Optimized for outdoor installations on steel structures, the os3155’s stainless steel carrier holds the FBG in tension and protects the fiber during installation. Since there are no epoxies holding the fiber to the carrier, long term stability is ensured by design.
The design is similar to the os3150 rugged strain gage but the os3155 includes a second FBG which provides active temperature compensation. The benefits of this approach include both more accurate temperature compensation (since the strain and temperature measurements are made in close proximity) and lower-cost installation (by reducing the need for additional cables, splices and handling to connect additional temperature gages).
The sensors can be installed in just a few minutes. Since the gages are welded in place, they can be used immediately after attachment without waiting for adhesives to cure. Armored cables lead to and from each gage, making both installation and fiber protection fast and easy. Optional protection fittings help prevent damage to series connections even in harsh environments. This enables fast reliable field connections to other optical strain, acceleration or temperature sensors on the same fiber. The entire strain gage package is typically covered with a protective material to complete installation for long term protection.
In side by side comparisons with foil strain gages, the os3155 is equally sensitive and accurate, while providing for greater strain range and 100 times more fatigue life. The os3155 strain gage is qualified for use in harsh environments and delivers the many advantages inherent to all FBG based sensors.
This sensor can be used alone or in series as a part of an FBG sensor array. Installation and cabling for such arrays is much less expensive and cumbersome than comparable electronic gage networks. Multiple optical strain gages can be arranged in close proximity at 0, 45 and 90 degrees for strain rosette measurements.