Agilent Technologies Helium User Manual page 74

Technical Information
Read Internal Leak
Full Calibration
(Internal Only)
Fast Calibration
* If the system cannot read the internal calibrated leak temperature, the system
displays the leak value and the temperature shown on the calibrated leak label. If
this happens, the calibrated leak symbol on the main screen turns red.
External Calibration defaults to Fast Mode only.
NOTE
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Opens the Internal leak valve so the leak can be seen by the
system.
The Read Internal Leak button is only functional while the
leak detector is in Test/Fine test and activates the internal
calibrated leak, allowing verification of the system
calibration. When the system is in Std Leak mode, Std Leak
appears on the Home screen.
The Std Leak mode isolates the test port from the system
and exposes the leak to the spectrometer. This allows you
to compare the displayed leak rate value to the calibrated
leak value on the Calibration Menu screen to verify proper
system operation.
Because the test port is isolated from the fore pump in this
mode, a slight increase in test port pressure may be
indicated on the test port pressure display.
Performs a thorough tuning process and a system gain
adjustment (calibration). The full tuning process involves
scanning the ion source chamber voltage, and optimizing
each value for a maxi- mum helium signal. Once the tuning
process is complete, system gain is adjusted to bring the
leak detector into calibration. A full calibration takes less
than three minutes.
Compares the leak rate signal with the calibrated leak value
and adjusts the gain to bring the system into calibration. If
the gain value is above the upper gain limit for the working
range as defined in the following table, then the fast
calibration process is terminated and a flashing c symbol
appears on the Home screen. A fast calibration takes less
than 30 seconds.
Agilent Helium Leak Detector User Manual