What to look for when using PH meter/acid meter electrodes
1. Before the next operation after each calibration and measurement, the electrode should be cleaned with distilled or deionised water, and then cleaned once more with the measured liquid.
2. When removing the PH meter/acid meter electrode sheath, the sensitive glass bubble of the electrode should be avoided from contacting with hard objects, because any breakage or rubbing of hairs will make the electrode ineffective.
2. The end of the measurement, timely PH meter / acidity meter electrode protective sleeve on the electrode sleeve should be put a small amount of saturated KCL liquid to keep the electrode bubble wet, do not soak in distilled water.
4.PH meter / acidity meter composite electrode external reference supplement for 3 mol / L potassium chloride solution, the supplement can be added from the electrode on the end of the small hole, composite electrode is not in use, covered with a rubber stopper, to prevent the supplement from drying out.
5. PH meter / acidity meter electrode must be kept clean and dry at the end of the lead, absolutely prevent the output of the two short-circuit, otherwise it will lead to the measurement of inaccuracy or failure.
6.PH meter / acidity meter electrode should be matched with a higher input impedance pH meter ≥ 3 × 1011Ω, in order to maintain its good characteristics.
7.PH meter / acidity meter electrode should be avoided for a long time immersed in distilled water, protein solutions and acidic fluoride solutions.
8. PH meter / acidity meter electrode to avoid contact with silicone oil.
9. PH meter / acidity meter electrode after long-term use, such as the slope is found to be slightly reduced, the electrode can be immersed in the lower end of the 4% HF hydrofluoric acid (3-5) s, washed with distilled water, and then immersed in 0.1 mol / L hydrochloric acid solution, so that it is new, it is best to replace the electrode.
10. If the measured solution contains sensitive bulb easily contaminated or blocked liquid junction of the material and make the electrode passivation, there will be a reduction in the slope, the display readings are not allowed to phenomenon. If the phenomenon occurs, it should be based on the nature of the contaminant, with the appropriate solution cleaning, so that the electrode new.
Note 1: When selecting cleaning agent, carbon tetrachloride, trichloroethylene, tetrahydrofuran and other cleaning solutions that can dissolve polycarbonate resin can not be used, because the PH meter/acidometer electrode shell is made of polycarbonate resin, which is very easy to contaminate the sensitive glass bulb after dissolution, thus making the PH meter/acidometer electrode ineffective. Neither can you use the composite electrode to measure the above solution. At this time, please use the glass shell PH meter / acidity meter composite electrode.
Note 2: PH meter / acidity meter composite electrode use, the most likely problem is the external reference electrode of the liquid junction, the liquid junction of the blockage is the main cause of error.
