The vacuum pressure range from atmosphere to ultra-high vacuum (UHV) is over 16 orders of magnitude. To cover this range requires more than one sensor type. High vacuum can be defined from the bottom of the milltorr range to 10e -10 torr. Most high vacuum gauge sensors are packaged with a rough vacuum sensor to cover the entire vacuum range. The exception is ultra-high vacuum (UHV) applications where an additional gauge sensor is needed. High vacuum gauge sensors are ionization gauges which can be either hot cathode or Bayard-Alpert cold cathode.
The measurement range is the decisive factor for an appropriate vacuum gauge. The chart below shows the type sensors and models for the pressure range. The corresponding gauge controller is also provided in the chart for the proper sensor.
Penningvac Sensor
Indirect Cold Cathode – Range 1 x 10-8 mbar – 1500 mbar
Ionic Sensor
Indirect Hot Cathode- Range 10-10 to 10-1 mbar
Ceravac Transmitters – Direct Measurement
Ionivac IM540 for UHV (ultra-high vacuum)
Bayard-Alpert Cold Cathode Passive Sensor
These PENNINGVAC transmitters are the perfect gauge for a wide range of applications. Combines a MEMS-Pirani with Penning high vacuum sensor to cover the full vacuum range from atmosphere to high vacuum. Pennivac is an active gauge with input/output a log-linear 0-10V.
Cold cathode ionization after Penning combined with thermal conductivity (MEMS Pirani)
Measurement/display rang
1 · 10-8 to 1000 mbar
The IONIVAC uses a hot cathode ionization with a Pirani sensor for full range display of vacuum measurement. Ionivac can be used on non-combustible gases and gas mixtures within a wide range of pressures. Optionally, the pressure can be displayed on an integrated display. Ionivac is an active gauge with input/output a log-linear 0-10V.
Pirani / hot cathode ionization (Bayard-Alpert) combination
Measurement/display ran
5 · 10-10 to 1000 mbar
The CERAVAC Capacitance Diaphragm Gauge (CDG) direct measurement of an Inconel diaphragm defection to measure vacuum pressure. They are resilient to vibration and pressure bursts and provide good resistance to corrosive process gases.
Capacitive diaphragm stainless steel sensor
Measurement/display range- 10-5 to 1000 torr
Vacuum gauge controller with 1-3 channels for all active sensors. Graphix has a 3.5″ TFT touchscreen interface, easy to read bar graph display and ability to test to detect leaks using a pressure rise test.
Readout selectable between mbar, Torr, Micron, Pascal or Psi
Up to 6 adjustable set points
Internal and external data-logging (USB port on the front) for configuration and real-time measurement data
Sensor control function (degas and zero adjustment)
Selectable languages: English, German, Chinese, Japanese
Bayard-Alpert Cold Cathode
Measurement/display range- 10e-12 to 1100 mbar
