PH sensors detect the presence of hydrogen ions in sample solutions to determine their pH level. A pH scale of 0 to 14 is used for this purpose, with 0 representing high acidity and 14 indicating high alkalinity. The neutral point on this scale is defined as a pH value of 7, which is equivalent to pure water. However, increasing the amount of base in water will cause its pH value to decrease.

In addition, PH Sensor PCB Type with Level and LDR includes a Light intensity sensor, Temperature sensor, and Water Level sensor. It is capable of measuring water level, temperature range, and light intensity.