Strain Gauge - The Delicate Performer In A Digital Scale

By Author: Steve Swall
Total Articles: 9
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When you see a large digital scale that can weigh very very large objects which weigh thousands of kilograms you will expect that the scale is designed to be very tough and rugged so that it can withstand being subjected to such a lot of stress. Which of course is true. After all when the object is placed on it, it is by measuring the strain caused by the stress that the digital scale is able to inform you the weight of the object.

And so for example, you would perhaps expect the components inside a digital floor scale specially the mechanical ones which are not an electronic component to be all heavy duty able and waiting to endure the stress of a lot of weight being placed on them. But you will find inside a floor scale there are a few number of components that are very delicate and sensitive. And this is so by design because their sensitivity enables them to measure the strain. And these are the strain gauges.

So how does a strain gauge the strain. First let me tell you what strain is in this context. When the load cell's metal component experiences stress it changes shape. This change in shape in lay man's ...
... language is the strain caused by the stress. It is a bending type of change in shape. The strain gauge is fixed on to the metal component with the help of a quality suitable adhesive. Hence when the metal component bends so does the strain gauge. And depending on how much it has bent the resistance offered by the strain gauge when placed in an electric circuit changes. This change in resistance is measured and that directly relates to the weight of the object placed on the scale.

To be able to do this the strain gauge is a long delicate thin wire that is placed in a small area. When it gets deformed the resistance it offers changes proportionately. Quality strain gauges require quality manufacturing facilities. You can know more about the latest digital scales such as floor scale at http://www.scribd.com/doc/111890260/Floor-Scale-Choose-the-Platform-Size-Well.