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 82
Figure 39. <Internal Limits> <VLPC>
Table 26. <Internal Limits> <VLPC>
Options
LABEL DESCRIPTION
Minimum hold
setting
(numeric entry field)
The smallest percent of range value that can be used for the hold criterion in
the specified pressure measurement mode. FPG Tools generates a
warning message if a hold limit smaller than this value is setup in a test
sequence or in the
<Settings>
option.
Minimum
pressure for hold
criterion (Pa)
(numeric entry field)
The minimum pressure that can be used as the hold limit in the specified
pressure measurement mode. Attempting to control a pressure below the
resolution of the FPG can make it impossible to obtain a “Ready” indication.
Maximum
pressure, range
multiplier
(numeric entry field)
The value entered multiplied by the active VLPC range determines the
maximum allowable system pressure. The idea is to protect sensitive
DUT's from overpressurization. In most cases, the value should be 1.1.
This allows a 10 % overshoot of the active VLPC range. When the pressure
limit is exceeded, VLPPS Tools automatically vents all system pressure and
connects the test and reference ports of the VLPPS to remove any
differential pressure. Some DUT's may require a small portion of the active
VLPC range. In this case, use a multiplier less than 1 to effectively limit the
useable range.
The VLPC does not significantly overshoot pressure. However, loss of
the VLPC valve pressure supply can cause an increase in pressure beyond
the range of the VLPC.
Without this limit, a DUT would be over pressurized by selecting the wrong
test sequence or by accidentally entering the wrong target pressure value.
Default Absolute
Mode Hold Limits
(numeric entry field)
Each time the VLPC changes to the specified absolute pressure range, the
hold limit specified for the selected range is set by default. The hold limit
can be changed by using the
[Config], [Settings]
option.
Default Gauge
Mode Hold Limits
(numeric entry field)
Each time the VLPC changes to the specified gauge pressure range, the
hold limit specified for the selected range is set by default. The hold limit
can be changed by using the
[Config], [Settings]
option.