DC Voltmeter: 0-200V. Power supply: DC4-30V Measuring range: 0-200V. Measurement accuracy: ±0.1% Refresh rate: about 200ms Display: 0.56 “digital tube Color: red, DC Voltmeter: 0-30V. Power supply: DC4-30V Measuring range: 0-30V. Measurement accuracy: ±0.1% Refresh rate: about 200ms Display: 0.56 “digital tube Color: Red Operating current: Less than 8mA Operating temperature: -10°C to 65°C Input impedance:100K Overall dimension: 48*29*26mm Display LED color – Red Wiring instructions: White Line: Measuring DC 0-30V Red line: Power Supply DC 4-30V Black lines: Common negative Range DC 0-30V, 3-wire products Universal, to break the routine voltmeter, is the latest design, can work directly in 5V, 9V, 12V, 24V and other circuits, without regulation. With three wiring, easy access to car /battery car / motorcycle-car line, with reverse polarity protection, line reversal will not burn. For monitoring the battery voltage, battery voltage state to grasp, it can also be used for other products voltage measurement purposes.