DH Instruments COMPASS FOR MOLBOX, Руководство пользователя

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COMPASS
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for molbox™ User’s Manual
Page 21
© 1998-2003 DH Instruments, Inc .
Select the [Setup], [DUT], [Test] tab, and select the “Calibration Gas” that you
will be using to calibrate the rotameter (see Section 8.5.6).
Select the [Setup], [DUT, [Read] tab, and select “Manual” for the DUT Output
Type (see Section 8.5.8).
5.1.4.2 TEST DEFINITION SETUP
There is nothing out of the ordinary about setting up a Test Definition for a
rotameter (see Section 9), except that
<Jog Before Dwell> should be checked
on the [Control] if you are using the <Other Controller > method of flow controls
and you want to adjust flow to the rotameter ball or cardinal points before taking
data (see Section 9.5.6).
5.1.4.3 TEST HARDWARE SETUP
The installation of the rotameter into the test plumbing should be made following
the manufacturer’s recommendations. In general, if the flow controlling device is upstream
of the rotameter, the gas pressure and temperature measurements should be taken
on the outlet side of the rotameter. If the flow control valve is on the outlet of the rotameter,
the pressure and temperature measurements should be taken at the inlet of the rotameter.
Precise calculation of the flow to take into account that the rotameter is affected
by gas density cannot be made without knowledge of actual gas temperature and
absolute pressure at the rotameter during the test. This information must be
entered manually when a test is run if it can’t be obtained automatically.
The setup of manual entry of pressure and temperature is a two-part process. The [Setup],
[System], <Pressure Measurement>, and <Temperature Measurement> selections
should both read <Manual> when not using automated reading devices (see Section 10.2).
Then, use the [Tools] , [COMPASS Options] , [Run Test] Tab to specify either
“first point”, “each point” or “use default value” for the manual entry method of the
gas pressure and temperature (see Section 11.6).
The setup of automatic pressure and temperature measurement is a two-step process.
First the Hardware Definitions for the devices used to measure pressure and
temperature must be created using the
[Setup], [Hardware], [Temperature]
and/or [Pressure] tab (see Section 10.3.4). Next the devices must be selected
in the System Configuration using [Setup], [System], [Temperature] and [Pressure]
pull-down menus (see Section 10.2).
Figure 9. Example 4, System Configuration