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Active Measurment Gauge


Pirani / Pirani & piezo transmitters


We have three main variants of the THERMOVAC TTR Pirani gauge product line, all of which are well suited for measurement in rough to medium levels of vacuum, and to combine with our high vacuum/ultra high vacuum gauges such as the PTR or the ITR product lines (LINK). They are found in basically every vacuum system due to their wide measuring ranges, compact size and cost efficiency. 

Leybold THERMOVAC Pirani gauges are long established in the vacuum market and have been used for decades alongside our vacuum pumps. 

The flexibility to select a model that meets your process needs, both from a vacuum performance viewpoint and a connectivity viewpoint, is key for many customers. We provide further peace of mind by being fully compliant with all relevant international regulations.

Leybold has been backed by our skillful applications and technical teams, who can pull on our experience serving many vacuum markets to help you choose a measuring solution that is fully proven for your application.

Using Leybold THERMOVAC gauges can increase your process efficiency while saving on your spending by combining them with our pumps, such as the ECODRY series, to offer optimized pumping performance. 

You can also use our THERMOVAC gauges to reliably control and optimize your process, reduce cycle times, spot errors and prevent unexpected downtime by monitoring and triggering processes, or by halting a process if the correct vacuum levels have not been reached. 


The standard Pirani gauge

Able to measure from atmosphere to 1e-4 mbar it covers the crucial pump down range for most processes. The sensor design is reliable across all applications, with a proven track record. The 360°C light ring gives you a visible indication of the gauge status from wherever you are: a useful feature when operating on large installations where you may not be near a HMI port. 

Active Measurment Gauge

We offer basic stripped-down versions, alongside versions with more features: Set point relays as well as specific corrosion resistant variants. We also propose multiple types of output: standard 0-10v linear analogue outputs as well as more modern digital outputs, well suited for integration into a PLC.

THERMOVAC TTR 101 series

For pressures above 100 mbar

A weakness of standard Pirani gauge is their low ability to accurately measure at pressures above 100 mbar (75 torr). This is solved with the premium THERMOVAC offering: the TTR 101 range combines the Pirani filament with a miniature capacitive manometer, where the capacitance sensing element covers the initial rough vacuum range. The pressure measuring range of this upgraded vacuum gauge is 1500 mbar (1125torr) t  5x10-5mbar (3.75x10-5 torr). 


These gauges are available with a linear analogue 0-10v output or with digital (RS232/485) and EtherCAT outputs, giving you flexibility to choose the best communication method for your system. We also have variants with an integrated display giving you a direct way to read the pressure away from a central controller.

THERMOVAC TR 2* series

Our passive gauge offering

Another standard pirani gauge, the difference being that this gauge is our passive gauge offering.

The gauge electronics have been removed and are kept in a separate gauge controller. It retains all the benefits of a TTR9* with a wide measuring range (atmosphere to 5e-4).

As they have no electronics there are no features on the gauges themselves: these are on the separate controller, check out the COMBIVAC (LINK) for more details!

  • Measurement signal insensitive to mounting position 
  • High overpressure limit (10bar)
  • TTR series available with LED ring and up to two set point relays for improved process control 
  • Optimized price-to-performance ratio
  • Highly reliable and repeatable fore vacuum and high vacuum pressure measurement 
  • Usable with cable lengths of up to 100m, ideal for large installations.  
Broad Range Vacuum Gauging
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