Hach-Lange SI792 P, SI792x P, SI792x P-FF, SI792x P-PA User Manual - Manual (Page 71)

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Section 8 Calibration
8.1 Calibration
The transmitter is adjusted to the probe through the calibration. The
available calibration methods are shown in
Table 18 .
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 11 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.
8.1.1 pH calibration
The pH probe can be calibrated by automatic buffer recognition, by
manual buffer entry or by comparison to an alternate measurement
method. A one-point or two-point calibration is accepted when buffer
solutions are used. If calibration data is available for the probe, the
slope and offset can be entered.
ISFET probes or probes with an offset or isopotential other than pH 7
require an offset adjustment before calibration.
Table 18 Calibration methods and passcodes
Method Passcode
pH or ORP calibration by method specified in
configuration menu (
Table 9 on page 40 )
1100
Adjustment of temperature probe 1015
Cal info 0000
pH or ORP calibration by comparison
1105 (not available with
si792x P-PA)
Zero pH adjustment (for ISFET type probes only)
1001 (not available with
si792x P-PA)