Temperature Sensing

Fiber optic temperature sensing: performing measurements under extreme temperature conditions.

Fiber optic temperature sensing supports the international tendency to increase the situation awareness of production or industrial processes. Metal casting, process or chemical industry – wherever temperature plays a major role, fiber optic temperature sensing is a key element of the monitoring system. Improved production efficiency as well as reduced downtime, maintenance and costs are at stake. The solution supports users capitalize on the smart industry 4.0 revolution by ensuring real-time monitoring. Furthermore, it enables connectivity and data analysis.

Fiber optic temperature sensing as turn-key solution.

Our fiber optic temperature sensing solution includes sensor, interrogator, software and data interface, as well as customizable temperature sensing probes, robust cabling with full connectorization, rack-mountable measurement devices as well as the integration of our software for read-out and integration into e.g. an IBA environment.

Our temperature sensing solution is installed within the industrial environment, in the areas to be monitored, meaning directly into the casting molds: DTG®-based temperature sensing fibers are made to be embedded directly into the hot casting zone, enabling space distributed measurements where the available space is limited.

The measurement device is set up in a remote electrical or operation room. Multi-fiber transmission cables, hosting up to 24 fibers each, guide the optical signals from the sensors to the interrogator.

The measurement points per temperature sensing line typically amount to a number between 5 and 60. Equipment for the precise alignment and installation is available to ensure optimal and well-controlled measurement positions.

Recent advancements in fiber optic sensing have made fiber sensors significantly more attractive for industries with highly challenging environments. Fiber optic temperature sensors can multiplex tens to hundreds of measurement points in a single optical line without any compromise on measurement accuracy or reliability. As a result, highly accurate and distributed temperature profiles can be mapped out in real time, stored for further analysis and historic data comparison. Fiber optic temperature sensing offers a high-end alternative to traditional thermocouples as they will never achieve the same level of position resolution. Furthermore, thermocouples need to be replaced more often, which is labor-intensive and expensive. In comparison, replacing the fiber optic sensors is much easier, and in terms of cost per sensing point much cheaper.

System features

∙ Turn-key temperature sensing system
∙ Easy integration in existing systems (IBA compatible)
∙ High mechanical robustness suited for hazardous applications
& industrial environment
∙ Parameters tailored to customers’ needs & requirements
∙ Temperature resistant from -196° to +350°C
(from cryogenic to metal casting environments)
∙ Short response time, detects fast temperature changes
∙ Long distance read-out (over >20 km), no amplification needed
∙ Resist to corrosion
∙ Immune to electromagnetic interferences, passive

Fields of application

Whether it is used in casting plants, in industrial processes or in structural health monitoring, FBGS provide a turn-key solution tailored to the individual requirements of each application.

FBGS’ temperature sensing solution has successfully been integrated in several steel casting plants worldwide empowering the production processes and accuracy. Although this is the main market, other fields of applications are not to be forgotten. For several specific industrial processes, monitoring the temperature is a crucial part of the daily business. Recent advancements in fiber optic sensing have radically changed the way the industry is looking at temperature sensing.

Further application fields for fiber optic temperature sensing solutions are:

Process industry
∙ Manufacturing plants
∙ Oil refineries
∙ Chemical plants

Steel casting industry
∙ Thermal exchange supervision
∙ Steel casting process supervision
∙ Steel casting flow visualization
∙ Break-out detection
∙ Steel quality improvements

Further casting industries

Structural health monitoring
∙ Leak detection
∙ Thermal exchange supervision

Cases for Temperature Sensing

Short example of application in the steel casting industry

ECN is one of Europe's largest energy research organizations, focussed on sustainable energy generation to develop safe, efficient, reliable and environmentally friendly energy systems. It has a strong international position in the fields of biomass, solar energy, wind energy, energy efficiency and policy studies.

Indra is a multinational company specializing in Technology Consulting throughout Europe and Latin America. With 550 million invested in R&D in the last three years, they see innovation as their driving force.

