Vaisala HMT120 - Manual (Page 35)

Chapter 4 _______________________________________________________________ Service Port
VAISALA ________________________________________________________________________ 33
Calibration Commands
Serial commands that are related to calibration are described below. For
the actual calibration procedures, see section Calibration and Adjustment
on page 50.
Calibrate Humidity Measurement
Use the CRH command to perform a one-point or two-point humidity
(RH) calibration.
CRH
When performing a one-point calibration, you need to place the probe in
a single humidity reference with RH < 50%. Run the command and enter
the exact RH of the reference after the measurement has stabilized. Exit
the command by pressing the ESC key before proceeding to the second
point (see example below). To update the value, press ENTER without
inputting a value.
For two-point calibration, the first point requires a RH < 35% humidity
reference, the second point must be RH > 50%.
Example 1: One-point calibration
>crh
RH: 11.29915720 Ref1 ? 11.3
Press ENTER to continue or ESC to exit
OK
>
Example 2: Two-point calibration
>crh
RH: 11.29915720 Ref1 ? 11.3
Press ENTER to continue or ESC to exit
RH: 75.04306440 Ref2 ? 75
OK
>
Example 3: No calibration, only updating the value
>crh
RH: 20.28000200 Ref1 ?
RH: 20.14000000 Ref1 ?
Calibration terminated with ESC
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