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VSA100A diff. to ambient

The INFICON Vacuum Switch VSA100A is used as a safety switch in vacuum systems. For example, to automatically interrupt the gas supply when venting vacuum systems with a purge gas at a pressure of 6 mbar below atmospheric pressure. At a differential pressure of 6 mbar resp. return switching pressure of 3 mbar below atmospheric pressure, an elastic diaphragm actuates a changeover contact which in turn may be used to switch directly any ancillary equipment.


  • Reliable and budget-priced vacuum switch
  • High life time
  • Rugged design
  • Easy to integrate
  • IP 44 protection

Typical Applications

  • Control of load lock chambers
  • Safety shutdown of vacuum systems

Part Number

Part Number Description
399-001 VSA100A Vacuum Switch DN16KF, 3m Cable




Type VSA100A
Switching pressure mbar 6 ±2 (below atmosphere)
Back switching mbar 3 ±2 (below atmosphere)
Operating pressure (absolute) bar <2
Helium permeation mbar•L/s <10-6
Leak rate mbar•L/s <5 x 10-8
Operation °C 0 … +85
Storage °C -20 … +85
Switching contacts (Change over contact, gold plated)
Voltage max.  24 VDC
Current max. mA 30 (24 V(dc)) / 100 (24 V(ac))
Load min. mA 1
Electrical connector cable, bare wire
Cable length, standard m (ft.) 3 (9.9)
Vacuum connection DN 16 ISO-KF
Protective type IP 44
Mounting orientation vertical (standing)
Internal volume cm³ (in.³) 2 (0.122)
Materials exposed to vacuum stainless steel 1.4305, EPDM, PTFE (Teflon)
Weight g 315
Technical Note: Due to the diaphragm material used (EPDM) the Vacuum Switch VSA100A is not suited for applications in which the process gascontains large quantities of helium. The leak rate of the diaphragm for helium is -6 mbar l/s.

3D Step Files