DH Instruments FPG8601, Руководство по эксплуатации и обслуживанию

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FPG8601™/VLPC™ OPERATION AND MAINTENANCE MANUAL
© 2007 DH Instruments, a Fluke Company Page 70
LABEL DESCRIPTION
Apply thermal
transpiration
correction
Check this box if the DUT requires a thermal transpiration correction. Refer
to the DUT instruction manual for details on whether or not the DUT
requires a transpiration correction. Thermal transpiration is an absolute
pressure measurement mode phenomenon that effects DUTs that are
heated significantly above ambient conditions for normal operation. The
effect becomes significant at 100 Pa and peaks at approximately 10 Pa.
See Section 11.3.4 for details on how the correction is applied. The value of
the correction ratio displays real time on the
<Run Diagnostics>
display.
DUT temperature
for thermal
transpiration
correction
The steady state temperature of a DUT that requires a thermal transpiration
correction. This temperature is used to determine the DUTs thermal
transpiration correction when the correction is active.
DUT orifice
diameter
The minimum connection tube diameter between the DUT and the
FPG8601. This value is typically a diameter internal to the DUT.
Enable VLPC
(check box)
Check this box to use the VLPC to control the FPG pressure. When
checked the
<VLPC Interface>
display is enabled and available for use.
Uncheck this box to use a pressure controller independent of the FPG.
This option is automatically checked if a test sequence is selected that uses
automatic pressure control and is unchecked if the sequence uses manual
control.
Vacuum
Reference
Options
(list box)
This list box allows selection of the three modes of use of the FPG vacuum
reference sensor.
The output of the vacuum reference sensor is not useful in
gauge mode because ATM is significantly greater than the full
scale value of the sensor. Therefore, all vacuum reference
pressure options have no bearing on gauge mode operation.
Use vacuum reference sensor for absolute mode correction -
This is
the most typical use of the sensor. In absolute mode testing, a vacuum
reference pressure device is required to define the absolute pressure from
the FPG calculated differential pressure (see Section 2.8). The device
output displays in the
<Vacuum Reference Prs>
field on the
<Diagnostics
Display>
during absolute mode operation.
Use vacuum reference sensor for data logging only -
The output of the
vacuum reference sensor is logged in the FPG data file and displayed on
the
<Diagnostics Display>
. However, the value is not used to convert the
FPG differential pressure into an absolute pressure. This is the desired
selection for absolute differential mode operation. The vacuum reference
pressure can be used for thermal transpiration corrections and determining
vacuum stability while testing.
Disable vacuum reference sensor -
Use this option when no vacuum
reference sensor will be used by FPG Tools. "0.0" is logged in the FPG
data file and displays on the
<Diagnostics Display>
. Using this feature in
absolute mode induces an error of several Pa depending on the vacuum
pump.
FPG RS232
Settings
The COM port and RS232 settings of the FPG. This selection must be
selected and saved before FPG Tools can interface with the FPG. By
default the FPG will use the RS232 settings 19200, N,8,1. The serial port
used to connect the FPG is dependant on the PC used to run FPG Tools.
6.6.2.2 <OPTIONS>
The options tab allows selections related to automatic functions within FPG Tools
and the optional DUT manifold.
Table 17 describes the features on this tab.