With the rapid development of the economy, the original business mode of small stalls and hawkers has changed to farmers' markets and supermarkets, and the original workshops have become large-scale industrial centralized production. Industrial and agricultural production use a large number of measuring instruments, especially electronic scales. Standardized production is based on measurement. For example, the measurement of industries such as food, medicine, metallurgy, and chemical industry requires that the formula quantity must not be wrong so that the product quality can be controlled. The inventory of warehouses and yards, and the transportation and distribution of traffic also need electronic scales to control. From the survey of large wholesale markets, it was found that aquatic products, agricultural trade, vegetable and meat markets have a large number of electronic scales and are difficult to manage. Once the scales are cheated and inaccurate, they cannot be supervised in real time, and the unfairness of transactions makes the market order unguaranteed. It is difficult for the measurement department and the regulatory department to implement services and management in place, and the measurement and regulatory services seem to be stretched. For this reason, how can we find the inaccurate electronic scales in a timely and accurate manner among the hundreds of electronic scales in each market? This is a top priority. We must always ensure the fairness, safety and stability of the market and industrial product quality. We need to use digitalization and Internet of Things technology to accurately and timely capture inaccurate electronic scales.
1  Phenomenon and causes of inaccurate electronic scales in places where electronic scales are used on a large scale. In places where electronic scales are used on a large scale (taking farmers' markets as an example below), from the data of calibration, the calibration pass rate of hundreds of electronic scales in farmers' markets, especially some large seafood wholesale markets, is less than 50%. The reasons for their inaccuracy are as follows:
(1) The electronic scale itself causes inaccuracy. Cheap materials, such as steel that is cut corners and lacks torsion resistance; insufficient moisture resistance of circuit boards; insufficient sealing of the outer shell causes insects and ants to invade circuit boards and lines; poor quality of sensor sealant causes impedance to change over time, causing the value to change accordingly.
(2) Inaccuracy caused by natural factors such as collision and electric shock.
(3) Inaccuracy caused by cheating of electronic scales. Especially in places where electronic scales are used on a large scale, driven by profit, unscrupulous merchants use methods of transformation and destructive change of data, and use technical means to increase or decrease the original data (i.e. the measured value) according to their needs, which is what we often call cheating. There are many cheating methods, some of which increase or decrease the voltage on the power line of the sensor, some of which adjust the impedance at the input end of the sensor line, and some of which are processed on the chip at the receiving end of the instrument, etc. Of course, this basically exists in analog electronic scales.
(4) Improper use of electronic scales causes inaccuracy. For example, the scale platform is not level; there is a soft blockage between the scale table and the scale body; rough movement, etc. will cause line damage, affecting the accuracy of the measured value.
(5) The use environment of the electronic scale is subject to strong electromagnetic interference and electric shock, causing disorder of the chip program.
(6) Criminals copy the multiplier program into the instrument chip of the electronic scale for technical manipulation.