Xylem MJK pHix Compact, Руководство пользователя

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pHix® Compact
EN 4.10 Version 2007
Buffer adjustment / Buffer adjustment in general
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Buffer adjustment
Buffer adjustment in general
In order to ensure a precise and stable pH measurement, pHix® Compact must
be buffer adjusted with regular intervals. Buffer adjustment is a calibration,
which is carried out in practice by dipping pHix® Compact in solutions (buffers)
with known pH values. The calibration is made by using these known pH values
as a reference point.
pHix® Compact is buffer adjusted using two buffers with pH values of 4 and 7
(acidic range) or pH values of 7 and 10 (alcalic range). For measurements
around pH 7 (neutral), both buffers can be used.
The sequence of different pH buffer solutions is not important. pHix® Compact
automatically detects which buffer is used for adjusting the point of origin, and
which buffer is used for adjusting the slope (sensitivity).
The first reference point sets the correct zero point for the measurement curve,
and the second reference point sets the correct slope for the measurement
curve.
pHix® Compact is, as standard, delivered to use buffer values at 4, 7 and 10,
but other values can be chosen via HART® communication.
First buffer adjustment with pH 7 as
reference.
Second buffer adjustment with pH 4
as reference.