ELMETRON CP-511 - Preparation of the Ph Electrode

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7. Preparation of the pH electrode
The electrode should be prepared to work according to the manufacturer’s
instructions. If the instructions weren’t given please follow the steps:
- new electrode should be put into saturated KCl solution for about 5 hours:
- before starting measurements, protecting rings (if used in this kind of
electrode) should be removed. The ring placed on the junction – the lower
part of the electrode - should be removed upwards along the electrode’s
body and the upper, which protects the KCl refilling hole, downwards
along the body. Removing the lower ring is essential, in other case the
electrode won’t measure. The upper ring should be removed during
measurements of high-temperature solutions or to protect the junction
during measurements in solutions with deposits or oils. Sometimes
instead of ring a cork is used;
- during measurements in laboratory it is advisable to use an electrode
holder;
- after every measurement the electrode should be washed in distilled
water;
- excess of liquid on the electrode should be removed by gentle touching
the glass with a tissue paper;
- after work the electrode should be stored in the KCl solution. Protecting
rings should be put on the junction and the upper hole;
- in case of long breaks between measurements the electrode should be
stored, after drying, in the packaging;
- after taking the electrode out of the package the deposit, which is likely to
appear, should be removed with use of water;
- before use, the electrode should be placed in saturated KCl solution for
about 1 hour;
- if the construction of the electrode enables refilling the electrolyte, it
should be controlled and refilled periodically by the upper hole in the
electrode’s body (usually as the electrolyte a KCl solution is used).
- If the electrode is equipped with a small container (bottle) put on its end,
the bottle should be taken off before measurements by unscrewing the nut
gently and taking the bottle down the electrode’s body. After the
measurements the bottle should be put on again. Such electrodes are not
equipped with the protective ring on the junction and do not require
activating the membrane.
Note: storing the electrode in distilled water shortens its life span and
may heighten the measurement error.