Function: 1.This relay can monitor your own working voltage (true RMS measurement). 2.8 adjustable rated voltage 3. The voltage measurement accuracy is less than 1%. 4. The working condition of the relay is indicated by the LED indicator. 5. Super small, this relay can be attached to a 35mm DIN rail. 6. Application: Protection and control equipment (tower crane, elevator, agricultural equipment, refrigerated truck). Protects your device from reverse riding Normal/Emergency Power Switch; Protects against Dynamic Load Phase Failure Specifications: Functions: Monitoring L-L voltage (3-phase 3-wire system); Surveillance terminal: L1-L2 power: L1-L2 rated operating voltage: 220-230-240-380-400-415-440-460 (P-P); Rated power frequency: 45Hz - 65Hz Measurement range: 1 V voltage. Threshold Range: 2%-20% (rated voltage)Voltage fixed lug ratio: 2% Voltage measurement error: ≤1% Power on delay time: 0.5 second knob setting accuracy: 10% Reset time: 1 second temperature fluctuation error: 0.05%/°C, at = 20°C Output: 1 x SPDT; 10A/AC1; 250VAC/24VDC Minimum Switching Power: 50VDC 0 mW Over Voltage: 2%-20% Low Voltage: -20%-2% Action Delay Time: 0.1-10 seconds Adjustable Phase Sequence Protection: Yes Power Indicator: Green LED Output Relay Display: Red LED Mechanical Life: 1 x 107 Installation Method: 35mm DIN Rail Mounting Altitude: ≤2000m Weight: Approx. 78g/2.7oz Package List: 1 x Voltage monitoring relay