Previously in this blog, and elsewhere, we’ve extolled the virtues of FBGs — like their small size, immunity to EMI, and resistance to corrosive environments. In a recent paper in the Journal of Power Sources, Nigel A. David and a team from the University of Victoria, Canada have demonstrated the importance of each of these FBG sensor characteristics for their application. David and his colleagues are interested in polymer electrolyte membrane fuel cells. These are thin, flat structures that have an electrochemically active environment inside. David et al detail how others have tried electrical and infrared optical techniques to characterize the performance of PEMs and how these methods come up short. David concludes that using embedded FBG sensors “reliably measure[s] temperature dynamically with a relative resolution of less than 0.2 DEG C,” and is an inexpensive approach that may prove useful for understanding current distribution across the PEM cell.
FBG measurements in this study involved both Micron Optics instrumentation and sensors, specifically the sm130 Optical Sensor Interrogator and os1100 FBGs. See the full paper at: Science Direct
Micron Optics has just released v1.0 of our ENLIGHT Sensing Software. Users have been enjoying Beta versions of ENLIGHT for more than a year, and they have been offering suggestions for new features and improvements. We’ve incorporated many of these ideas in this major upgrade to ENLIGHT.
ENLIGHT allows users to get their sensor systems up and running in just a few minutes. The process begins with defining all of the instrument settings in the Acquisitions Tab and then quickly creating FBGs and sensors in the Sensors Tab (using new automated tools and templates). The Save Tab provides greatly enhanced flexibility to save select sensor information based on triggered events, timed intervals, file sizes, etc. All of these ENLIGHT functions are greatly enhanced with new ease-of-use features. This makes it easier than ever for ENLIGHT to perform all the signal conditioning to output what users need — data in terms of strain, temperature, pressure, acceleration, displacement, degrees of tilt, etc. See more about ENLIGHT at ENLIGHT’s new Facebook page. Or download this free software to see for yourself.
More Good News for LabVIEW Users.
ENLIGHT’s Charts and Images provide easy to use basic data disply options. However, many FBG sensor users want more data display and analysis flexibility. ENLIGHT can also accomodate this. The Remote Command Interface (RCI) allows you to run ENLIGHT in the background as you stream forward the sensor data you want to display. You can use any environment you wish to make the exact charts you want. There is a LabVIEW RCI example included in the ENLIGHT download. (The RCI can also be driven from other programming envoronments like C++ and Visual Basic.)
Since developing our first FBG sensor interrogator in 1996, Micron Optics engineers have used LabVIEW as the primary tool for building user interfaces, and we’ve shipped LabVIEW examples with every instrument. Now the true LabVIEW experts at National Instruments (NI) have created drivers for Micron Optics’ most popular platforms — the sm125 and sm130 Optical Sensor Interrogators. With these new drivers, Micron Optics’ interrogator users have more tools than ever for creating custom user interfaces in LabVIEW. Find out more here:
Most fiber Bragg grating (FBG) sensors are stable and robust in wet, corrosive and high EMI environments, and many work well over a broad range of temperature, e.g., -200 to +275 °C. But above 300 °C, the fiber coating materials, and the FBGs themselves, are subject to degradation and failure.
So what can be done at high temperature? I’ve written earlier about development of special gratings that can measure temperature to 1000 °C, but we’ve seen nothing for measuring strain at high temperature — until now.
Mercury Sensor Systems, LLC of Austin, Texas has recently developed just such a sensor called the Vulcan 1100. Using the Micron Optics’ standard os3120 strain gage as the base sensing element, Mercury’s patented special mounting system allows the FBG in the os3120 to operate below 200 °C while precisely transferring the strain to the FBG. A second FBG sensor (a Micron Optics os4210), integrated in the same package with the strain gage provides active temperature compensation. The Vulcan’s rugged package makes it ideal for its target applications in petroleum and chemical processing.
Find details at (http://www.mercurysensor.com/) or contact Pat Doggett at patrick.doggett@mercurysensor.com.
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