Abstract:Electronic weighing instrument compared to the mechanical scale has the advantages of fast, 
intuitive display, not easy to wear and many other advantages, weighing, and its application is more 
and more popular, it has gradually replaced the mechanical scale. In this paper, firstly, the electronic 
weighing instrument structure and expounds principle of weighing, and then discusses the electronic 
weighing instrument and sensor attached circuit repair method.

1 The principle and structure of the electronic scales weighing instrument
The principle of electronic scales is that after loading the weight of the heavy object, the weight signal is transformed from the weighing sensor to the proportional electrical signal output, and then the analog signal of the sensor output is large, filter, A/D Display on the display after conversion and digital processing. The electronic scale is called the heavy instrument can be divided into four parts
First, weighing the sensor part, the main function is to transform the weight signal to the platform into a proportional electrical signal output; the second is to display the instrument part, the main features put the analog signal output of the sensor large, filter, A/D, A/D After conversion, digital processing, display on the display; the third is the scale of the scale, the main function is bearing, the mechanical structure can also be divided into scale, displacement limit, and load -unloading gong embolism; ; Fourth, the external device part refers to the equipment connected to the signal output port connected to the display instrument to receive the instrument output signal; the common external devices include printers, large screen displays, and computer management systems. In addition Solid -state relay output, etc.
Electronic scales can be divided into two categories according to the type of signal source, that is, simulate the weight -bearing meter and numbers. The simulation weighing instrument is received by an analog signal. The scale uses an analog sensor. It is a change to the resistance value of the resistance to the resistance of the resistance to the proportional electrical signal output; the number The weighing instrument is a meter that combines modern electronic technology, micro -processing technology, digital compensation technology and traditional strain -based weighted sensors. It can calculate the weight and display, display, display, display, display, display, display, display, display, and protocols corresponding to the digital sensor. Storage, printing, transmission.
2 Electronic scales Weighing and sensor Affiliated circuit maintenance methods
Electronic scales say that the phenomenon of heavy -duty faults is diverse, and there are many factors that cause failure. And the same failure is often different reasons, because the failure to eliminate the failure, first try to find and confirm the position of the failure, and the finding failure is mainly based on the fault phenomenon and system structure components, components, plug -in, plug -in, and plug -in,, plug -in, plug -in, plug -in, plug -in,, plug -in, plug -ins,,,,, plug -in,,,,,, plug -in, plug -in,,,,, plug -in,,,,,,, case, The role of parts and components, combined with the types of faults summarized when dealing with faults, to check all factors that cause faults, and then use the multi -meter, signal source tool meter, and check the suspicious parts one by one in various ways to finally determine the occurrence of the failure part of the fault. Essence
2.1 Failure caused by the external environment
The changes in the external environment will cause the weight -control photos of the electronic scales mainly include the changes in power supply, vibration, wind, and lightning. Therefore, the electronic scale should try to avoid turning on the wind and thunderstorms, and at the same time, the lightning protection measures and ground protection of the electronic scale should be taken. For vibration, vibration can be taken to reduce its impact. If the power supply power supply is impure, it can be used as a method of wiring or installing parameter regulator for electronic scale.
2.2 Mechanical failure in the scale body
The mechanical failure of the scale body is mainly deformation of the scale body, the scale of the scale is held by the foreign body, the failure of the limit device, and the weighing sensor supports head failure. The frequent upper and lower materials of the electronic scale in the long -term use, constant materials are scattered, and mechanical components have been stagnated and worn for a long time. Whether the body shake is flexibly judged and removes the failure.
2.3 sensor failure
Weighing sensors are key components in the electronic scale, which plays a role in turning gravity into a electrical signal. It is easy to cause a heavy sensor to fail to cause the electronic scale that the weight error, the unable to return to the scale, the large load error, and the variation of the duplication.
1) If the electronic scale weighs the phenomenon of large errors. First of all, we must observe whether the inner code value is stable, whether there is friction in each part of the sensor, whether the voltage power supply is stable, whether the op amp circuit is normal, and test whether the quantity of the four -legged scale of the size of the scale is average. According to the instructions of the instructions, further analysis of the instrument or weight correction.