TE-5170DV-BLX & TE-5170BLXZ 24 Operations Manual
With Qa determined, the sampler H2O reading needs to be converted to mm Hg using the following
equation:
16. Pf = 25.4 (in. H2O/13.6)
where:
17. Pf is recorded in mm Hg
18. in. H2O = sampler side pressure reading during calibration
Inserting the numbers from the worksheet:
19. Pf = 25.4(6.4/13.6)
20. Pf = 25.4(.4705882)
21. Pf = 11.95294 mm Hg
Po/Pa is calculated next. This is done using the following equation:
22. Po/Pa = 1 - Pf/Pa
23. where: Pa = ambient barometric pressure during calibration, mm Hg.
Inserting the numbers from the worksheet:
24. Po/Pa = 1 11.95294/749.3
25. Po/Pa = 1- .0159521
26. Po/Pa = .984
Use Po/Pa and the ambient temperature during the calibration (Ta) to locate the flow for the calibration
point in the Look Up table. Record this in the column titled Look Up. Calculate the percent difference
using the following equation:
27. % Difference = (Look Up flow - Qa)/Qa * 100
Inserting the numbers from the worksheet:
28. % Difference = (1.287 - 1.323)/1.323 * 100
29. % Difference = (-0.036)/1.323 * 100
30. % Difference = (-0.0272108) * 100
31. % Difference = -2.72
It is possible that your answers to the above calculations may vary. This is most likely due to different
calculators carrying numbers to different decimal points. This should not be an area of concern as
generally these variations are slight.