3 calibration by comparison/grab sample, Calibration – Hach-Lange SI792(x) E HACH GLI 3700 series SI792(x) T 7MA2200 and 8398 series User Manual User Manual
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Calibration
74
8.1.3 Calibration by comparison/grab sample
The sensor can be calibrated by measuring the process water with a
portable instrument or taking a grab sample and measuring its value in
the lab (one-point calibration). The sensor does not need to be removed
from the process during calibration. The sample temperature should
correspond to the measured process temperature for accurate results.
Note: The calibration by comparison option is not available when the
selected range and units is set to 000.0%.
1. Press
CAL
, enter passcode: 1105,
ENTER
. The display will briefly
show CAL PRD and then StorE.
2. Measure the process water with a portable instrument or collect a
grab sample for measurement in the lab. Press
ENTER
to proceed.
The cal mode indicator will flash to indicate that calibration has not
been completed. The transmitter will continue to measure and
display the current sample values.
3. Measure the grab sample with a laboratory or portable meter.
4. Press
CAL
, enter passcode: 1105,
ENTER
to access the product
calibration once more. The display will briefly show CAL PRD and
then CALC.
5. Edit the displayed value to match the value measured by the
laboratory or portable meter and press
ENTER
. The display will
show the new cell constant.
6. Press
ENTER
to end the calibration. The display will show the
measured value alternating with Hold.
Press
ENTER
to return to the measuring mode. The outputs will remain
in the hold mode for approximately 20 seconds.
Note: For comparison calibration via Foundation Fieldbus, see