DH Instruments COMPASS FOR MOLBOX, Руководство пользователя

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COMPASS

for molbox™ User’s Manual
Page 79
© 1998-2003 DH Instruments, Inc .
Table 23. DUT Definition Editor, [Set] Tab Fields
FEATURE DESCRIPTION
Set Point Type
(conditional drop
down list
selection)
Specifies the manner in which set point commands are given for DUTs that can control flow. If the
DUT is NOT set up as a controller in the DUT Definition
[Range] tab (see Section 8.5.4), this field
is disabled and the flow control method will be determined by the Test Definition or a [Run DUT]
initialization selection (see Sections 9.5.6, 11.6). For DUTs that do control own flow, the available
selections are:
•
Voltage/Current: The DUT flow setpoint command is an analog electrical value supplied
by an analog power supply. To run tests, the analog power supply that COMPASS is to use
must be specified as the <Set Point Power Supply> in the System Configuration (see Section 10.2).
The analog option of a reference molbox1 is an option in this list. The set point unit must be:
V, mV, A or mA when this selection is used.
COMPASS automatically makes the necessary
conversions from the original target flow units, to the set point units to the power supply units.
•
RS-232: The DUT flow setpoint command is an ASCII string it receives over its RS-
232 interface. If <RS323> is the <Set Point Type> selection, <RS232 Settings> must
be specified correctly. The [Set] tab <Initialization Commands> will be issued during
run mode initialization, then the <Set Commands> will be issued as needed to set the
flow. Responses to set commands are not used or handled by COMPASS. By
default, the RS-232 settings and the initialization commands are the same as those set
up in the DUT Definition
[Read] tab <Output Type> when the output type is also RS-
232 (see Section 8.5.8). See Section 13.3 concerning RS-232 communications.
•
IEEE-488: The DUT flow setpoint command is an ASCII string it receives over its
IEEE-488 interface. If <IEEE-488> is the <Set Point Type> selection, the <IEEE-488
address> of the DUT must be specified correctly. When tests are run, a valid IEEE-
488 card must be specified in the System Configuration (see Section 10.2). The [Set]
tab <Initialization Commands> will be issued during run mode initialization, then the
<Set Commands> will be issued as needed to set the flow. Responses to set
commands are not used or handled by COMPASS. By default, the < IEEE-488
Address> and the <Initialization Commands> are the same as those set up in the
DUT Definition [Read] tab <Output Type> when the output type is also IEEE-488 (see
Section 8.5.8). See Section 13.4 concerning IEEE-488 communications.
See Section 13 for information on COMPASS remote communications.
Initialization
Commands
(conditional drop
down list/action
button)
These are the commands needed to initialize a DUT whose <Set Point Type> is RS-232 or
IEEE-488.
Click the <Edit> button to display the <Remote Command Editor> form (see Section 13.2).
Enter the desired commands then close the form. These commands will be issued during the
initialization process of
[Run DUT] and [Run Test] run modes when the DUT <Set Point Type>
is RS-232 or IEEE-488. If the DUT does not require a specific initialization this field is not used.
Refer to the DUT’s remote interface manual to determine whether initialization commands are
necessary. Possible initialization commands include: setting unit of measure, gas or range.
If initialization commands are needed, enter them in the remote command Editor. All commands
entered will appear in appropriate list box. Consider that initialization commands may also be included
on the DUT Definition
[Read] tab if the DUT uses the same interface for reading and setting.
See Section 13 for information on COMPASS remote communications.
Set Commands
(conditional drop
down list/action
button)
These are the commands needed to set a DUT whose <Set Point Type> is RS-232 or IEEE-488.
Click the <Edit> button to display the <Remote Command Editor> form (see Section 13.2).
Enter the desired set commands then close the form. Up to 10 commands can be included.
All commands entered will appear in the appropriate list box. Refer to the DUT manual for details
on how the DUT interface functions.
Set commands typically require the <Set Unit Variable> to specify where the numerical target
flow information should be located in the command string. Enter the command string then drag
and drop or type the <Set Unit Variable> text into the appropriate location in the command
string. COMPASS substitutes the current numerical set point in the <Set Units> for the <Set
Unit Variable> to create the final set command.
The set point command(s) is sent each time a new flow increment or set point is initiated in a
COMPASS run mode.
See Section 13 for information on COMPASS remote communications.
Communications
Test
(action button)
This feature is used to test communication with a DUT whose <Set Point Type> is RS-232 or
IEEE-488. Press this button to send the <Initialization Commands> and <Set Commands> to
the DUT. A <Spy Window> will display with the command response information used (see
Section 6.7.7). This feature is designed to provide on the spot troubleshooting of the remote
commands setup. If a command is not properly entered or the response format is not correct, the
problem should be visible in the spy window. Use the
[Remote Communications] tool for
further troubleshooting (see Section 13.6).