How often is a PH meter calibrated for erratic readings?
PH meter readings are inaccurate, acidity meter use how long to calibrate? Inaccurate readings can be found in two ways: PH electrode operation process and maintenance process.
PH meter electrode detailed analysis
1, whether the measurement before calibration; a calibration is not good, you can repeat the calibration, refer to the 3-point calibration of the Ziman instrument manual. "What should be done for the third point calibration of PH meter? ", really can not calibrate, consider changing the electrode.
2, the electrode bulb is contaminated, need to be reasonable cleaning: the measured solution, such as easy to contaminate the sensitive bulb or plug the liquid junction of the material and make the electrode passivation, there will be a reduction in the slope, display readings are not allowed to phenomenon. If this phenomenon occurs, the electrode should be cleaned with appropriate solution according to the nature of the contaminant to make the electrode new again. The cleaning procedure can be referred to the above official website.
3, the electrode is immersed in each measured solution before the application of distilled water to wash, and absorbent paper to carefully absorb the adherent liquid, so as not to contaminate and dilute the measured solution, resulting in measurement and analysis is not allowed.
Simplified analysis
1,PH meter probe has dirt, to clean.
2,Loose wiring
3, PH meter aging
4, the measured liquid fluctuations
The main reason is that the number of ions in the solution is too small, resulting in unstable readings, such as pure water, of course, there may also be a question of the instrument 1, the PH meter has not been cleaned, there is a residual reagent
2, the solution has a reaction in progress
3, the solution is not shaken well
Acid meter use how long to correct once here to distinguish between you are used in industry, or laboratory PH meter.
1, industrial use if it has been measuring the solution medium, then there is no need to calibrate, if it is from the original down, and then loaded back to be re-calibrated or calibrated.
2, laboratory use laboratory PH meter, the requirements of more accurate, of course, each time you do the experiment is not the same, so each time before use should be recalibrated once.
