Nvis901
Direction for Use pH Electrode
1.
Remove the bottle/protective cap at the bottom of the electrode.
2.
Shake the electrode gently to ensure that the internal buffer solution covers the whole pH
bulb and no air bubbles are entrapped.
3.
pH combinational electrodes should be filled with the appropriate electrolyte to a height of
about 1 cm below the filling port.
4.
Wash off any salt film present on the exterior of pH combination electrode, using distilled
water.
5.
To ensure pressure equalization, the stopper of the filling port should be removed or
perforated with a pin.
6.
Soak the electrode in 7 pH buffer or saturated KCL for some hours (preferably overnight)
below use.
7.
Electrode which have developed problem of slow response due to drying out of the
membrane or use under extreme conditions, may be re-activated by soaking in 0.1 N
hydrochloric acid for 8 to 10 hours.
Electrodes, which fail to respond to the above treatment, can be further activated by dipping
them to 2% hydrofluoric acid for 5-10 seconds and immediately washing with distilled water.
This drastic treatment should however be applied only as last resort as it reduces the life of
the electrode.
8.
After conditioning the electrodes as in (7) above, if it is not to be used it should be kept in
7pH buffer or saturated KCL. To prevent the entry of measuring media through the
diaphragm of the reference junction of pH combination electrode, the stopper of the filling
opening/ port should be removed or perforated with a pin.
Important for pH combinational Electrodes:
1.
Always keep the electrode dipped in saturated KCL solution, when not in use.
2.
Since the shelf life of the buffer is very short, for correct results it is strongly
recommended to use freshly prepared buffers for calibration
3. In any case, kindly do not take any step not mentioned in our “Direction for use”
(Moreover, do not remove the cap on top of the electrode which will make the electrode
ineffective).
Nvis Technologies Pvt. Ltd.
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