AST2000 & AST4000 – Hydrogen pressure transmitters

The AST2000 & AST4000 sensor series were specifically designed for hydrogen pressure sensing applications. Tested to a variety of hydrogen and automotive standards, the hydrogen series combines the best mechanical design for hydrogen measurement with high performance.

Due to its one-piece design without welded diaphragm there are no possible leak paths and weak pints. Containment is impossible as there are no oil-filled cavities which could fill with hydrogen. The only wetted material is stainless steel 316L.

The transmitters are digitally compensated with ratiometric 0.5 .. 4.5 V, 1 .. 5 V or 4 .. 20 mA output. They are available for pressure ranges of 20 bar, 448 bar and 900 bar. With the high accuracy option the total error band (TEB) can be as low as just 1 % while the burst pressure exceeds the nominal pressure rating by a factor of 5.

Applications include all apparatus which make use of pressurized hydrogen such as fuel cells, hydrogen storage, hydrogen filling stations, test stands or back up power generators.

Types of the AST2000 and AST4000

  • Pressure ranges: 20 bar, 448 bar, 900 bar
  • Output: 0.5 .. 4.5 V ratiometric, 1 .. 5 V, 4 .. 20 mA
  • Process connection: 7/16-20 UNF male, 3/8-24 UNF male
  • Standard or high accuracy EC79


  • Pressure ranges relative to atmosphere: 0.. 20 bar; 0 .. 448 bar, 0 .. 900 bar
  • Wide temperature range: -40 .. +85°C
  • One-piece design
  • All 316L wetted material for optimal compatibility
  • No oil-filled cavities leave no chance for containment
  • Non-welded diaphragm eliminates leak paths and weak points
  • Digitally compensated
  • Krystal Bond™ Technology
  • Accuracy: +/-0.25 %FSO (AST2000) / +/-0.5 %FSO (AST4000)
  • Total pressure error (TEB): +/-1 %FSO (high accuracy option)
  • Compensated temperature range: -20 .. 60 °C (high accuracy option)


  • PEM Fuel Cells
  • Hydrogen Storage
  • Hydrogen Filling Stations
  • Test Stands
  • Back Up Power

For information on prices and delivery times or if you have any technical questions, please contact