Buffer Adjustment; Buffer Adjustment Details - Xylem MJK pHix Compact V3 NG Manual

pHix® Compact V3. NG (next generation)
EN 4.10 Version 2202

Buffer adjustment

If the transmitter is installed without the power supply turned on, please allow the
transmitter to boot-up for 1 minute before an adjustment is performed.
In order to ensure a precise and stable pH measurement, pHix® Compact must be buffer
adjusted with regular intervals. Buffer adjustment 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 reference points.
pHix® Compact is buffer adjusted using two buffers with pH values of 4.01 and 7.00
(acidic range) or pH values of 7.00 and 10.01 (alcalic range). For measurements around
pH 7 (neutral), both buffer pairs 4.01 - 7.00 and 7.00 -10.01 can be used for adjustment.
The sequence of buffer used for adjustment is not important. pHix® Compact
automatically detects which buffer is used for adjusting zero points, and which buffer is
used for adjusting the slope (the conversion between the electrodes mV and the
measured pH value).
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 4.01, 7.00 and 10.01.
First buffer adjustment with pH 7 as Second buffer adjustment with pH 4 as
reference. reference.

Buffer adjustment details

The buffer adjustment is the process that is done in order to get the main characteristics
of a pH electrode, those are slope and zero point.
The buffer adjustment is done as a 2 point adjustment. The pHix is dipped into two
different buffer solutions. This gives to points (mV, pH) that are converted then to slope
Buffer adjustment /Buffer adjustment details
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