The circuit failure of the concrete batching machine
is manifested as the value of the controller overflows, the error message is displayed, and the signal is suddenly interrupted or jumped randomly during weighing. The reasons are as follows.
One is that the connection line between the sensor of the concrete batching machine
and the control instrument is broken. This kind of external fault is mainly caused by improper installation and use. If you use a multimeter to check the sensor input and output resistance, the resistance values are normal. The reasons for the failure are: the connecting wire is broken, causing an open circuit; the connecting wire joint is loose or not soldered solidly, etc.
The second is the quality of the sensor of the concrete batching machine
itself. It shows that the sensor input and output resistance change. Under normal conditions, the input resistance of the sensor is 400Ω±10Ω, and the output resistance is 350Ω±3Ω. The main fault of the sensor is that the solder joints of the terminal or lead wire fall off; the sensor zero temperature compensation or sensitivity temperature compensation resistance is soldered or unsoldered; the sensor is not well sealed and the internal chip is damp.
An abnormal zero point of an electronic scale is also a common fault. One of the reasons is that the sensor is not temperature compensated. The zero point and sensitivity of the sensor change with the change of the ambient temperature, which causes the zero point of the electronic scale to malfunction. According to the international standard sensor production process has a temperature compensation process, the sensor should be simulated through a high and low temperature box. The ambient temperature changes are used to compensate, but many domestic sensor manufacturers do not have high and low temperature boxes at all and cannot compensate the temperature of the sensor; the second reason is that the sensor is seriously overloaded, which causes plastic deformation of the elastic body and damages the sensor.
In addition, water in the junction box, moisture, oxidation, or resistance breakdown may cause major failures.