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Peakanalyzer Installation Manual Version 2.6
2.7
Application of strain gauges
Strain gauges are for the measurement of the stretching of a material surface. They change
their electrical resistance proportional to the stretching of the surface.
The Baseanalyzer has the functionality to measure and analyze the movement and stretching
of the basement of a wind energy turbine in vertical direction. For this a strain gauge is applied
to the basement section and connected to the Baseanalyzer. Also see chapter 2.3.11.
Below is a short description of the application of a strain gauge. If a strain gauge is included in
the supply, a detailed step by step description for the handling of the glue and covering material
can be found in the package.
The applicable full bridge in Picture 26 consists of two double strain gauges (T-Rosette). It
requires two additional electrical connections between the resistors 1 and 4 as well as 2 and
3 in the form of a steel wire bridge.
Picture 26: Arrangement of a strain gauge to measure the normal strain on one layer
Description of a strain gauge application:
1. Extensive cleaning of the application surface (brake cleaner, alcohol)
2. Removal of color in the range of the strain gauge 3x6 cm
3. Gluing the strain gauge according to description
4. Solder the steel wire bridges between the resistor 1 and 4 as well as 2 and 3 (steel wire,
soldering iron, tin solder, flux)
5. Connect measure cables (soldering iron, tin solder, flux)
6. Test functionality, Ud < 25 mV
7. Clean the measurement object and cover it according to the detailed description (the last
layer is the aluminum foil)
The cleaning of the measuring point also includes the removal of flux with Rosin Solvent or
alcohol (Isopropyl alcohol 70%). The careful application according to the description by
avoidance of any pollution and a careful covering of the strain gauge is very important for a
reliable functionality of the strain gauge.