Training Stuff

Self-Elastic Modulus Compensation Strain Gages

release date:2017-02-07 23:53:21


Introduction:
With rising of the ambient temperature, the elastic modulus materials will go down. According to the theory of Hooke, as environmental temperature increases the deformation of this structure will be bigger even if the load is not changed. Therefore, the tested strain will be increased along with it. At that time, if the gage factor can be reduced properly with temperature, the output of gages will not be changed as temperature changes. Therefore, the compensation of elastic modulus will be realized. This kind of strain gages is also called self-elastic modulus compensation strain gages.
The self-elastic modulus compensation strain gages perform the function of common gages and elastic modulus compensation resistor. It can also provide good correction of the sensitivity error of transducer that is caused by material of elastic modulus changes with temperature. If self-elastic modulus compensation strain gages are matched well spring materials, the temperature drift of transducer sensitivity will be less than 0.002%FS/℃ . Compared to common used methods, the selfelastic modulus compensation strain gages take the advantages of high accuracy in compensation, good stability, higher sensitivity, easier usage, lower cost and so on. However, the thermal output of strain gages only with self-elastic modulus compensation is a little bit larger, so zero temperature drift of transducers will be larger, which limits to further improve the precision of transducers. After many years research, we have developed and produced strain gages with self-temperature compensation and self-elastic modulus compensation that solve these problems. Especially for strain gages with half and full bridge. They have become very popular because of their good temperature capability.

Notes for using EMC gages:

(1) In order to get satisfied compensation result, the elastic modulus compensation gages must be matched transducer spring materials. Generally, we should choose proper strain gages by testing at least five transducers.
(2)The gages have no functions of self-temperature compensation for most materials; their thermal output is larger than those of ordinary self-temperature compensation gages, therefore they are recommended to use for transducers with smaller temperature grads. It is better to adopt half-bridge or full-bridge gages to gain less zero-temperature drift.
(3)Soldering of elastic modulus compensation gages is more difficult than those of common gages. A special flux can be available from our factory. Carefully solder and clean them completely.