How often should the ph electrode of the online water quality detector be calibrated?

pH is one of the routine measurement parameters of online water quality detectors. The current status of water quality can be understood through the change of pH value. Everyone knows that the pH electrode needs to be calibrated before use. But how often do you need to calibrate during use? Today we will learn something about the calibration of the pH electrode of the online water quality detector. How often should the pH electrode be calibrated? Everyone needs to know that there is no fixed schedule for recalibration, so if you are not sure whether your pH electrode needs to be recalibrated, there is an easy method you can try! Dip the pH electrode of the online water quality detector into the into the pH standard calibration solution (4.0, 7.0, 10.0). If the error of the measured buffer solution is within 0.05pH, no recalibration is required. If the error is large, recalibration is required. There are also online water quality detectors that measure the pH of water in aquaculture, hydroponic systems, or other environments that usually have weak acid-base levels, and only need to be calibrated once a year for the first two years of use, and then every six months. One time is enough, and you can also refer to the product instructions for specific details. In high precision environments, such as pharmaceutical manufacturing in laboratories, industrial waste disposal, or other applications known to have strong acids or bases, calibration in extremely acidic or alkaline solutions is recommended monthly or after each use. How to calibrate the pH electrode When calibrating the pH electrode, it is necessary to select the appropriate buffer solution according to the type of pH electrode used. The steps are as follows: First, turn on the pH electrode. After preparing the buffer solution, put it into the deionized water in the glass/beaker, rinse the pH electrode in the water, and let it dry. Drop the pH electrode into the first buffer solution (buffer solution with pH 7.0 is used), and continue to stir until the pH value is stable. Note the pH and the pH buffer solution used. To clean the pH electrode, repeat with at least one more buffer and remember to rinse with deionized water between dips. Clean the pH electrode after use and store it properly to avoid damage. Which buffer solution to use to calibrate the pH meter We can use the standard buffer solution to display the correct pH value to ensure the measurement accuracy of the pH electrode of the online water quality detector. Generally, 3 kinds of buffer solutions are required to calibrate the pH meter: pH4.0, pH7.0 and pH10.0. Before starting, use a pH 7.0 buffer solution to obtain an offset point. If the solution is in the acidic range (pH below 7.0), use a pH 7.0 buffer followed by a pH 4.0 solution for calibration. On the other hand, if you are operating in the alkaline range (pH greater than 7.0), you must use a buffer solution with a pH of 10.0, followed by calibration with a pH 7.0 solution. Precautions when using pH calibration buffer If it is a high-precision pH meter, a high-precision calibration solution is required. When calibrating the pH electrode with a different buffer solution, be careful not to contaminate the buffer solution. A small amount of buffer solution can be poured into a separate cup/container for calibration. The used buffer solution cannot be used again, and once exposed to the air, even if it has not been used, do not pour the buffer solution back into the original bottle.