Calibration Precautions of pH Meter
1. The laboratory needs more calibration times because experiments need to be conducted frequently and the solutions measured are different. At present, calibration methods are generally divided into one point, two-point calibration, and three-point calibration. The more calibration times, the higher the accuracy, and the more accurate the acidity meter measurement. For detailed calibration of points 1, 2, and 3, please refer to the technical articles on our official website for specific instructions.
2. When calibrating the instrument before measurement, a standard buffer solution that is close to the pH value of the test solution should be selected. After calibrating the instrument with a standard buffer solution during measurement, another standard buffer solution with a pH difference of about 3 should be used for verification, and the error should not exceed ± 0.1. Before each replacement of the standard buffer or test solution, the electrode of the acidity meter should be thoroughly washed with water, and then the water should be drained. Alternatively, the replaced standard buffer or test solution can be used for washing.
3. To calibrate the pH probe, two buffer solutions are sufficient. If the sample to be tested is acidic, please calibrate the probe with buffer solutions at pH 4 and 7. If the sample to be tested is alkaline, please calibrate with buffer solutions at pH 7 and 10. Buffer solutions are available in powdered form as granules and as finished solutions for sale. Granules have the advantages of long storage time and economy, but they are inconvenient. The finished solution is easy to use, but it is prone to spoilage after opening the lid. You can divide the finished solution into small beakers for use.
4. If you use powdered granules, please prepare a buffer solution with 50ml of deionized water before calibration. The buffer solution should be poured out after calibration. Therefore, the finished buffer solution should be divided and used separately. Never pour the used buffer back into the solution bottle.
