Agilent Technologies Helium Leak Detector
DRAFT 12/1
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5.1.2.2 Transfer to Test
The value input and hidden keypad is to the right of the Transfer to Test feature. Use
it to set the pressure at which the system goes into Test.
The Transfer to Test setting can be adjusted to lower values for specific applications.
The limit on the maximum test pressure prevents the operator from inadvertently
setting the leak detector to transfer into test at too high a pressure, which would
result in excessive spectrometer contamination or ion source filament failure.
Figure 5-4 Transfer to Test
Maximum Test
Pressure
Determines the test pressure cross over point at which the system
transfers from Roughing into Test and then into the Contra-Flow
Test mode. In the Contra-Flow Test mode, the gas sample is
pumped through the leak detector and swept across the high vac-
uum pump foreline. The Contra-Flow mode allows for higher sensi-
tivity testing at exceptionally high test pressures.
The maximum test port pressure is 10 Torr.
NOTE
The transfer pressure from the Test mode to the Fine Test mode
is set at 100 milliTorr (1.0E-1 Torr). You may wish to lower that
value under certain circumstances. The mid-stage transfer
pressure limit is adjustable from 1 to 100 milliTorr via an
RS-232 command (see?ML-XFER and INIT-ML-XFER in
Section A “Communications Protocol” on page 139). The
pressure limit is not adjustable using the display.
Press the
value to access
its keypad
