Description and Working Principle
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Description and Working Principle
4.1
Introduction
The UL5000 basically is a helium leak detector for vacuum applications, i.e. the part
under test is evacuated while the test is performed. The vacuum is achieved with a
pumping system that is part of the UL5000. In addition the vacuum can be generated
by pumps with are set up in parallel to the leak detector.
Another operating mode of the UL5000 is the Sniff mode which can only be used
when a sniffer line (See Chapter
) is hooked up.
4.2
Components of the UL5000
The UL5000 is a self-contained unit in a metal housing on wheels. This housing
contains the entire vacuum system and the according power supplies. On top of the
unit is the inlet port and the display.
4.2.1
Vacuum System
The vacuum diagram below shows the major components inside the UL5000:
The mass spectrometer is mainly composed of the ion source, the magnetic sepa-
rator and the ion collector.
Fig. 4-1: Vacuum diagram UL5000
Pos. Description
1
MS: Mass Spectrometer, Helium sensor (180° magnetic field mass spectro-
meter)
2
Turbomolecular Pump (TMP, provides high vacuum conditions in the MS)
3
V1a … V8: Electromagnetic Valves to control the gas flows
4
Scroll pump (provides the foreline pressure for the TMP and pumps down the
parts under test)
5
Inlet Port
6
Booster Turbomolecular pump
V4a
V4b
p
2
V2
MS
V3
V7
p
1
V1b
V1a
V5
p
3
2
4
6
3
