DH Instruments COMPASS FOR MOLBOX, User Manual

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COMPASS

for molbox™ User’s Manual
© 1998-2003 DH Instruments, Inc .
Page 28
“Ref Q” in the data grid is the reference flow expressed in the DUT flow units
without any Gas Density Correction applied. This is the true value of the flow
that is currently going through the DUT. This value is interesting because it
shows the magnitude of the correction being applied due to the difference
between current gas pressure and temperature conditions and the DUT’s normal
operating conditions. ”Req Q” should NOT be used as the reference flow value
in this example.
When no Gas Density Correction is being applied, the “Ref Q DUT Cond” value
is equal to the “Ref Q” value. Therefore, “Ref Q DUT Cond” can be used as the
reference flow for all tests in both the Data Grid and Report Editor.
5.1.8.5 RUN THE TEST
Generally, in this type of calibration, the flow is adjusted so that the DUT output is
on a cardinal point.
If DUT output, pressure and temperature entries are set up for manual entry,
COMPASS will prompt you to enter them at the appropriate times during the test.
Be sure to enter these values in the units requested. These units can be changed
using
[Tools], [Options], [Run Test] tab .