Microcontroller-Operated pH and EC Reader
Ferhat Ozdemir, Abdulhamid Zaidi, Vajih Khan, Iftekhar Ibne Basith · Zenodo (CERN European Organization for Nuclear Research) · 2023
The Microcontroller-operated pH (potential of Hydrogen) and EC (electrical conductivity) reader modules monitor and control the pH and EC of water to create a suitable environment for crop irrigation in a hydroponic system. The prototype module implemented in this study improved the stability of the water’s pH and EC levels and should ensure long-term usage with minimum maintenance. The modules’ microcontroller can support multiple communication protocols to communicate with other devices for long-distance data transmission. With the addition of ProfiNet/ProfiBus/EthernetIP modules, the modules can support communication with PLCs. A pH sensor acted as a voltmeter and measured the voltage at milli-volt (mV) level. The pH sensor’s voltage range was between -414 mV and 414 mV; this range was low enough to have interfered with electromagnetic interference (EMI). The length of the sensor cable needed to be kept as short as possible at the pH reading circuit for an accurate reading. The analog portion of the pH modules read the sensors and amplified the output, then sent it to the microcontroller to process. The microcontroller read the analog value and provided calculations for the pH scale. Also, the microcontroller allows users to perform digital calibration.