Vaisala HMP228 User Manual
Page 56

HMP228 Transmitters
Appendix 1: Serial commands
M210282en-A
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The command can also be divided into two commands, so the computer can be
used for other purposes while waiting for the sensor to stabilize to the higher
humidity.
>FCRH 1
RH : 1.90
Ref1 ?
11.3
FCRH 2
RH : 76.30
Ref2 ?
74.9
If the stabilization of the sensor to the humidity in the calibrator needs to be
monitored, the measurement output can be repeated by giving command c
at Ref1 and Ref2:
>FCRH
RH : 12.00
Ref1 ? c
RH : 11.70
Ref1 ? c
RH : 11.50
Ref1 ? 11.3
Press any key when ready ...
RH : 76.00
Ref2 ? 75.5
CT
Temperature calibration
Disconnect the security lock jumper!
CT
Using this command the transmitters can be calibrated against an accurate ref-
erence, such as a Pt 100 simulator. A two-point calibration is performed as
follows:
>CT
T : 0.80
Ref1 ?
0.0
Press any key when ready ...
T : 56.20
Ref2 ?
55.0
In one-point offset correction, the Ref2 prompt is acknowledged with
>CT
T : 0.80
Ref1 ?
0.0
Press any key when ready ...
T : 75.50
Ref2 ?
If the stabilization of the sensor to the temperature of the calibrator or the ref-
erence needs to be monitored, the measurement output can be repeated by giv-
ing command c
>CT
T : 0.80
Ref1 ?
c
T : 0.40
Ref1 ?
0.00
Press any key when ready ...
T : 56.20
Ref2 ?
55.0