The PREVO is a Volume Pressure Regulator (CPV in French) used for measuring ground geomechanical properties according to the cylindrical cavity expansion principle.

Powered by a compressed air cylinder and the auger machine’s battery, the PREVO servo valves automatically adjust test pressure levels. The stress applied (on and between the main bearings) is perfectly controlled by the PREVO operating as a closed loop.

Stress maintenance is perfectly controlled, independently of the reaction of the ground being stressed. The stressing procedure (plateau, duration) is controlled by the operator or automatically by the BAP160 (or the LUBAP) connected to the PREVO (e.g. according to the stipulations of the NF P 94-110 / EN ISO 22476-4 standard).

In this configuration, controlled by the BAP160 or the LUBAP, the PREVO performs the test according to the programmed procedure in automatic or manual mode as selected by the operator. The pressure, volume and time measurements recorded are exploited on a PC by the software EXPRS.





  • Soil investigation
  • Geotechnical, performance of geotechnical tests in situ (NF P 94-110 / EN ISO 22476-4 standard).


Technical features

  • Power supply: 9 -36 VDC, 24 AC.
  • Dimensions (PREVO):  310 x 700 x 380 mm.
  • Dimensions (PREVO100):  260 x 520 x 360 mm.
  • Weight: 27 kg (PREVO), 24 kg (PREVO100).
  • Temperature range: -20°C / +75°C.

Installation diagram