Voltage Detection Sensor Module 25V module is based on the principle of resistive voltage divider design, it can make the red terminal connector input voltage to 5 times smaller.Arduino analog input voltages up to 5 v. The voltage detection module input voltage not greater than 5Vx5=25V (if using 3.3V systems, input voltage not greater than 3.3Vx5=16.5V).
It has the limit of Arduino analog input 5 VDC only. So if you wish to measure higher voltages, you will need to resort to another means. One way is to use a voltage divider. The one discussed here is found all over Amazon and eBay. It is fundamentally a 5:1 voltage divider using a 30K and a 7.5K Ohm resistor.
Note:Ā Keep in mind, you are restricted to voltages that are less than 25 volts. More than that and you will exceed the voltage limit of your Arduino input.