Vaisala HMP240 - Manual (Page 76)

HMP240
Appendix 1: Serial commands
M210300en
74
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 <cr>
RH : 1.90
Ref1 ? 11.3 <cr>
FCRH 2 <cr> ...
RH : 76.30
Ref2 ? 74.9 <cr>
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<cr>
at Ref1 and Ref2:
>FCRH <cr>
RH : 12.00
Ref1 ? c <cr>
RH : 11.70 Ref1 ? c <cr>
RH : 11.50 Ref1 ? 11.3 <cr>
Press any key when ready ...
RH : 76.00
Ref2 ? 75.5 <cr>
CT Temperature calibration of the humidity sensor head
Disconnect the security lock jumper!
CT <cr>
With this command the humidity sensor head can be calibrated against an
accurate reference, such as a Pt 100 simulator. A two-point calibration is per-
formed as follows:
>CT <cr>
T : 0.80
Ref1 ? 0.0 <cr>
Press any key when ready ...
T : 56.20
Ref2 ? 55.0 <cr>
In one-point offset correction, the Ref2 prompt is acknowledged with <cr>:
>CT <cr>
T : 0.80
Ref1 ? 0.0 <cr>
Press any key when ready ...
T : 75.50
Ref2 ? <cr>
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<cr> at Ref1 and Ref2:
>CT <cr>
T : 0.80
Ref1 ? c <cr>
T : 0.40 Ref1 ? 0.00 <cr>
Press any key when ready ...
T : 56.20
Ref2 ? 55.0 <cr>