Calibrate Humidity Measurement - HMM100

HMM100 User Guide

Document code
M211024EN
Revision
E
Language
English (United States)
Product
HMM100
Document type
User guide

CRH<cr>

Use the CRH command to perform a one-point or two-point correction to the humidity measurement of the module. This command changes the offset and gain of the measured capacitance, and therefore affects humidity measurement over the entire temperature range. Take care when making this adjustment, and ensure you make a note of the existing values before adjusting them.

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 the first example below).

For two-point calibration, the first point requires a RH < 50 % humidity reference, the second point must be RH > 50 %. There must also be at least 30 percentage points of difference between the references.

Remember to save the changes!
Example (one-point calibration):
>crh
RH:      11.29915720 Ref1 ? 11.3
Press any key when ready
>save
Saving settings...done
>
Example (two-point calibration):
>crh
RH:      11.29915720 Ref1 ? 11.3
Press any key when ready
RH:      75.04306440 Ref2 ? 75
OK
>save
Saving settings...done
>