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Pen pH meter care before storage.

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Borek:
I wonder if the wire you marked as a reference is not Ag covered with AgCl. If so, it had to be in a small chamber filled with chloride solution, and that would make perfect sense.

Or, it could be just a contact and the reference itself is built into the cap and covered with a glass frit.

How does the removed cap looks like from the inside? How was the wire attached/put into contact?

pH electrode itself looks like a more or less standard glass electrode.

xchcui:
I guess that i won't get a reliable answer,since from your answer,i see that you don't familiar with that type of ph meter.I did my best by sending a dismantle ph meter and also the manual,but if(with all my attachment)it doesn't help,i guess i leave it.
Anyway thanks alot for trying to help and for your replies :)
BTW,the remove cap has nothing special inside.

gedftsnd:
i would probably invest in a better pH meter

lucas.paula:
Perhaps this information is coming too late, even so:

This type of ph meter does not have a combined electrode. Thus, there are two separate electrodes on it: the working electrode (the glass sphere) which is with an Ag/AgCl wire filled with saturated KCl solution, concentration: 3M). And also the reference electrode which is exactly the one you marked in the figure, indicating it with a red arrow.

The reference electrode in this type of pH meter is a silver wire immersed in a POTASSIUM CHLORIDE GEL (3M KCl solution and 1 or 2% agarose). You can see that there is a little gel in which this thread was soaked. To avoid the passage of ions, what comes in contact with the sample to be analyzed is this small white "tube", which I don't know what would be the material of its composition.

It is difficult to extend the life of these electrodes, and soaking them in KCl solution can help. But they "say" that the gel in which the reference electrode is immersed lasts about 6 months to 1 year.

*Say: https://d163axztg8am2h.cloudfront.net/static/doc/1b/eb/282870e4b6bf7734d112d04a78bd.pdf

An illustration of a pair of electrodes of this type (those that are not matched) can be seen at: https://www.globalspec.com/learnmore/sensors_transducers_detectors/analytical_sensors/ph_orp_electrodes

And congratulations for the photos of the equipment, they were very good.

3 important tips that never appear on the web about using these devices:

1. In addition to the obvious problem of validity of electrodes, these equipments can give problems due to adhesion of organic material on the surface of the glass. In this case, you can leave them for 24 hours immersed in a 3% hydrogen peroxide solution (10 volumes), it may be that this will "resurrect" the equipment.

2. Another idiotic detail, but very common is that when the batteries are low they can indicate incorrect values, it should be checked before discarding the use of these equipment.

3. These devices are not waterproof, but the problem is much bigger than that - I always see that there is permeation of the solution into the circuit: that is, if you use it frequently, within 1 year (2 at most) most of the electronic components will be corroded.

Sorry for the incorrect English or the translation not being 100%.

Respectfully,

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