FBG – Fiber Bragg Grating

FBG Interrogator SPK-155: Optical precision

  • high resolution
  • high sensitivity
  • for static and dynamic measurements
  • no moving parts for the spectral analysis
  • read-out of FBG's at arbitrary wave lengths within the spectral range
  • acquisition, logging and visualization software Autosoft 3000
  • Specifications   More information…

Fiber Bragg Grating – Optical technology for reliable signal transmission

Over the past 40 years, optical technologies gradually gained more importance in measurement and test engineering. Compared to conventional electrical technologies, fiber optic cables allow for undisturbed signal transmission over large distances.
In the area of classical strain measurement, these advantages can be obtained by using optical strain gauges in the form of Fiber Bragg Grating (FBG). A change in strain of the optical fiber causes a change in the wavelength of the reflected light.

Peekel Instruments now offers a new interrogator for the tried and tested series of measurement devices AUTOLOG 3000 and PICAS-Touch, which can evaluate the optical change in wavelength of the FBG's with a dynamic of up to 15 kHz. The result is converted to a fitting physical unit of measurement, and transferred to the measurement software.

The new interrogator SPK 155 works with a broad-spectrum light source and can evaluate up to 20 FBG's in a fiber optic cable. This technology makes it possible to synchronously measure all sensors with a measurement rate of up to 15 kHz. Through an optical switch, multiple fiber optic cables can be connected to (and measured by) the system.

This novel technology can be applied anywhere where temperatures, strains and vibrations must be measured over long distances, or under difficult electrical conditions. This includes areas like monitoring of large constructions, longtime measurements of structures as well as measurements on high voltage transmission lines and pylons. Fiber optic technology makes it possible to have distances of multiple kilometers between measurement device and the measurement points.

Wave length range45 nm (1525 – 1570 nm)
Number of channels / fibers1, 4, 16
Number of sensors per fiber< 20 1)
Sampling rate per channelup to 15 kHz 2)
Repeatability< 3 pm
Wave length stability< 10 pm
Wave length resolution0,1 pm
Wave length accuracy1 pm
Onboard ProcessingPeak Detection
Bragg Gating FWHMmin. > 0,2 nm; 0,5 nm advised
Mechanical and electrical properties
Temperature0 to 50 °C
Optical connectorFC-APC / LC-APC
Power consumptiontyp. 5 W, max. 10 W
1) Depending on FBG distance: typ. 4 nm distance: about 11 FBG's
2) Depending on number of optical channels: 1: 15 kHz, 4: 5 Hz,16: 1 Hz