ProMinent DULCOTEST PAA 1-mA-200 ppm, Operating Instructions Manual, Page: 38 / 100

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Pr o Minent ®
8.2 Calibration
CAUTION
• You must perform a slope test after changing a diaphragm
cap or electrolyte.
• You should perform a slope test at regular intervals to
ensure flawless operation of the measuring cell.
• You should observe the relevant national regulations in
force for calibration intervals!
Conditions Operation of the measuring cell is stable (no possible drift or fluctua-
ting measured values during a minimum period of 5 minutes). This is
generally guaranteed when the following conditions are fulfilled:
• the relevant running-in time has been allowed (see section 8.1
running-in time).
• permitted flow is present in the in-line probe housing (see section
14 technical data).
• Temperature compensation achieved between measuring cell and
sample water (wait approx. 15 minutes).
Zero point calibration Zero point calibration is not required.
Slope test
IMPORTANT
• After an initial commissioning, check calibration after 24
hours.
• Repeat calibration if the PES concentration varies by more
than 15 % from the reference value.
There are two ways of performing a slope test for the peracetic acid
(PES) measuring cell:
• via two-stage titration (precise method: see appendix for titration
index)
• via a PES standard solution (with a known PES concentration)
Commissioning
BA_DT_097_10_08_4spr.p65 09.10.2008, 13:19 Uhr 38