The weighing accuracy of the weighing sensor is directly affected when the internal resistance element is damaged due to corrosion and moisture as the core electronic component of the weighing device. So how should we determine whether the sensor is damaged? Zhengxing weighing instrument brings the following five judgment methods!

1. Appearance inspection: carefully check the appearance of the inspected sensor. If the appearance is damaged and cracked, it indicates that the weighing sensor of the truck scale may be damaged.

2. Rough line inspection: the power supply line, signal line and shield wire of the sensor are coaxial cables, which can be measured with a multimeter (i.e. power line - signal line, power line - shield wire, signal line - shield wire). If there is a short circuit, broken wire or insulation degradation, it indicates that the sensor may be damaged.

3. Measurement of internal resistance: in the absence of special testing equipment, the input impedance ZI and output impedance ZO of the truck scale load cell can be measured with the ohm gear of a digital multimeter, and the measured value is compared with the nominal value on the product certificate provided by the manufacturer. If the measured value exceeds the allowable range, it indicates that the sensor may be damaged.

4. No-load detection:

(1) Remove all sensors and connect them to the measuring circuit one by one. Under the condition of no external load (no load), the sensor with good performance will quickly return to zero and the displayed value is relatively stable, while the damaged sensor may have a jump in the displayed value and cannot return to zero. The above phenomenon will still occur after manual reset.

(2) Connect all the load cells, and still carry out no-load measurement. When measuring, first remove one sensor and observe whether the displayed value can be stable. Then connect the sensor again, then remove the other sensor and measure it. Measure all the sensors in sequence. If a sensor is removed and the displayed value returns to normal, it indicates that the sensor may be damaged.

5. Load verification: When the damaged load cells cannot be determined by using the above methods, the standard metering calibration method can be used to verify the load of all sensors. The method is to load the sensors one by one with a standard weight of 1t. The measured value displayed by the undamaged sensor should be the superimposed value of the standard weight after gradual loading, while the measured value displayed by the damaged load cell will have a large deviation from the superimposed value of the standard weight after gradual loading (generally, the loading amount should be greater than 20% of the rated load of the sensor).