.Over-current protection 4.Automatic recovery 5.Voltage display(voltage measurement) 6.Current display (current measurement) 7.Wattmeter kWh Energy Meter Power Consumption 8.Installation:35mm DIN rail Rated supply voltage:AC 220V Operation volatge:AC 80-400V(single phase) Rated frequency:50/60HZ Kilowatt-hour protection value:1-9999/OFF Rated current:40A(subject to product label) Reset /start delay time:1-600s Voltage measurement accuracy:2%(not exceeding 2% of the overall range) Rated insulation voltage:400V Output contact:1NO Electrical life:100000 Mechanical life:1000000 Protection degree:IP20 Pollution degree:3 Operating temperature:-50-55 Humidity:50% at 40 (without condensation) Storage temperature:-30-70 Colour:As Shown Material:plastic Package Contents: 1 x Adjust Voltage Relay Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.