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Explanations on speci�cations:

Strain Gages and Accessories - 6017 Explanations on speci�cations:

The temperature response involves a tolerance and only applies in the temperaturerange of the temperature response matching. This temperature range is specied in the Specications of the individual series in this catalog. Another possibility of compensating the apparent strain is to use appropriate wiring (e.g. circuit with compensating strain gage, half bridge circuit, etc.).

Creep adjustment

Spring element materials react with a spontaneous positive or negative strain when subjected to a sudden load. In the event of a constant load being applied, the material will continue to strain slowly in load direction, i.e. the material will creep. As transducers are loaded within the strictly elastic range only, the process described here is reversible. It is called elastic after-effect. The elastic after-effect causes a time- dependent fault with a positive sign (in the direction of the deformation by the measu- ring quantity).If a strain gage is subjected to a static load, it will show a slow change in resistanceover time - in spite of the component strain being constant. This change in the measu- ring signal of an extended (or shortened) strain gage occurs in the direction of strain relief. This creep can be explained as follows: the extended measuring grid acts similar to a tensioned spring which generates shear stresses between measuring grid and car- rier (mainly in the area of the measuring grid end loops). Due to the inuence of these stresses, the plastic materials of the strain gage and the adhesive relax. It is possible to inuence such strain gage creep directly by modifying the end loops.De facto therefore, the elastic after-effect of the spring element material will lead to apositive fault while the strain gage creep generates a negative fault. In an ideal case, both faults will compensate each other. In order to approximate this ideal case as clo- sely as possible, it is necessary to determine the most suitable strain gage by experi- ment. It is for this reason, that the K strain gage series provides three different creep adjustments for each strain gage type.

Mechanical hysteresis

The mechanical hysteresis of a strain gage is dened as the difference of the measured value displayed for increasing and decreasing strain loadings with the same strain value on the specimen. Hysteresis is not only dependent on the strain gage but to a major extent it is also dependent on application parameters such as type and layer thickness of the adhesive etc. For this reason, the specications include hysteresisvalues for different installation parameters.

Maximum elongation

The maximum elongation is typically 5 or 50,000 micro-strain. Above this value themeasured strain can not be relied upon. This is often the case if the installation or the strain gage has been damaged. 16Strain Gages and Accessories