Measuring and using method of precision acidity meter (PH meter)
1. Preparation before 1.PH meter measurement
1) Install the composite electrode on the electrode rod, and insert the electrode plug into the measuring electrode socket at the back of the instrument.
2) Connect the temperature sensor to the sensor socket (if it is set manually, it is unnecessary to connect the sensor).
3) Wash the electrode with distilled water.
2. Determination of electrode potential (mV)
Put the electrode in the solution to be measured, press the "mV" key, and the "mV" indicator will light up. Stir the solution evenly, and when the reading is stable, the displayed value is the electrode potential "mV" value of the solution, and the polarity is automatically displayed.
3. Because the zero potential conversion coefficient of each electrode is different from the theoretical value, and they are different. Therefore, in order to determine the pH value, the electrode must be calibrated.
1) Temperature setting. Press the "Temperature Setting" key to make the temperature indicator light at the temperature setting position. At this time, the display screen will flash. Use the → "key to move the setting position. At the same time, press the ↑" key to make the temperature display value be the temperature value of the measured standard solution at this time, and then press the "Confirm" key to confirm.
2) Wash the electrode with distilled water, blot it with filter paper, then put the electrode into a standard solution, press the "pH/pH Calibration" key to make the instrument in the pH measurement state, press the "pH/pH Calibration" key again after the reading is stable to make the instrument in the pH calibration state, and press the "→" and "↑" keys to make the displayed value be the pH value of the standard solution at the current temperature. Click the "Confirm" button again to confirm.
3) Wash the electrode with distilled water and blot it with filter paper. Put the electrode into a standard solution (select a standard solution with similar pH value according to whether the sample solution with pH value to be measured is acidic or alkaline, and its pH value is not more than 3 pH units from the * * standard solutions), press the "pH/pH Calibration" button to make the instrument in the pH measurement state, and then press the "→" and "↑" button when the reading is stable.
4) The instrument calibration is completed.
4. Determination of 4.pH value
1) After washing the electrode with distilled water, wash it with the tested solution for more than two times, and put the electrode in the tested solution.
2) Set the temperature according to the temperature setting method in pH calibration, so that the temperature value is the temperature of the tested sample at this time.
3) Press the "pH/pH Calibration" key to make the "pH" measurement indicator light on, and stir the solution with a glass rod to make it uniform. After the reading is stable, the displayed value is the pH value of the measured sample.
