MTS Axial Extensometers - Manual (Page 17)

Introduction 17
Axial Extensometer Functional Description
An axial extensometer is a sensor attached to a specimen that measures
a dimensional change (gage length or strain) that occurs in the specimen
while being tested. Extensometers use a Wheatstone bridge circuit to
detect the dimensional changes. Because they are DC devices, they
require a DC conditioner for signal processing. The following
paragraphs describe the functions of the axial extensometers.
About DC Conditioning
The transducer requires a DC conditioner to process the transducer
signal. A DC conditioner provides a DC excitation voltage to the
transducer. Any changes to the gage length of the transducer change the
excitation signal. The changed signal is output to the DC conditioner as
feedback. The DC conditioner processes the signal and makes it
available to the controller where the signal may be used.
Typical Conditioning Circuit
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