Caleb Tidball, Cardinal Scale, USA, discusses whether analogue or digital trucks scales should be used in coal mining production.
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oal mining is a critical part of meeting the world’s energy demands. The coal industry requires a great deal from its truck scales: accuracy, longevity, and the ability to operate consistently for long periods of time without breaking down. Meeting increasing energy demands requires high performance from equipment used to weigh coal. Therefore, researching the variations of truck scale types and their respective attributes is an important process, and the differrent advantages of analogue and digital truck scale systems should be considered.
Analogue truck scales Analogue truck scales are the most common type of truck scale available on the market. This type of truck scale combines electrical signals from
individual analogue strain gauge load cells and sums them in a junction box. These combined signals are then fed from the junction box into an indicator and converted into a digital value displayed for the customer to view. Analogue load cells come in many variations, but the two most common types used in truck scales are the compression load cell and the shear beam load cell. A truck scale system employing analogue load cells has some distinct advantages. Analogue load cells are inexpensive, have been on the market for a relatively long period, and have a fairly wide range of weight capacities. However, analogue load cells have many drawbacks. Because of their construction and electrical characteristics, they are especially sensitive to lightning damage. When a 70 ft long piece of
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