What is the cause of zero instability in electronic scales? How to solve it?
1. Analysis of zero instability of electronic scales
1.1 The weighing material is not strong. During the use, the table top is in direct contact with the items to be weighed, so when weighing. Whether the electronic scale is empty or full load needs to be on the same level, otherwise there will be some error in weighing. In the material selection of the electronic scale countertop, we should try to use some weighing bodies with better strength, strong rigidity and not easy to deform.
1.2 Sensor failure As an electronic instrument, the accuracy of the electronic scale is very high, so there are often some faults. The sensor is a very prone to fault location in the electronic scale. Especially when the voltage signal of the zero point signal output is too high or too low at no load, this situation will cause the zero point of the electronic scale to be undisplayable.
1.3 The voltage signal output of the sensor zero point is too high or too low. According to the practice of repairing the sensor, we can find out. In the event of a sensor failure, the scale will not display the zero point properly. Most of the cases are caused by the zero-voltage output being too high, and according to the statistics of some data, all the faults that cause the electronic scale zero display to be unstable, because the sensor zero-point voltage output is too high, the fault occurs, which is a large proportion. The principle of the bridge measuring circuit is analyzed at about 80%. To make the circuit signal linear in the output process. The four resistors on the sensor should have the adjacent two strain gauges in a complementary shape. When the zero-point voltage of the sensor is excessively high, the elastic body is deformed, so that the corresponding resistance value becomes larger or smaller, resulting in an increase in the potential of the output signal of the sensor.
If the voltage output from the sensor is too low, it will cause the elastomer to deform. The strain gauges which are reversely changed are compressed to some extent. The resistance of the strain gauge is reduced or we can lengthen the positively varying strain gauge. Increase its resistance. At this time, the positive signal potential of the sensor output will gradually decrease. The voltage signal output of the sensor zero is too low. The fault is similar to the case where the voltage output is too high. If the voltage output from the sensor is too low, the elastomer will be deformed. The resistance strain gauge that changes in the opposite direction will be compressed to some extent. The resistance of the strain gauge is reduced or we can lengthen the positively-changing strain gauge. Increase the resistance. At this time, the positive signal potential of the sensor will gradually decrease the voltage output of the sensor zero. The situation in which an output too high fault occurs is similar.
2. Solutions for the above faults
If the sensor that replaces the scale has a problem with the sensor of the scale, we can take some pressure to apply it or lift the scale up to make the zero value display properly or replace the sensor directly. But replacing the sensor is a very complicated task. Taking the method of repairing the sensor not only saves time but also saves a part of the money. Therefore, in daily life, people are more willing to choose the method of repairing the sensor. Due to the increasing demand for electronic scales, there are more and more solutions to the failure of sensors. The simplest and most effective way is to replace the resistors on the board.
When the sensor is shipped from the factory, its measuring bridge is in an equilibrium position, so the output voltage of the measuring bridge should be zero without any load. The frequent use of electronic scales or the pressure of some objects. Even excessive pressure loads cause deformation of the sensor. In severe cases, the electronic components in the sensor are directly affected, which makes the measurement bridge unbalanced, which directly causes the signal of the zero-point voltage output to be in an unbalanced state. Make the electronic scale not display the zero point normally. A serious situation will directly cause zero to be displayed.