Extensometer calibrators are used either where an extensometer does not feature electrical calibration or when a manual verification of the output is desired.
The calibrator consists of a precision micrometer head that drives a separate moveable shaft. The micrometer head and shaft are mounted on a frame and the extensometer is attached between the moving and stationary shafts.
Displacement is shown via a digital display.
Principle of Operation
The extensometer is clipped to interchangeable adaptors that simulate different specimen sizes. One half of the adaptor is adjustable, while the other remains stationary. As the micrometer is adjusted, the upper adaptor moves and displacement is applied to the extensometer.
The elongation is read from the digital display of the micrometer head. This can be used to either verify the output of the extensometer shown on the test system or to set zero and full scale output to calibrate it initially.