VOLTCRAFT PH-212 Notice D'emploi page 34

HOLD function
The measured values currently displayed are retained on the dis-
play. Press the „HOLD" button (3) to activate this function. Press
again to switch back to the normal measuring mode.
Maintenance and Cleaning
Contaminations and deposits on the electrode affect the result of
measurement. Therefore it is important to keep the electrode always
clean. Use only distilled or de-ionised water for cleaning (rinsing) the
pH-electrode and paper napkins for dabbing. Do not use detergents
that contain carbon, petrol, alcohol or similar substances for clean-
ing purposes. This will corrode the surface. Moreover the vapours
are detrimental to health and explosive. Sharp-edged tools, screw-
driver or metal brushes are a taboo for cleaning.
Always store the pH electrode in the provided storage solution.
While doing so first put on the end cap on the electrode. Now put on
the o-ring on the electrode and screw the end cap to the tin.
Replacing the battery
If the battery symbol „ " is displayed on the display, the batteries
– +
must be replaced as soon as possible to prevent erroneous mea-
surements.
To replace the batteries, proceed as follows:
- Switch off the device.
- Loosen the two battery compartment screws on the back of the
device, and slide the lid of the battery compartment (5) out of the
housing.
- Replace the run-down battery with a new one of the same type
(e.g. 1604A).
- Close the measuring device again carefully in reverse sequence.
Do not leave run-down batteries in the measuring device.
Even leak-proof batteries can corrode and thus release
chemicals which can be detrimental to your health or
damage the appliance.
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Controls and indicators
1. LC display 6. Calibration trimmer pH7
2. ON/OFF button 7
3. HOLD button 8. BNC connecting plug
4. BNC connection- 9. electrode grip
electrode socket 10. electrode storage solution
5. battery compartment
Commissioning
Inserting the batteries
Before the commissioning of this meter, you must first install a new
9 V battery pack. Insertion of battery is described in the „Mainte-
nance and Cleaning" section.
Calibration
Calibration is necessary in order to optimally adapt the electrode to
the pH meter. An optimal pH electrode outputs a voltage of 0 mV at
a temperature of 25°C and a pH value of 7.00. However, since each
electrode is different and deviates from the optimum depending
upon the temperature and the wear and tear, it must always be
adapted to the pH measuring device for achieving the highest pos-
sible accuracy.
Calibration trimmer pH4
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