Using serial line, Pres and xpres, Pfix – Vaisala PTU300 User Manual
Page 112: Table 31, Conversion factors for pressure units
User's Guide _______________________________________________________________________
110 __________________________________________________________________ M210796EN-G
Using Serial Line
PRES and XPRES
Command XPRES must be used if the value is changed frequently (for
example, by an automatic system that updates the value). Its value is not
retained at reset, and when set to 0, last value set with PRES is used
instead. Use the serial line and do the following:
PRES [aaaa.a]
XPRES [aaaa.a]
where
aaaa.a = Absolute process pressure (hPa)
Example:
>pres
Pressure : 1013.00 hPa ?
>pres 1010
Pressure : 1010.00 hPa
>
Table 31
Conversion Factors for Pressure Units
From
To: hPa
mbar
1
Pa N/m2
0.01
mmHg torr
1.333224
inHg
33.86388
mmH
2
O
0.09806650
inH
2
O
2.490889
atm
1013.25
at
980.665
bar
1000
psia
1)
68.94757
1) psia = psi absolute.
Example:
29.9213 inHg = 29.9213 x 33.86388 = 1013.25 hPa
PFIX
Use the PFIX command to select either P inputted or P measured.
- When PFIX is On, fixed PRES value is used
- When PFIX is Off, measured PRES value is used