The Distributed Temperature Sensing OFDR technology - with its approved optical components from the telecom industry - enables to provide sophisticated fibre optic temperature surveillance at commodity prices. The applied light source is a modern and durable semiconductor laser diode, instead of a rather complex solid state laser, which powers typically Raman OTDR systems.
The semiconductor laser diode has been critically type tested according the Telcordia GR-468 standard and is fulfilling telecom standards with a medium lifetime of > 25 years. Not only the laser diode has been tested, the entire system was comprehensively evaluated by various independent international bodies (e.g. the Germany VdS, the association of German asset insurers), which includes EMI tests as well as endurance tests at accelerated aging environments.
The LIOS' DTS ( Distributed Temperature Sensing ) technology has been successfully proven in critical applications like fire detection in road and rail tunnels and special hazard buildings, power cable and transmission line monitoring, in oil & gas exploration for permanent downhole monitoring and for industrial induction furnaces surveillance, where these systems have been equipped in worldwide projects with more than 4500 permanent installations since 1997.
Key advantages of Raman OFDR distributed temperature sensing (DTS) systems by LIOS Technology:
Reliable system design with approved key components from the telecom industry
The semiconductor laser diode tested according Telcordia standard GR-468, with medium lifetime >25 years.
The OFDR technology enables to provide sophisticated temperature surveillance at commodity prices
The essential benefits of OFDR technology are the quasi continuous wave mode employed by the laser diode and the narrow-band detection of the optical backscatter signal, whereby a significantly higher signal to noise ratio is achieved compared to conventional pulse technology (OTDR). This technical benefit allows the use of affordable semiconductor laser diodes and electronic assemblies for signal averaging. LIOS' OFDR Raman DTS is classified as a Laser Class 1M Product.
Invariant spatial resolution along the entire sensor length of 1 m or 25 cm even at most remote distances.
The OFDR technology provides an invariant spatial resolution along the entire sensor length, which ensures to identify and clearly measure atypical hotspots or temperature anomalies at early stages, even at most remote distances. This is in contrast to other measurement principles (e.g. laser pulse principle, OTDR), which are sensitive to dispersion effects and therefore affected by a broadened spatial resolution at longer measurement distances; in other words, the hot spot sensitivity of pulse type measurements degrade with a function of distance.
Direct link to SCADA systems and flexible data handling
The embedded communication module of the DTS controller ensures reliable data interfacing on basis of proprietary or customer specific protocols like DNP3, IEC60870-5, IEC61850, POSC WITSML, Modbus (Master/Slave) etc. Multiple third party systems can be addressed at the same time. The onboard data storage module buffers measurement data and initiates data transfer automatically after the communication link was re-established.
International Approvals and Certificates – type tested and accredited
In conscious of the strong requirements being made in the safety market LIOS provides a highly proven product based on the compliance with international quality standards recognised by various independent international bodies like VdS, TÜV Rheinland, EXAM, FM.
Maintenance free and simplified outdoor installation capability
through higher allowed operating temperature range and fan-free DTS unit design
Impressive track record of more than 4500 installations in permanent operation
LIOS Technology distributes its products in various business segments and has partnered up with dominant players in the related applications and geographic regions.