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INVUE CR288 CONCENTRATION MONITOR
Installation and Use Manual | Entegris, Inc.
Figure 31. First derivative tab.
A good derivative curve has a depth exceeding the
blue threshold line as shown.
MAINTENANCE
—
RE-ZERO AND RE-TITRATION
Re-zero is performed for setup, maintenance, and to
correct sensor drift.
Re-titration is an adjustment of the concentration
value and is performed as necessary.
Re-zero for Maintenance
To re-zero,
See Re-zero
for instructions. Re-zero
the sensor:
• On an as needed basis
• When changing sensors
Re-zero Due to Sensor Drift
If H
2
O is available, Re-zero the Refractive index value
to 1.33300.
NOTE: If performing a Re-zero does not correct the
problem, see
Cleaning the Sensor Window
.
Re-Titration Offset
1. Take an offline lab measurement.
2. Go to the
Sensor Calibration/Chemical Calibration
tab.
3. Enter a value to offset chemical calibration.
Figure 32. Resetting chemical concentration offset.
CLEANING AND RE-INITIALIZATION
—
PRECAUTIONS
WARNING: Before servicing any installed sensor,
you must depressurize and flush the system.
WARNING: Residual chemicals may be left in the
sensor and the system. Refer to the MDDS for
exposure precautions.
Figure 33. Disassembled sensor.
Hole plugs
Washers
Sensor
Mounting bracket
Socket head cap screws
Body
