dc-100v digital voltmeter 3-cable 0.36 inch 3-digit led red light

This is the 2-wire version of the volt meter, two wires are used to power it and measure at the same time. Connect the red wire to the positive supply, and black to negative ground. The microcontroller display will read the voltage, compare it to a stable reference and display the voltage with 0.1V precision on a 3-digit 7-segment display.