OTP-W - Fiber optic temperature sensor

Robust measuring tool to monitor temperature in extreme conditions in Oil & Gas Applications

Pure monocrystalline

Opsens Solutions’ OTP-W fiber optic temperature sensor offers the highest performances in the industry. The sensor uses the temperature-dependent birefringence of specially selected crystal as the temperature transduction mechanism. Because of the pure monocrystalline material used, the OTP-W does not shows thermal creeping or aging as with other fiber optic sensors based on the thermal dilatation of glass optical fibers.

Combined with Opsens Solutions’ WLPI signal conditioning technology and with the inherent advantages of fiber optics, the OTP-W delivers unprecedented repeatability and reliability in the most adverse conditions such as high level of EM, RF, MR and microwave field environments as well as with high voltage and rapid temperature cycling conditions.

The standard operating range of the OTP-W is from -40 °C to +300 °C. High resolution and accuracy versions are also available for smaller range.

The OTP-W is compatible with all Opsens Solutions’ WLPI signal conditioners. This compact and robust fiber optic temperature sensor, available in different cables and sheath options, is customizable according to customer specific applications or for OEM-type application:

  • High temperature environments
  • Industrial process-control and monitoring applications
  • High voltage environments
  • Hazardous environments
  • Oil & Gas applications
  • Temperature measurements conducted in confined spaces, hazardous or strong EMI/RFI/MRI environments

Key features

  • Robust design
  • EMI/RFI immunity; intrinsically safe
  • Outstanding repeatability
  • No shift over time, high stability
  • Small size (4 TO 6 mm with housing)


  • Downhole sensing solutions
  • Natural gas extraction (CBM & CSG)
  • Downhole monitoring in thermal EOR (Enhanced Oil Recovery)
  • Intelligent and smart field instrumentation
  • Storage and transportation
  • Pressurized environment
  • Refining processes
  • LNG (liquefied natural gas)
Temperature operating range

-40 °C to +300 °C


0.1 °C


± 1.5 °C (-40 °C to +300 °C) – @ ± 3.3 sigma limit (99.9% confidence level)

± 0.8 °C (-40 °C to +250 °C) – @ ± 3.3 sigma limit (99.9% confidence level)

± 0.5 °C (-20 °C to +120 °C) – @ ± 3.3 sigma limit (99.9% confidence level)

Operating humidity range

0-100 %

Cable length

up to 3000 meters

Optical connector

SC standard (other connector avaliable)

Cable sheathing

Customers specifications – from  polyurethane to stainless steel

Signal conditioner compatibility

All Opsens Solutions’ WLPI signal conditioners

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

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