The Unit for Determining the Gauge Factor of Strain Gauges, ,MFGE,, allows to determine the k factor of strain gauges.
The bar rests on two supports with ball bearings, so that it is possible to work with a load under pure bending.
To perform such determination two point loads must be applied to the bar, with the load application handwheel, connected to a cross-arm, through a spindle that, when rotating the handwheel, leads to the application of a force in two points of the bar with vertical direction downwards. This force causes a deformation on the bar.
There is a dial gauge, to measure the deformation generated. The dial gauge measures the maximum deformation, which is given in the center of the bar.
At the same time, the deformation generated on the surface of the bar is registered by two strain gauges in the compression side and other two strain gauges in the tension side, forming a full Wheatstone bridge. The strain value, expressed in volts, will be read in a console that amplifies the signal of the strain gauges.
The gauge factor (k) can be calculated from the displacement values obtained and the strain gauges measurements.