Features:_x000D_ 1. Monitor the working voltage (true RMS measurement)._x000D_ 2. The operating mode can be selected via the rotary knob._x000D_ 3. High accuracy, voltage measurement accuracy is 1%._x000D_ 4. The working status of the relay is indicated by the LED indicator, which is simple and convenient._x000D_ 5. Compact size, only 18mm width, 35mm rail mounting._x000D_ 6. Apply to over voltage protection for electrical equipment or compressors, emergency/backup power switching control._x000D_ _x000D_ Specification:_x000D_ Function Voltage monitoring _x000D_ Power terminal (monitoring terminal) A1-A2_x000D_ Rated power supply voltage (Optional) #1: AC220V _x000D_ #2: DC12V _x000D_ #3: AC/DC24V-48V _x000D_ #4: AC/DC110V-240V _x000D_ Rated power frequency 45Hz-65Hz _x000D_ Rated insulation voltage 460V _x000D_ Hysteresis value 5%-20% _x000D_ Power indicator Green LED _x000D_ Output relay indication Red LED _x000D_ Action delay time 0.1s-10s, 10% _x000D_ Voltage measurement error 1% _x000D_ Power-on delay time 0.5s _x000D_ Knob setting accuracy 1% _x000D_ Reset time 1s _x000D_ Temperature fluctuation error 0.05%/C, at=20C _x000D_ Output 1 * SPDT _x000D_ 10A/AC1 _x000D_ 250VAC / 24VDC _x000D_ Minimum switching power 500mW _x000D_ Mechanical life 1 * 10000000 _x000D_ Electrical life (resistive load) 1 * 1000000 _x000D_ Working environment temperature -20C- +55C _x000D_ Storage and transportation ambient temperature -35C- +75C _x000D_ Installation method 35mm rail installation _x000D_ Protection level IP20 _x000D_ Installation location Any _x000D_ Installation altitude 2000m _x000D_ Pollution degree 2 _x000D_ Wiring ability 1 * 2.5mm2 or 2 * 1.5mm2 _x000D_ Dimensions 90mm * 18mm * 64mm / 3.5 * 0.7 * 2.5in (Approx.) _x000D_ Standard GB14048.5 _x000D_ IEC/EN 60225-1 _x000D_ _x000D_ _x000D_ Package list:_x000D_ 1 * Relay_x000D_ 1 * User manual