Inficon Fab UL6000 Fab, Operating Instructions Manual

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Automatic tuning / mass setting
This function adjusts the mass spectrometer so that a maximum leak rate indicator is
achieved. In order to detect a maximum ion current with the ion detector, the control
computer adjusts the voltage for accelerating the ions within the selected mass range
accordingly.
During each calibration, there is an automatic adjusted.
Operation mode
The leak detector distinguishes between the "Vacuum" and "Sniffing" operation
modes. For the "Vacuum" operation mode, generally the tracer gas flows into the test
object. The pressure in the test object is less than the ambient pressure.
In the "Sniffing" operation mode, the tracer gas flows out from the test object and is
extracted with a sniffer probe. The pressure in the test object is greater than the
ambient pressure.
FINE
FINE designates the connection to the turbo molecular pump for medium inlet
pressures. This is also used for the "Sniffing" operation mode.
Forming gas
Forming gas is a collective term for gas mixtures of nitrogen and hydrogen.
GROSS
GROSS donates the connection to the turbo molecular pump with the lowest
sensitivity. This allows high inlet pressures.
Internal helium background
The measurement system of the leak detector also contains a residual amount of
helium. This creates an internal measurement signal component (background signal),
which overlaps the display of the leak right from the beginning and thus disturbs the
search for leaks.
So that this background signal can be suppressed, an internal "background
suppression" can be activated with the factory settings. When pressing the START
button, the currently internal measuring signal is counted as helium background and
subtracted from the measurement signal. If the leak detector has not been in the
"Standby" or "Vented" mode for 20 seconds, the last used internal helium background
is deducted.
Minimum detectable leak rate
The minimum detectable leak rate that can be detected by the leak detector under
ideal conditions.