VIM-1 Spinning rotor gauge




  • Measurement range from 1.0E-6 to 10 mbar (7.5E-7 to 7.5 Torr)

  • Easy to use by one-button operation

  • Excellent long-term stability

  • Digital RS-232 or RS-485 interface

  • Chemical and corrosion resistant sensor

  • Bakeable all-metal sensor design

  • Low-cost disposable sensor

  • Passive high vacuum sensor without ion- or heat source 

VIM-1 Spinning rotor gauge instrument

The VIM-1 instrument is based on a robust spinning rotor gauge vacuum sensor that measures the pressure-dependent molecular drag on a magnetically levitated spinning steel ball.

Spinning rotor gauges have been used for decades as transfer standard precision instruments in metrology vacuum calibration applications. The VIM-1 takes the spinning rotor gauge technology to industrial applications, where static vacuum needs to be measured and verified. The low-cost sensor design can be integrated in customer equipment, and the instrument and measuring head can be used to operate multiple sensors.

The VIM-1 is available as a stand-alone spinning rotor gauge instrument or as a full-range package combined with a VPM-5 SmartPirani™ vacuum transducer for PC interfacing via USB interface.

Spinning rotor gauge sensor technology

The spinning rotor gauge sensor device consists of a steel ball inside a tube. The sensing head includes the surrounding electronics and coils to drive and measure the steel ball rotation.

  1. Sensing ball levitation coil
  2. Sensing ball element
  3. Sensor tube
  4. Rotation driving coil
  5. Permanent magnet
  6. Measurement coil
  7. Damping coil
  8. Vacuum flange

Spinning rotor gauge head explained
Spinning rotor gauge full-range system

Measurement performance

During the measurement loop the magnetic driving coil accelerates the spinning steel ball to 660 rps (rotations per second) after which the driving coil is de-energized. The measurement coil then measures the rotations of the ball during the deceleration time period. The deceleration rate of the ball is a function of the pressure-dependent molecular drag. The spinning rotor gauge measurement cycle and display update rate can be set to 3, 5, 10 or 20 seconds.

Full-range system

The VIM-1 full-range system comes with a VPM-5 SmartPirani™ transducer that adds the following features:


  • Full range measurements from 1E-6 mbar to atmospheric pressure.
  • Pirani and Piezo measurement provides faster response 
  • Safe operation of the VIM-1, making sure that it is only operated at supported pressures.

VIM-1 Spinning rotor gauge applications

The low-cost, all-metal VIM-1 sensor element can be integrated in customer vacuum systems and requires no electrical vacuum feedthrough. It is hermetically sealed and can be exposed to both high bake-out temperatures and corrosive gasses. The spinning rotor gauge sensor element is passive and does not generate any ions or thermal emission like traditional wire Pirani or hot/cold cathode gauges.


Cryogenic and liquid gas vessels

In many industries, cryogenic liquids such as liquid oxygen, nitrogen and argon are stored and transported in specially designed cryogenic tanks. A cryogenic tank is insulated with a double-wall vacuum cavity where it is critically important to maintain an adequate vacuum level of typically <1×10-2 mbar.

Integrating a spinning rotor gauge sensor head in a cryogenic tank enables verification of the insulation without breaking the vacuum.


Vacuum insulation panel (VIP)

Vacuum cavities are used as insulation in a wide range of applications.

Quality check of vacuum pressure inside vacuum insulation panels requires in-situ measurements using embedded sensors. The VIM-1 sensor ball element can be integrated in insulation vacuum panels for verification – ensuring adequate vacuum pressure levels and insulation properties.


Another vacuum insulation application where continuous verification of the vacuum level can be beneficial is vacuum insulated glass (VIG). 


Rate-of-rise outgassing testing

In the spinning rotor gauge sensor, the only material exposed to the vacuum gas media is stainless steel and its passive sensor design makes it ideal for outgassing and leak testing by use of the rate-of-rise principle.

Do you have questions or need help configuring the right products?

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