DH Instruments COMPASS FOR MOLBOX, User Manual

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COMPASS

for molbox™ User’s Manual
Page 23
© 1998-2003 DH Instruments, Inc .
Figure 10. Example 5, DUT Definition
Select the [Setup], [DUT], [Test] tab, and select the “Calibration Gas” that you
will be using to test the DUT (see Section 8.5.6).
Select the [Setup], [DUT], [Read] tab, and select the DUT Data Output Type
(see Section 8.5.8). This is <Manual> if the DUT output cannot be read automatically.
5.1.5.2 TEST DEFINITION SETUP
There is nothing out of the ordinary about setting up a test to test a DUT that
outputs volume or actual flow units (see Section 9).
5.1.5.3 TEST HARDWARE SETUP
The installation of a DUT that measures in volume or actual flow units should be made
following the manufacturer’s recommendations for straight piping lengths, etc.
Precise volume or actual flow measurements cannot be made without the knowledge
of the actual temperature and absolute pressure of the gas at the DUT during the test.
This information can be read automatically by
COMPASS if the necessary
Hardware Definitions are included in the System Configuration (see Sections
10.3.4, 10.2). If they cannot be read automatically they must be entered manually or
set to a default value (see Section 11.6). Generally, the gas temperature and absolute
pressure measurements should be taken at the inlet side of the DUT. Some manufacturers
supply a test port for the connection of a pressure monitoring device.
The setup of manual entry of pressure and temperature is a two part process.
The
[Setup], [System], <Pressure Measurement> and <Temperature Measurement>
should both be blank when manual entry is to be used (see Section 10.2). Use the
[Tools] , [Options] , [Run Test] tab to specify whether temperature and pressure
will be entered at the “first point”, “each point” or by “use default value”.
The setup of automatic pressure and temperature measurement is a two-step process.
First the Hardware Definitions of the measuring devices need to be created using the
[Setup], [Hardware], [Temperature] and/or [Pressure] tabs (see Section 10.3.4).
Next they must be selected for use by COMPASS using the [Setup], [System],
[Temperature] and/or [Pressure] pull-down menus (see Section 10.2).