Description: It provide 5 kinds of functions for users to choose, to meet more application needs. You can set the voltage upper and lower voltage limits. Measuring range 0-100V DC, measuring accuracy ±0.1V. You can set the automatic power saving function. All set parameters can be automatically saved, the setting contents won't be lost when blackout occurs. Specification: Working voltage: DC 5V, 12V, 24V (nominal voltage should not exceed ±10%). Size(L×W×H): Approx. 67×44×20mm/ 2.64×1.73×0.79 inch Module voltage inputs: a 4-wire interface, all the terminals are the interface. DC+: DC power positive DC-: DC power supply negative V+: measuring voltage positive electrode V-: measure negative voltage 5 types of function: 1. Voltage measurement: select this function, the relay will not move, the digital display of the current measurement voltage; 2. Charging monitoring: When the measured voltage is lower than the lower limit voltage, the relay pulls above the upper limit voltage, the relay is disconnected; 3. Discharge monitoring: When the measured voltage is higher than the upper limit voltage, the relay pulls, below the lower limit voltage, the relay is disconnected; 4. Interval within the pull: When the measured voltage between the upper and lower limits, the relay pull, the other case the relay is off; 5. Interval outside the pull: When the measured voltage is lower than the lower limit voltage, or the measured voltage is higher than the upper limit voltage, the relay pull; other circumstances the relay is disconnected. Package Includes:(2 Pack) 1 Piece of DVB01 Digital Display Voltage Measuring Module