DH Instruments COMPASS FOR MOLBOX, User Manual

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COMPASS

for molbox™ User’s Manual
© 1998-2003 DH Instruments, Inc .
Page 18
5.1.2 EXAMPLE #2
Assuming the molbox1 from Example 1 is set up and it has the MFC control option,
“How do I calibrate a DUT that outputs 0 to 5 V corresponding to 0 to 1 slm?”
This example demonstrates the setup requirements of a common analog output DUT. The only
setup required to use the molbox MFC control option is to make sure the molbox is set up
with the proper remote interface in a Reference Hardware Definition and select the molbox in
the System Configuration (see Section 10).
5.1.2.1 SETUP <VOLTAGE/CURRENT> OUTPUT TYPE
Use the [Setup] , [DUT] menu choice to open the DUT Definition Editor (see Section 8).
Create a new DUT Definition and set up the basic header information corresponding
to the DUT. In the
[Range] tab (see Section 8.5.4), select the flow range units
from the flow units list and enter the flow min and max values; 0 and 1 respectively.
Check the
<Controller> checkbox on the <Set Range> panel. Now type or
select “V” as the output and set units. Enter 0 and 5 as the min and max output
and set point values. DUT’s that use voltage or current signals to indicate flow
should use the
<Voltage/Current> < Output Type> . This tells COMPASS to use
the instrument currently selected as the <DUT Output DMM> in the System
Configuration to measure the DUT flow. Select <Voltage/Current> as the DUT
< Set Mode> . This tells COMPASS to use the <Set Point Power Supply>
selected in the Hardware Definition to control the DUT flow. Use the <Save>
toolbar icon to save the DUT.
5.1.2.2 REFERENCE SETUP
Since we have assumed the reference molbox in Example #1 is already properly
set up, we only need to make the necessary Hardware Definition selections to
use the MFC control option. Use the
[Setup] , [System] menu option to display
the <System Config> form (see Section 10.2). First select the molbox as the
<Reference> . This automatically adds a <Reference molbox> option to the
<Set Point Power Supply> , <Set Point DMM> and <DUT Output DMM> lists.
Select <Reference molbox> in all lists. If it were desired to set with the molbox but
measure with a DMM, the DMM should be selected in the <DUT Output DMM> list.
5.1.2.3 RUN THE TEST
Use [Run] , [Run Test] to start a test sequence. Select the DUT just created and
the desired Test Definition when prompted. There is no interface selection
required when setting up the DUT interface during the test initialization.