Imagine a situation where a large consignment of parts has been received in a factory, and the parts are very small and their number is large and they have to be paid for. Unfortunately, their supplier has quoted their rate per individual part, and therefore they have to be counted before payment is made.
For counting them a sizeable team of workers would be required. So, either some of the workers shall have to be withdrawn from other jobs or some new workers would have to be recruited for a short time. It will need time as well as money. However, there is a way out. Precise counting scales for small parts are available which can do the job easily in a short time.
These scales are weighing scales that have been adapted for counting. The whole lot of items to be counted is put on the counting scale, and a single part is separately weighed on a scale and its weight is fed into the counting scale. The counting scale weighs the lot and arrives at the number of parts by dividing the total weight of the lot by the weight of a single part. The number is displayed on the scale.
However, there are some requirements of a weighing scale that has to be used for counting. It should be capable of weighing heavy loads and at the same time be sensitive to very small changes in weight. Even if a single part is removed or put on the scale, the scale should respond to that, otherwise, there would be an error in counting. It should also be very accurate.