DH Instruments COMPASS FOR MOLBOX, Руководство пользователя

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COMPASS

for molbox™ User’s Manual
Page 101
© 1998-2003 DH Instruments, Inc .
Table 34. <System Configuration> Screen Fields
FEATURE DESCRIPTION
Flow
Reference
(drop down list
selection)
This is the source of reference flow values in the COMPASS run modes. The drop down list choices
are created using the Hardware Definition [Reference] tab (see Section 10.3.3). This is a
required selection as all run modes include measurement of reference flow. A molbox is the
only reference flow device for which remote communications are supported. All other
reference devices require manual entry in run modes. When a molbox reference is selected,
molbox specific features are selectable in other System Configuration fields.
DUT Output
DMM
(drop down list
selection)
This is the device used to read the output of DUTs whose <Output Type> is
<Voltage/Current> in the DUT Definition [Read] tab (see Section 8.5.8). The drop down list
choices are created using the Hardware Definition [DMM] tab (see Section 10.3.4). If a
molbox is selected as the <Flow Reference> , <Reference molbox> is a choice in this list. A
selection in this category is required only to run <Voltage/Current> output type DUTs.
Set point power
supply
(drop down list
selection)
This is the device used to send analog set point values to DUTs that are checked as flow
controllers in the DUT Definition
[Range] tab and whose <Setpoint Type> is
<Voltage/Current> in the DUT Definition [Set] tab (see Sections 8.5.4, 8.5.9). The drop
down list choices are created using the Hardware Definition [Power Supply] tab (see Section
10.3.5). If a molbox is selected as the <Flow Reference> , <Reference molbox> is a choice
in this list. A selection in this category is required only to run DUT’s that are flow controllers
and whose set point type is
<Voltage/Current> .
Set point DMM
(drop down list
selection)
This is the device used to measure the analog set point value to DUTs that are checked as
flow controllers in the DUT Definition
[Range] tab and whose <Setpoint Type> is
<Voltage/Current> in the DUT Definition [Set] tab (see Sections 8.5.4, 8.5.9). The drop
down list choices are created using the Hardware Definition [DMM] tab (see Section 10.3.4).
This is the same list as the <DUT Output DMM> in this screen. A selection in this category is
required only when the DUT being run is a flow controller, its set point type is
<Voltage/Current> and the test being run specifies <Set Point> data acquisition (see Section
9.5.9).
Frequency
Measurement
(drop down list
selection)
This is the device used to read the output of DUTs whose <Output Type> is <Frequency> in
the DUT Definition [Range] tab (see Section 8.5.4). The drop down list choices are created
using the Hardware Definition [Frequency] tab (see Section 10.3.4). A selection in this
category is required only to run <Voltage/Current> output type DUTs.
Pressure
Measurement
(drop down list
selection)
This is the device used to automatically read the gas pressure at the DUT for DUTs that
specify a
<Gas Density Correction Type> in the DUT Definition [Correction] tab (see
Section 8.5.3) or when a Test definition has the DUT pressure option checked on the [Data]
tab(see Section 9.5.9) The drop down list choices are created using the [Pressure] tab in the
Hardware Definition (see Section 10.3.4). If a molbox is selected as the <Flow Reference> ,
<molbloc upstream pressure> and <molbloc downstream pressure> are choices on this
list. There are no circumstances in which a selection is required. If a selection is present,
COMPASS will attempt to use the specified device to measure the absolute pressure of the gas
at the DUT when applicable. If no automated pressure measurement device is available, select
<Manual> .
molbox upstream or downstream pressure can only approximate the pressure of
the gas at the DUT since, due to the flow in the system, the pressure at the
molbloc and at the DUT cannot be identical. Keep this in mind when estimating
the uncertainty on the DUT pressure.