Vaisala HUMICAP HMP41, User Manual

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HMI41 AND PROBES
Operating Manual
M210316EN-A
10
As the D (dry) and W (wet) adjustments may affect each other, check again
the humidity reading in the LiCl salt chamber: insert the probe into the
calibration hole and wait until the reading stabilizes. If necessary, repeat the
adjustments in both the LiCl and the NaCl (K
2
SO
4
) salt chambers until the
reading is correct.
5.2 Calibration with HMI41 software commands
Calibration can also be done with the HMI41 software commands. When
calibration is done with software commands, the corrections are entered in the
indicator memory with pushbuttons. If only one probe is being used, the
HMI41 software calibration is useful. However, when several probes are in
use, calibration should be done by adjusting the probe potentiometers. Note
that when the sensor is changed, calibration must always be done by adjusting
the potentiometers and it is recommended that the HMI41 is reverted to
factory settings by selecting default calibration.
NOTE
If the factory calibration of the HMI41 is changed, the
correction data refers to the calibrated probe only.
Therefore, if you change the probe, always revert this
data to factory settings by selecting default calibration,
or perform a new calibration with the new probe.
The calibration procedure is included in the HMI41 setup mode. Enter the
setup mode by pressing the ON/OFF button. The following appears:
RH
set min max hyst hold Lo bat Hi
P Pa h g/m
T
Td
°C °F
°C °F
%
Then release the ON/OFF button and press within 1 - 2 seconds both ENTER
and MODE buttons until the following text appears on the display:
After a few seconds, the text changes automatically to show the following:
set
°C