Vaisala HMP240 - Manual (Page 89)

HMP240
M210300en Appendix 1: Serial commands
87
The time can be set in seconds within the range of 0 - 1024 (0 = no averaging
time).
For example:
>FILT
Filter (S):
0 ? 1024
>
>FILT 100
Filter (S):
100
>
PRES Setting the pressure for mixing ratio and wet bulb
temperature calculations
PRES pppp.pp
pppp.pp = pressure (hPa)
The atmospheric pressure has an effect on mixing ratio and wet bulb
temperature. Therefore, accurate calculations can be achieved only when the
ambient pressure is taken into consideration. The pressure is used for pressure
compensation of the HUMICAP

sensor in order to ensure the best possible
measurement accuracy.
When the command is given, the transmitter first gives the currently used
pressure; after this a new value can be entered or the old one acknowledged.
>PRES
Pressure : 1013.25 ? 1000.00
When the currently used pressure is known, a new pressure can also be entered
directly:
>PRES 1010
Pressure : 1010
NOTE
If the pressure setting is frequently adjusted, e.g. by
using an external barometer as a pressure input source,
the command XPRES is recommended.