VACOMASS®  flow meter

  • Thermal dispersion air mass flow meter 
  • Direct measurement of flow at standard conditions (Nm³/h, scfm)
  • Stainless steel sensor without moving parts
  • Robust, wear- and service free, no pressure loss 
  • Dynamic response ideal for monitoring, totalization and control
VACOMASS Flow meter

VACOMASS® flow meter

The air flow meters of the VACOMASS® series are based on the principle of thermal dispersion and directly measure the mass flow or the airflow at standard conditions, independent of the temperature and pressure of the medium. Temperature compensation is a standard feature.

The VACOMASS® flow meters are remote transmitters for measuring aeration air at temperatures up to 1300C (2650F) and pressures up to 10 bar (145 psi).
The dynamic response of the system is ideal for monitoring, totalization and control.  Constant accuracy is easily maintained over a measurement span of 1:100. Repeatability is better than +/-0.15% of the measured value.

The accuracy of the instrument depends on the installation and the flow profile at the installation point. If the straight pipe run in front of and behind the sensor is insufficient, or if the flow is disturbed by fittings or other installations, the probe should be placed directly in front of the control valve. Depending on the type of valve and the required measurement accuracy, a correction of the signal based on valve position (real-time stroke compensation) may be necessary. This can occur either directly in the sensor head (Model AL100) or in a separate electronic module VACOMASS® flexcontrol.


The following models are available:
VACOMASS® flow meter SS:  The electronics are located in a compact, pressure-rated stainless steel body (SS 1.4571/316Ti) with a sealed connector box. An integrated display is an option.
VACOMASS® flow meter AL:  The electronics are located in a compact aluminium body. An integrated display is an option.
VACOMASS® flow meter AL DIN:  The electronics are located in a compact aluminium body.
VACOMASS® flow meter AL 100:  The electronics are located in a compact aluminium body. An integrated display is an option. The unit has an analog input for the position signal from the control valve, to allow correction of the raw flow signal (stroke compensation) to achieve an accurate flow measurement.
VACOMASS® flow meter multi:  In large diameter pipes it might be advisable to install several flow sensors at various installation depths to capture a weighted average value for correct measurements in uneven flow profiles. All sensor models (SS, AL, AL DIN) can be used. The VACOMASS® flexcontrol module processes the signals.


Hot tapping units with ball valves for installation in existing pipes are available. There are two models:

VACOMASS® OEIN-S: Hot tapping unit with manual ball valve and variable insertion depth
VACOMASS® OEIN-F: Hot tapping unit with manual ball valve, fixed sensor insertion depth and fixed sensor orientation