Brouwland pH110 Manual Download

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A pH meter is a precision measuring device that requires proper use and good maintenance.

The principle of a pH meter:

There is always a reference electrode and an indicator electrode. The reference electrode has a set value and thus
provides a fixed reference against the indicator electrode. The indicator electrode can be easily distinguished from
the reference electrode. The indicator electrode very often takes the form of a glass bulb (globe). In certain other
models this is a window. This little glass bulb is very vulnerable and will have to be protected against all kinds of
influences. Only fluids may come into contact with it. So do not use fingers, tissues, paper, brushes or the like.
The indicator electrode is positioned in an electrolytic environment.

The disadvantage of the pH meter is that unfortunately the electrodes are not permanent. Many electrodes are
spent after only one year. The useful life is determined not only by the number of times of use but also by the way
in which they are used and maintained.

The better you protect your meter the longer its useful life.
Some tips:

- Always rinse the electrode in demineralized water (before and after use). Make certain that no residues adhere
to the electrode.
- Always keep the electrode in some preserving fluid (in the phial, on the sponge)
- Never keep the electrode in demineralized water.
- If crystals form (after long storage without use), rinse with demineralized water and leave to steep one day in
preserving fluid.
- If the measured value appears slowly this indicates reduced electrode activity.
- If you have a refillable electrode that you wish to refill, first bleed the electrode. The electrolyte is no longer fit
for purpose and will have to be replaced. So always replace all of the electrolyte.
After refilling allow the meter to stabilize for a few hours and then recalibrate.
- A temperature above 50°C is not good for the electrode and reduces useful life.
- The reason for the repeated recalibrations of a pH meter has to do with the constantly reduced
activity of the electrode.
- Always start calibration with a pH 7 buffer fluid. Follow with pH 4. When changing the buffer fluid, always rinse
thoroughly with demineralized water.
o Calibrate weekly after daily use
o Calibrate monthly after weekly use
o Calibrate each time after one-off use
- Keep the buffer fluids preferably in a refrigerator and allow them to reach room temperature before use.
- Do not reuse used buffer fluid; this will be contaminated by, e.g., exposure to air.
- Never place the electrode directly in the flask with the buffer fluid; better to decant a little into a small container.
- Change electrodes:
o if calibration is no longer possible
o if refilling (if applicable) is no longer possible
o if cleaning does not help
o if the electrode is damaged