Tasseron Elmeco Mode D'emploi page 22

BATTERY, TYPE MN 1604
THE pH METER
The pH-meter is an instrument for measuring the acidity of a
solution. Originally, the pH—meter was a laboratory
instrument and has to be handled with due care as otherwise
the measurement may not be reliable. We have compiled this
instruction book with this in mind.
FUNCTION OF THE pH-METER
The pH-meter consists of two components, the pH probe and
the meter.
1. THE pH PROBE
The active part of the pH probe is formed by a small bulb
of very thin glass. A potential is generated across the
glass which is proportional to the acidity. Any form of
damage to, or contamination of the glass surface will alter
the measurement. The potential generated is measured
by an electrode in the bulb and via a ceramic ring around
the base of the bulb which establishes a liquid junction
with the solution to be measured. Contamination of the
ring will also alter the result. In order to ensure that the
probe functions correctly, the glass surface must be well
saturated with fluid so that a dry probe must first be
immersed in PROBECARE for 24 hours before it can be
used.
2. THE METER
The meter processes the potential transmitted by the probe
with the calibration data and the temperature correction to a
pH value which is then given on the display.
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