Technology

The LIOS temperature and strain monitoring solutions from NKT Photonics are based on using passive optical fibers as distributed sensors, whereby we can deliver continuous and accurate monitoring of temperature and strain over long distances or large surfaces. The LIOS systems are not only the safest solution but also the most cost-effective for large installations.

Many conventional technologies face issues with harsh surroundings and operating environments, but the LIOS technology is immune to vibration, electromagnetic noise, dust, cryogenic temperatures, and moisture so no matter the challenge, our robust fiber optic sensor can withstand it.  The LIOS technology has been proven in critical applications like fire detection in road and rail tunnels, special hazardous buildings, power cable and aerial transmission line monitoring, in oil & gas exploration, and for industrial induction furnaces surveillance.

Our LIOS product series was carefully designed and thoroughly tested targeting reliable performance and accurate temperature monitoring over long distances or large areas in industrial environments. Excellent Mean-time-between-failures (MTBF) of more than 28 years was obtained based on the latest statistical field analysis of our LIOS product series.

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 system.

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.