Debuting at Sensors Expo (June 28-29, 2017), Micronor and Optocon AG have collaborated to create the FOTEMP1-OEM-MNT; a low cost, small form factor, single channel signal conditioner that seamlessly integrates Fiber Optic Temperature Sensing into any industrial control system, medical instrumentation or other OEM design.
The compact FOTEMP1-OEM-MNT controller works with all TS series fiber optic temperature sensors, a measurement range of -200°C to +300°C, and standard built-in USB, RS232 and SPI interfaces. The product will be demonstrated at Micronor booth 735 at the McEnery Convention Center in San Jose, California.
On Wednesday, June 28, at 11:00am, Micronor will also be presenting a special live product presentation in the Sensors Expo Live Theater titled “Fiber Optic Temperature Sensors Outperform Thermocouples and RTDs in Challenging Environments.”
The FOTEMP methodology is based on the inherent temperature dependence of the Gallium Arsenide (GaAs) band gap. The signal conditioner couples a continuous broadband light source into the sensor’s large core 200µm optical fiber which illuminates a GaAs crystal mounted on the TS series sensor’s fiber tip. Similar to an optical filter, the crystal absorbs wavelengths below its bandgap and reflects the wavelengths above. The transition region between the reflected and transmitted spectrum, i.e. the band gap spectral position, is temperature dependent – shifting about 0.4nm/degree Kelvin. The FOTEMP controller’s internal optical spectrum analyzer interrogates the reflected optical signal, and then outputs the corresponding temperature value.
This absolute measurement technique ensures stable and accurate measurements over long term usage without the need for periodic recalibration. This is one of many areas where GaAs temperature sensors outperform other optical sensor techniques, including fluorescence decay, interferometric and fiber Bragg gratings. Monitoring the internal temperature of oil-filled transformers, with life expectancies of 20+ years, is one example of why GaAs-based temperature sensors are the sensor of choice for high reliability, mission critical applications. This sensing and interrogation method allows for lower cost, greater accuracy (±0.2ºC), and wider measurement range (-200°C to +300°C) compared to other fiber optic sensor techniques.
The product provides a discrete temperature monitoring solution that operates accurately and reliably in challenging environments where electronics-based temperature sensors (thermocouples, RTDs) cannot function. The fiber optic sensor’s entirely non-metallic, passive optical design provides immunity to electromagnetic interference (EMI), radio frequency interference (RFI), microwaves, high voltage, extreme magnetic fields, radiation, chemicals, and explosive atmospheres. In these environments, GaAs fiber optic temperature sensors enable new and unprecedented solutions impossible for electronic sensors.
Typical FOTEMP applications include monitoring temperature inside high voltage transformers and switchgear, MR imaging, semiconductor manufacturing, petrochemical plants, as well as microwave ovens and reactors used in food industry, material processing and bioengineering. The use of low loss optical fiber allows interference-free, remote temperature monitoring up to 2000 meters. Such distances are characteristic of mines, tank farms and downhole applications.
In small quantities, a complete fiber optic temperature measurement system sells for $1349, consisting of the standard FOTEMP1-OEM-MNT (calibrated -40°C to +300°) at $999, and a general purpose TS2-02 GaAs fiber optic temperature sensor at $350. OEM discounts are available. Typical lead time is stock to 4 weeks. An Extended Calibration option extends the low-end measurement range to cryogenic levels of -200°C.