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Hot cathode Bayard Alpert


Our IONIVAC gauges series, whether passive (IE) or active (ITR) offers the ability to measure into ultra high vacuum. This enables detailed tracking of experiments, and control of the variables in processes. 

IONIVAC hot cathode gauges work by having a hot cathode emit electrons which impinge on an anode. The measured gas is thus ionized. The resulting positive ion current is detected through the third electrode and this current is used as the signal which is proportional to the pressure. 

The hot cathode ionization sensors offer a wide measurement range of 10-12 to 10-1 mbar (0.75·10-10 to 0.75·10-1 Torr) depending on the type of hot cathode technology used.

IONIVAC ITR90/200 series

Optimized combination transmitter

The IONIVAC ITR is an optimized combination transmitter. The combination of a hot cathode ionisation sensor (utilising the Bayard Alpert method of hot cathode ionisation) and a Pirani sensor enables vacuum pressure measurements from 5 . 10-10 to 1000 mbar (3.75 . 10-10 to 750torr). 

Two main variants are available:

  • ITR 90 with single hot cathode filament
  • ITR 200 with dual filaments to increase the lifespan via inbuilt redundancy. It will automatically switch filaments in the event of failure and indicate that a filament has failed. To further increase the gauge life, it is possible to run a degas program which can re-invigorate the filaments performance. 

With both types of IONIVAC ITR we have analogue, Digital and Profibus interfaces available, as well as optional integrated displays for local pressure displays. 

When carrying out service on these gauges, the calibration of the sensor is kept on the gauge head, so when replacing the tube, the gauge is pre-calibrated and will be accurate immediately rather than requiring any zero/atmosphere calibration.

You get:

  • Continuous pressure measurements from 1 . 10-10 mbar/torr to atmospheric pressure  
  • Compact design with exchangeable cathodes and degas mode 
  • Bakeable sensor to enable UHV measurement 
  • Analogue, display, digital, and profibus interfaces available for simple install 
  • High repeatability within the typical process pressure range of 10-2 to 10-9 mbar  
  • Precise UHV pressure measurements with passive gauging, enabling measurement down to e-12mbar/torr  

IONIVAC IE 414/IE 514 series

Top of the range for UHV measurement

Our IONIVAC IE series gauges are the “Rolls Royce” of ultra high vacuum measurement, with their ultra low base pressure reading and high levels of accuracy. 

Working in tandem with our passive gauge controllers, these are used in environments requiring detailed pressure readings at the lowest levels. 

The passive IONIVAC IE sensors use the hot cathode ionization technology to measure to the lowest pressures. 

  • The IE 414 utilizes Bayard Alpert technology and can measure from 2 . 10-11 to e-2 mbar (1.5e-11 to e-2 torr). 
  • To reach the lowest pressures you need to reduce the X-Ray affect. This is done on our IE 514 series gauge, by utilizing the extractor method of hot cathode ionization. With this sensor technology you can read from 2e-12 to 1e-4 mbar (2e-12 to 7.5e-5torr).
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