Review on 🔋 bayite Pack of 5 Three-Wire Calibratable DC 0~30V Red Digital Mini Voltmeter Gauge Tester: Reliable Car/Motorcycle Battery Monitor & Voltage Meter with 0.36" Red LED Display Panel by Thasapon Bowers

Wow, excellent quality: the voltmeter shows the exact value of the electrical potential in volts, it is small and easy to assemble in the project box, the connection is also simple: black is a regular "ground" connection. The red wire is needed to power the internal circuitry of the voltmeter. Internet data warns against operating the voltmeter from a source greater than 30 volts. The white wire is the connection of the measuring sensor. This is the wire that the voltmeter uses to get the reading it shows. The internal resistance of the sensor input is very high, indicating a FET input. The red and white leads can be connected to form a two-wire voltmeter with a maximum range of 30 volts. The online data differs on how high the potential that only the white wire input can handle.