MTS Clip-On Gages - Manual (Page 18)

Introduction 18
About Wheatstone Bridge
The axial transducer uses precision, resistance-type, foil strain gages
bonded to a metallic element to form a Wheatstone bridge. Two knife
edges on the transducer arms contact the specimen. Elongation or
compression of the specimen causes movement of the transducer arms.
This movement bends the metallic element, changing the resistance of
the strain gages. The change in the balance of the Wheatstone bridge
produces an electrical output that is proportional to the displacement of
the transducer arms.
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Sensor
Bridge