Vaisala HMP155 - Manual (Page 38)

USER'S GUIDE____________________________________________________________________
36 _______________________________________________________________ M210912EN-C
Pressure Compensation Commands
PRES and XPRES
Use the PRES serial line command to set ambient pressure value for
fixed pressure compensation. If the value is changed frequently, use the
XPRES
serial line command. Its value is cleared to 0.0 at reset; if it is set
to other than 0, it overrides the setting given with the PRES command.
NOTE In normal pressure conditions, PRES command is not needed. But if
mixing ratio is used in high altitudes, the pressure changes will increase
the mixing ratio.
Use the serial line and do the following:
PRES [a.aaaa]
where
a.aaaa = Ambient pressure value (bar)
Example:
>pres
Pressure : 1.013 bar ?
>
XPRES [a.aaaa]
where
a.aaaa = Ambient pressure value (bar)
Example:
>xpres
Pressure: 0.000 bar ?
>