Name: os5500 Long Range Displacement Gage, FBG-Based Fiber Optic Displacement Sensor
Brand: Luna
SKU: os5500

Overview

The Luna os5500 is a displacement gage based on fiber Bragg grating (FBG) technology. It measures displacement between two gage points on a specimen surface, with a measurement range of up to 450 mm, and is intended for civil and geotechnical structures. The gage design allows attachment to various substrates, including metal and concrete surfaces.

The FBG sensors that make up the gage are housed in a hard-coat anodized aluminum enclosure, which shields them from the elements and allows installation in harsh environments. Cables can be joined directly inside the enclosure, which removes the need for separate junction boxes.

The os5500 can be used alone or in series as part of an FBG sensor array that may also include strain and temperature gages, accelerometers and other displacement gages. Cabling for such arrays is less expensive and less cumbersome than for comparable electronic gage networks, and like other FBG-based sensors the gage is immune to electromagnetic interference, which vibrating wire gages are not.

Each gage is supplied with a Sensor Information Sheet listing the gage factor and calibration coefficients needed to convert wavelength information into engineering units. Luna's ENLIGHT Sensing Software provides a utility to calculate, record, display and transmit data for large sensor networks. The gage is used with Luna HYPERION interrogators.

Key Features

Up to 450 mm measurement range using a 1 mm stainless steel cable
Rugged aluminum enclosure with IP65 rating, suitable for outdoor installations
Internal protection of connectors/splices
Double-ended design supports multiplexing of many gages on one fiber
Fully temperature compensated over the entire operating range
Fast response time, stable measurements, high resolution
Qualified to the same standards used for comparable electronic gages
Designed for simple installation in a variety of applications

Specifications

Performance Properties

Displacement Measurement Range	150 mm, 300 mm, or 450 mm Does not include overtravel. For the 150 mm, 300 mm, and 450 mm options overtravel is 310 mm, 160 mm and 10 mm respectively
Resolution	0.02% F.S. Full scale at room temperature, measured on a calibrated displacement stage using a Luna sm130
Linearity	< 0.4% F.S. Based on nominal performance
Repeatability	± 0.05% F.S.
Operating Temperature Range	-40 to 80°C
Environmental Ingress	IP65
Fatigue Life (Tested to)	16 x 10^6 cycles at 63 mm stroke
Temperature Dependence	0.006%/°C F.S.

Physical Properties

Dimensions	190 L x 175 W x 90 H mm
Weight	< 3.1 kg
Material	Hardcoat anodized aluminum
Wire Pull-Cable Length	2 m with 6 mm loop termination
Fiber Optic Connection	Internal to gage, accepts cables between 3 to 7 mm diameter
Fastening Method	Bolt-on, two 8.8 mm dia. holes

Optical Properties

Peak Reflectivity (Rmax)	> 70%
FWHM (-3 dB point)	0.25 nm (± .05 nm; apodized grating)
Isolation	> 15 dB @ ± 0.4 nm around center wavelength

Ordering Information

Part number format	os5500-rrr-wwww/wwww-1xx rrr = range, wwww/wwww = wavelengths, 1xx = length and termination; example os5500-300-1521/1523-1FS
Standard wavelengths (+/- 1.5 nm)	1476/1478, 1491/1493, 1506/1508, 1521/1523, 1536/1538, 1551/1553, 1566/1568, 1581/1583, 1596/1598, 1611/1613 Bandwidth allocation requires an additional -6 and +7 nm
Standard fiber lead length	1m

Specifications are taken from the manufacturer's documentation. See the datasheet for complete and current values.

Options & Accessories

Option	Description
150	150mm range — Range code rrr in os5500-rrr-wwww/wwww-1xx
300	300mm range — Range code rrr in os5500-rrr-wwww/wwww-1xx
450	450mm range — Range code rrr in os5500-rrr-wwww/wwww-1xx
FC	FC/APC Connector — Termination code xx; standard length is 1m
FS	Fusion Splice — Termination code xx; standard length is 1m