Unstable PH measurement
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The ABB pH meter gives unstable pH readings for pure water, with poor accuracy; however, its readings for standard solutions are basically accurate! Help, please!
This post was last edited by qugd on 2016-11-2 at 18:22. Pure water cannot be measured using a regular pH meter; it is necessary to use a pH electrode designed for pure water, along with a flow cell suitable for pure water, in order to conduct measurements. Additionally, for some quality parameters of pure water, sampling for measurement is not suitable; online analysis methods should be used, along with appropriate probes and flow cells for pure water analysis. For issues with online analyzers, it’s best to post in the analysis section, as that way more people will be able to see the post. Analyze the connections of the section: http://bbs.hcbbs.com/forum-224-1.html
I have a reaction vessel to which pure water is added, and the pH is measured; however, the readings are inaccurate every time. The result remains incorrect even after adding acid or base, and an ABB TH82 pH meter is being used
No way, I’m just going to explain the situation; I have no idea what to do
During calibration, the measurement is taken over a short period of time, which is not sufficient to determine the true condition of the pH meter; it is necessary to observe over a longer period. Trying a new probe could also be an option.
Check whether the header grounding is good. I also experienced large deviations here before.
For pure water, an internally pressurized pH electrode should be used
Does the ABB pH model not come with a pressurized salt tank? This type of measurement of EH is where Mettler excels. Pure water has a very low conductivity, which means the electrolyte is used up quite quickly and must be replenished constantly; therefore, there is usually an electrolyte tank installed that allows for continuous addition of electrolyte, just like in an intravenous infusion. .