_x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ Wiring instructions: As a two-wire meter application, please send a short circuit board R1, connected to the inputs of the input voltage can be displayed. (When using two-wire measuring range do not exceed 30V) As a three-line header using the R1 plate off the table, the ground and power supply voltage connection 4-30V power supply for the header. Indirect ground voltage to be measured and the test voltage input. (Two to the board pads is the same, can according to the actual wiring by one or two will do) Adjust panel potentiometer can display the value of prospective effect. 5PIN pin for the expansion of output, K1, K2 for the onboard external key switch lead, as do key-board, the two PIN via an external button, the button functions with the same function button panel. LV as the lower limit alarm output, output low when below the set value. HV upper limit alarm output, the output is higher than the upper limit set at the low value. LV, HV outputs a control signal for driving the driver circuit, please add lights, or relay other loads. Upper and lower limit setting method: two keys are pressed, the red light (HV) is lit, press the + or - key to set the desired alarm limit voltage value. And then pressing both buttons simultaneously, yellow (LV) is lit, press the + or - key to set the lower limit alarm voltage required. And then pressing both buttons simultaneously to exit the setting. Supply voltage: 4-30V Measuring range: 0-100V Upper/Lower limit setting range: 0.1-99.9V Upper/Lower limit output mode: on set range will output high level,otherwise output low level. Minimum resolution: 0.1V Refresh rate: 300mS/times Operating temperature: -40 to +85 Input reverse polarity protection: YES Installation: 2pcs 2mm screws Size: 29x23x10mm(LxWxH) Applications: DIY power supply, as the voltage display. Voltage monitoring. The device overvoltage or undervoltage alarm, or overvoltage or undervoltage protection. Battery over-discharge protection. To be more application you develop. Kindly Note: When applying two-wire, the measurement range and scope of supply is the same, so do not exceed 30V measurements. When measuring voltage exceeds 30V, with a three-wire! Colour: as shown Material: plastic+metal Package Contents: 1 * LED Digital Voltmeter Buzzer Alar Only the above package content, other products are not included. Note: Light shooting 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. _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_