Vaisala Drycap DMT152, User Manual

Page: 47 / 72

The pressure conversion coefficients from other pressure units to bars are given in Table 25
(page 45) .
Table 25 Pressure Conversion Coefficients
From To bar
a
PaN/m
²
0.00001
mmHg torr 0.001333224
inHg 0.03386388
mmH
2
O 0.00009806650
inH
2
O 0.002490889
atm 1.01325
at 0.980665
psi
a
0.06894757
Example:
29.9213 inHg = 29.9213 × 0.03386388 = 1.01325 bar
a
Conversions from mmHg and inHg are defined at 0 °C and from mmH
2
O and
inH
2
O at 4 °C.
You can also set the pressure compensation value when you connect DMT152 to
the MI70 indicator. When using MI70, the pressure unit is bar
a
.
5.5.3 Set Molar Mass for ppm
w
Calculation
Use the MOL command to view and set the molar mass of the gas in the measurement
environment. The molar mass parameter is used in calculating H
2
O ppm
w
. Some typical molar
masses are:
Air 28.96 g/mol
N
2
28.0134 g/mol
O
2
32.00 g/mol
SF
6
146.06 g/mol
Chapter 5 – Serial Line Operation
45