DROK® 0.40'' DC2.5-30V LED Waterproof Digital Voltmeter 12V/24V Voltage Meter Gauge Panel Battery Volt Monitor Tester with 2 Wires and Bright Red Digital Display for Solar Panel Lithium ion battery 18650 Monitoring

Parameters:
Measure range: DC 2.5-30.0V
Minimum input: DC 2.5V
Maximum input: DC 30V
Min input: DC 2.5V
Permissible Error: 1%; + / - 1 digit(its accuracy is 0.01V when in less than 10V and 0.1V when in more than 10V)
Display: three 0.40" LED digital tube
Refresh rate: about 200mS
Power supply: requires no extra power supply
Current consumption: about 5-20mA
Operating temperature: -10 °c ~ 65 °c
Dimensions: 40x25x23mm

Descriptions:
1.The volt meter adopts epoxy potting design; it is waterproof, anti-oil, moistureproof, shockproof and dust-proof
2.Connect the red wire to positive pole of measured voltage and black wire to negative pole of measured voltage
3.It requires low voltage to start working which is more convenient for lithium and 18650 battery users
4.Its digital point is moveable in accordance with your measured voltage; specifically, it will display two digits
after the decimal point when voltage is less than 10V and display one digit after the decimal point when volt is more
than 10V

Please Note:
Do not need power supply, can measure 2.5-30V directly
If the input voltage is below 3.5V, the display brightness dims
If the input voltage is below 2.5V,measuring inaccurate or no display
If measure 10V below, accurate to 0.01V,display x.xx
If measure 10V or more,accurate to 0.1V,display xx.x
Please don't use this meter in 24V battery because when the battery is full-charged, its voltage will be about 30V(the max input volt for this meter),
and we don't suggest you use it in max volt of 30V

Package Include:
1x Digital Voltmeter