4/9/98
A-26 Application of the Hygrometer (900-901D1)
Comparison of PPM
V
Calculations
There are three basic methods for determining the moisture
content of a gas in PPM
V
:
• the calculations described in this appendix
• calculations performed with the slide rule device that is
provided with each GE Panametrics hygrometer
• values determined from tabulated vapor pressures
For comparison purposes, examples of all three procedures are
listed in Table A-4.
Table A-4: Comparative PPM
V
Values
Dew Point
(°C)
Pressure
(psig)
Calculation Method
Slide
Rule
Appendix
A
Vapor
Pressure
-80 0 0.5 0.55 0.526
100 0.065 N.A. 0.0675
800 0.009 N.A. 0.0095
1500 0.005 N.A. 0.0051
-50 0 37 40 38.88
100 4.8 5.2 4.98
800 0.65 0.8 0.7016
1500 0.36 0.35 0.3773
+20 0 N.A. 20,000 23,072.36
100 3000 3000 2956.9
800 420 400 416.3105
1500 220 200 223.9
To Next Page
Loading...
