Fibre Optic Piezometer


Fibre Optic Piezometers

The Model 1400 OPP-C Fibre Optic Piezometer manufactured by Opsens Solutions is a MEMS-based alternative to the Vibrating Wire Piezometer (Model 1200). This piezometer is perfectly tailored to meet the challenge of pressure monitoring applications where intrinsic safety is key. HMA Geotechnical have installed Fibre Optic Piezometers within coal mines across Australia, owing to the inherent suitability for this type of application.

The OPP-C sensor delivers long term accuracy, durability, and high-fidelity pressure measurement with a pressure operating range up to 10350 kPa. The sensor is ideal for geotechnical applications. Completely sealed, with a stainless-steel body and diaphragm, the OPP-C is designed to work in adverse conditions of temperature, pressure, and toxic or corrosive atmospheres.
With the inherent advantages of fibre optic technology, it is not subject to interference from electromagnetic interference, vibrations and lightning that might be present in the sensing environment.

The OPP-C pressure sensor is compatible with all Opsens WLPI signal conditioners. The compact and very robust probe can be customized according to specific client needs. The fibre optic cable can be extended up to 3 kilometres long.


  • Geotechnical applications
  • In-situ process monitoring
  • Harsh subsurface monitoring equipment
  • High temperature environment with corrosive chemicals.
  • Groundwater elevation surveillance in wells and streams
  • Pressure monitoring in pumping stations
  • Hazardous environment
  • Static or dynamic pressure measurements conducted under confined space, hazardous and strong EMI/RFI/MRI environments


  • Compact and ultra-robust
  • Excellent accuracy (± 0.2% F.S)
  • Completely sealed for immersed applications
  • EMI/RFI/Lightning immunity for the sensor
  • Rugged stainless-steel body
  • Long term reliability


  • Pressure range (kPa): 172, 345, 690, 3500, 7000, 10350
  • Resolution: < 0.02 % F.S. (Range dependant)
  • Precision: ± 0.2% F.S. (Excluding thermal effect)
  • Thermal coefficient of Zero: < 0.02% F.S / ˚C
  • Proof pressure: 1.5 x F.S.
  • Operating temperature (˚C): -20 to +85
  • Dimensions (mm): Ø 9.5 mm x 117 mm
  • Optical connector: SC standard, others at request
  • Maximum Cable length (km): 3
  • Signal conditioner compatibility: All Opsens WLPI signal conditioners