INVUE CR288 CONCENTRATION MONITOR
27
Installation and Use Manual | Entegris, Inc.
APPENDIX A: ADVANCED FEATURES
—
CREATE A NEW CHEMICAL CALIBRATION TABLE
Create a different Chemical Calibration Table for
each chemical the sensor monitors.
Select the
Sensor Calibration / Chemical
Calibration
tab.
1. Change the chemical name and press
Delete All
Points
. This clears all data from the chemical
concentration table.
2. The next steps depend on the available information,
such as data from an offline analysis. See
Calibrate
Sensor to a Chemical
.
3. When the desired number of points are recorded,
press
Save Present Chemical.
The software writes a file with a *.chem extension
on the hard drive. This file can then be used to
import the chemical calibration table to other
sensors.
4. Press
Save Memory
to update the sensor memory.
TEMPERATURE COMPENSATION WIZARD
The Temperature Compensation Wizard (TCC Wizard)
allows users to employ an automatic temperature
compensation feature to desensitize the product’s
refractive index response to temperature change.
This feature provides an adequate baseline for most
processes. For finer control of temperature compen-
sation, you may use a manual temperature compen-
sation procedure. Manually removing stray points
from the data log in Microsoft Excel
®
can also
improve the performance of the TCC Wizard.
The need for temperature compensation depends
on the consistency of the process. If the process is
known to vary, you may need to perform temperature
compensation several times during setup.
1. Select the
Data Graph
tab.
2. Let the sensor run for the period of time and the
range of temperatures representative of a typical
process cycle. Keep the chemical concentration
constant.
3. Press
Adjust Temperature Compensation
.
The TCC wizard window opens.
4. Determine if the response of the sensor is under-
or over-compensating for temperature. See
Figure 36. TCC wizard screen 1
.
5. Using the graph on the left, zoom in on the data set
to use to calculate the temperature compensation
value. Take data near the target temperature and
concentration of the application.
Figure 36. TCC wizard screen 1.
6. Press
Regression Fit
under FTCC1. The software
calculates the fluid temperature compensation
value (FTCC1) and the Temperature Compensated
IoR. The right-hand graph shows the effect of the
temperature compensation on the data graph
FTCC1.
Note: Used in every case, this linear model for tempera-
ture compensation is appropriate as the sole tempera-
ture compensation for most systems.