Contents
What is the point of a Wheatstone bridge?
A Wheatstone bridge is an electrical circuit used to measure an unknown electrical resistance by balancing two legs of a bridge circuit, one leg of which includes the unknown component.
Why do we need strain gauges?
It’s primary use is to measure force or strain. The resistance of a strain gauge changes when force is applied and this change will give a different electrical output. Strain gauges use this method to measure pressure, force, weight and tension.
How does the Wheatstone bridge for strain gauges work?
A Wheatstone bridge is a divided bridge circuit used for the measurement of static or dynamic electrical resistance. The output voltage of the Wheatstone bridge circuit is expressed in millivolts output per volt input. The Wheatstone circuit is also well suited for temperature compensation.
How does cable resistance affect Wheatstone bridge circuit?
If temperature-dependent strain occurs, the strain appears to both strain gauges with the same sign. Thus the effects cancel each other out in the Wheatstone bridge circuit. The effect of cable resistance can be largely compensated for selectively by a three wire circuit.
What can the Wheatstone bridge be used for?
The Wheatstone bridge can be used in various ways to measure electrical resistance: The latter method is used with regard to strain gauge techniques. It enables relative changes of resistance in the strain gauge, which are usually around the order of 10 -4 to 10 -2 Ω/Ω to be measured with great accuracy.
How is the configuration of a strain gauge used?
The Wheatstone bridge configuration is used to help measure the small variations in resistance that the sensing elements produce corresponding to a physical change in the specimen. Strain-gauge configurations are arranged as Wheatstone bridges. The gauge is the collection of all of the active elements of the Wheatstone bridge.