Hach si792 D series, User Manual

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Section 8 Calibration
8.1 Calibration
The transmitter is adjusted to the sensor through the calibration. The
available calibration methods are shown in
Table 21
. Calibrate the
sensor in air when the sensor can be removed from the process. The
sensor will stabilize more quickly in air.
When the sensor cannot be removed from the process (e.g. sterile
processes), the process medium must be aerated during calibration
(e.g. after sterilization).
During calibration the transmitter remains in the Hold mode for safety
reasons. The loop current is frozen at the value specified in the
o1.HoLD menu option. The Sensoface icon is inactive. The calibration
mode indicator is displayed (
Figure 12 on page 33
).
To exit the calibration mode at any time, press
CAL
and then
ENTER
.
The output current will be held for 20 seconds and the measured value
will be displayed.
Note: Calibrations must be performed by trained personnel. Incorrectly
set parameters may result in errors in sample measurements.
Table 21 Calibration methods and passcodes
Method Passcode
Zero calibration 1001
Temperature probe adjustment 1015
Zero/slope display 0000
Calibration in air or water 1100
Calibration by product comparison 1105