Download technical information

Please fill in your information to download more information on our components.


* These fields are required.

How we use your information

We are committed to respecting your privacy and protecting your personal information and will always treat it with the upmost care. You can find out how we handle your data and all the ways we use it to provide you with a better service in our Privacy Statement.

By submitting this form, you consent to the use of your data in accordance with our Privacy Statement.

Contact us

* These fields are required.

How we use your information

We are committed to respecting your privacy and protecting your personal information and will always treat it with the upmost care. You can find out how we handle your data and all the ways we use it to provide you with a better service in our Privacy Statement.

By submitting this form, you consent to the use of your data in accordance with our Privacy Statement.


FBGS Technologies GmbH
Franz Loewen Straße 3
D-07745 Jena


FBGS International NV
Bell Telephonelaan 2H
B-2440 Geel


Suzhou X2 Electronic Technology Co Ltd
Room No. 2003, Building 38, No. 60 Weixin Road, Suzhou Industrial Park
215122 Suzhou, Jiangsu China



Temperature sensing | FAQ

Why is our fiber optic temperature sensing particularly suited for metal /steel casting applications?
Metal casting applications can be considered as one of the most challenging environments in terms of high temperature. While the temperature range easily raise up to several hundreds of degrees Celsius and where rapid changes occur, fiber optic temperature sensing overcomes these difficulties with its unique sensing principle in order to provide accurate temperature measurement.
How / why can FBGS deliver a complete turn-key temperature sensing solution?
Relying on over a decade of experience in the fields of fiber optics, gratings and measurement devices, FBGS combine both technology and application know-how to achieve complete sensing solutions. The FBG-Scan unit, a spectrometer-based FBG device, features polarization insensitive measurement (low DOP broadband light source) and high scanning frequency (up to 2 KHz). This interrogator is a perfect match to TC-X01 temperature sensor. In the end, FBGS will be able to supply you from the sensor and its suitable packaging all the way to its measurement device and the user-friendly read-out interface. Moreover, we invest in research and development to keep improving our sensing system and tailor it to specific applications needs.
Can the fiber optic sensors be embedded, and how?
The fiber optic cables are made to be directly embedded in the structures or elements that they need to monitor. Special capillaries have been developed for that purpose. As each application has specific requirements, embedding techniques need to be discussed and tailored in accordance with these needs.
Which technologies are best suited for fiber optic temperature sensing?
Scan 90X-EP: The all new FBG-Scan 90X-EP interrogator supports up to 15 optical channels with up to 60 sensors each, enabling 900 temperature sensing points per instrument. It combines high measurement accuracy with enhanced connectivity and data streaming capability. Furthermore, a dedicated developed API enables remote maintenance and control. Software tools are available to integrate the data within widely used measurement software platforms, such as IBA. Fan Out Box: The multifiber fanout box allows for a simple and cost-effective installation of multiple transmission lines at remote locations, even up to kilometers away from the sensing area. The construction of multipoint installations with easy to use and reliable connection points will be possible. TC-X01 With our own developed TC-X01 multipoint temperature sensor chain it is possible to measure up to 60 temperature points with only one sensor. This sensor has a high sensitivity and can be used from -200°C up to 350°C. The multipoint sensors are suited to monitor, control and optimize process conditions for example in steel molds, chemical reactors and energy storage facilities.
How does the sensing solution compensate the cross-sensitivity with strain?
To eliminate the effect of strain and therefore the existing cross-sensitivity with strain, the fiber is integrated in a capillary for protection. The tube is usually made of stainless steel, for example in the case of the sensor TC-X01. For special applications the tubing can be made of glass or ceramic. The capillary transfers the temperature from the structure to the fiber without influencing it and at the same time protects the fiber from the strain experienced by the structure during the temperature shifts. Due to specific properties the stainless tube also protects the fiber against micro-strain that happen through friction between fiber and tube, when made of PTFE.