a. Please confirm that the storage status of the electrode before use meets the requirements of "electrode storage". If the electrode is not properly stored, please immerse it in a 3mol/L potassium chloride solution for more than 2 hours.

b. Please check if the electrode performance is qualified: Set the instrument display mode to mV, immerse the electrodes in standard buffer solutions of pH 4.00 and pH 9.18, and record the values displayed by the acidity meter. The absolute sum of the values should be greater than 292mv.

c. For electrodes with unsatisfactory performance, you can try cleaning the electrodes.