Vaisala Drycap DMT142, Руководство пользователя

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User's Guide _______________________________________________________________________
24 ___________________________________________________________________ M210397EN-D
Pressure Compensation
In pressurized environments, in order to optimize the accuracy of the
DMT142, the actual process pressure can be set to the DMT142 if the
pressure setting is not configured when ordering the product. In a
worst case scenario, an incorrect pressure setting may result in an
additional uncertainty of 1.5 °C in the dewpoint measurement. The
worst case is considered to be the dewpoint temperature T
d
at its
lowest limit with the widest possible pressure setting difference.
Syntax: PRES pppp.pp<cr>
where
pppp.pp = absolute pressure (bar
a
) in the measuring point
Example:
>pres 1.01325
Pressure : 1.013
in use : 1.013
>
The pressure conversion coefficients from other pressure units to bars
is given in the table below.
Table 6 Pressure Conversion Coefficients
From To bar
a
PaN/m² 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
NOTE Conversions from mmHg and inHg are defined at 0 °C and from
mmH
2
O and inH
2
O at 4 °C.