Fiber Optic extensometer sensor with anchors

For Concrete & Steel Structures Monitoring

Based on Opsens Solutions’ unique WLPI signal conditioning technology (Patent # 7,259,862) and the inherent advantages of fiber optics strain sensor, the robust extensometer is designed to provide a 100% survivability. The unique properties of the WLPI Technology makes it insensitive to temperature variation and an outstanding repeatability. Monitoring aging buildings or integrating smart instrumentation in critical infrastructure is common practice. Especially for concrete constructions, subject to cracking and material deterioration over time.

Built in robust alloy, these sensors can be used in demanding environment exposed to high voltage, radiation, or EMI. They can be packaged for marine environment, and even in applications where sensors are permanently exposed to sea conditions such as concrete dock, wharf, and offshore platform. Since they don’t drift over time and maintenance is not required, they can be used in surveillance applications which last for decades.

The fiber optic extensometer can be used to monitor single crack or group of concrete fissures through its long base version. The span could reach meters if needed to optimize surveillance of grouped fissures. A version is also available to be welded on steel structure.

Intrinsically safe, these sensors are the obvious choice for hazardous environment such as those having explosive atmosphere and under ATEX directive.


  • Maintenance free without drifting over time
  • Outstanding repeatability
  • No temperature compensation required
  • Insensitive to transverse strains
  • Intrinsically safe
  • Easy to set-up and operate
  • No Lag – No Latency


  • Civil engineering and geotechnical applications
  • Marine and subsea conditions
  • High voltage environments
  • High temperature applications
  • Nuclear and hazardous environments
  • ATEX environment and zone exposed to explosive atmosphere
Measuring range (other ranges available on request)

-1 000 µε


 +1 000 µε

-2 500 µε


 +2 500 µε


0.15 µε

Temperature sensitivity


Temperature strain range


Temperature operating range

-40°C to +60°C (other temperatures available on special request)

EMI/RFI Susceptibility

Complete immunity

Cable Lenght

Up to 3 km (Sampling rate dependent, consult factory for more details)

Optical connector

SCA (Standard), SC (Standard), other connector available on request

Signal conditioner comptability

All Opsens Solutions’ WLPI signal conditioners

External casing

Stainless Steel 316L

Linearity, repeatability and hysteresis error (combined)

< 0.15%

Return to initial strain level (Lag & Latency)


Opsens Solutions Inc. reserves the right to make any changes to the above specifications without prior notice.

Do you need help to find your optic extensometer ?