Metso 3300 Series, Manual

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MANUAL
Manual Series 3300 2. InstALLAtIon
2.7 Testing the system after installation
From factory the Metso TCU system has been set up ac-
cording to the specifications of the purchase order and
the sensor has been adjusted in the relevant liquid.
The TCU determines the concentration based on conduc-
tivity and temperature. Deviations from accurate labora-
tory analyses of the liquor may occur for various reasons,
like for instance liquor composition and installation.
After installation, it is recommended to do a test by com-
paring TCU readings with laboratory results. We recom-
mend using at least 10 readings taken over several days.
Those readings must cover the concentration range of
the TCU as far as possible.
Example:
The readings shall be plotted in a X-Y diagram to show
how well they correlate, whether the sensitivity is correct,
and whether there is any offset. When evaluating the re-
sults, the standard deviation of the laboratory tests shall
be considered. If the correlation between the laboratory
results and the TCU readings is low, the installation shall
be checked. Especially it shall be considered if air bubbles
occur and if the sensor tip is constantly surrounded by
liquid. It may also be helpful to check the working proce-
dure in the laboratory. If the correlation is satisfying but
there is a slope error and/or an offset error, the calibration
line can be changed.
See section 3.3 “Adjusting the TCU”.
G.O.S. 19661 20 - 40 % NaOH
Date Time TCU Laboratory value
021004 09:15 24.0 26.3
021004 12:00 25.1 26.9
021004 14:30 27.7 28.9
021005 09:30 34.1 34.7
021005 11:00 30.9 32.1
021005 13:30 29.0 30.0
021005 15:30 29.2 31.0
021006 09:00 24.0 29.5 disregarded
021006 11:30 32.3 33.6
021006 14:00 31.5 32.5