1、 Display abnormal faults

1. Data instability/jump
   • phenomenonThe displayed value fluctuates frequently when unloaded or weighed.
   • reasonLoose wiring, damaged signal lines, strong electromagnetic interference (such as frequency converters, high-power motors), poor system grounding, mechanical vibration, or moisture inside sensors.
   • solveTighten the wiring terminals, replace damaged cables, use shielded cables and single point grounding, keep away from interference sources, and check the sealing of the sensor.
2. zero drift
   • phenomenonMinor errors are displayed when not under force, or the values continue to shift after preheating.
   • reasonSensor overload damage, scale body stuck by foreign objects, unstable installation foundation, improper adjustment of limit device, uneven force distribution among multiple sensors.
   • solveCheck if the sensor is overloaded, remove foreign objects, reinforce the foundation, adjust the limit gap (leaving 2-5mm), and ensure that multiple sensors are evenly stressed.
3. No display after loading
   • phenomenonAfter applying the load, the instrument shows no response or the reading is significantly lower.
   • reasonThe sensor is severely damaged, the signal line is broken, the wiring inside the junction box is faulty, and the instrument input channel is damaged.
   • solveUse a multimeter to measure the input/output resistance of the sensor, check the integrity of the signal line, and replace damaged components.

2、 Output signal fault

1. Abnormal output signal
   • phenomenonWhen unloaded, the output voltage deviates from the normal range (such as beyond ± 0.2mV/V), or when fully loaded, the sensitivity decreases.
   • reasonDamage to the Wheatstone bridge inside the sensor, virtual soldering of solder joints, and aging of strain gauges.
   • solveMeasure the voltage at the signal output terminal, calculate the mV/V value, and replace the sensor if it is abnormal.
2. Insulation resistance decreases
   • phenomenonThe resistance between the sensor housing and the signal line is less than 5000M Ω.
   • reasonPoor sealing leads to moisture, water ingress into internal circuits, and contact between solder joints on the wiring board and the shell.
   • solveDry the junction box, replace the sealing ring, inspect and clean the oxidized solder joints.

3、 Mechanical structural faults

1. Mechanical hysteresis exceeds the tolerance
   • phenomenonThe results of weighing the same load multiple times are inconsistent and have poor repeatability.
   • reasonPoor characteristics of resistance strain gauges, defects in elastic material or geometric shape, and deterioration of adhesives.
   • solveCheck the quality of strain gauge adhesion and replace the elastomer or sensor.
2. Not returning to zero or not returning to zero after loading
   • phenomenonAfter removing the load, the zero point offset cannot be restored.
   • reasonImproper heat treatment of elastomeric materials, defects in strain gauge bonding and curing processes, and insufficient sealing measures.
   • solveRe calibrate the zero point, check the quality of the elastomer, and strengthen the sealing treatment.

4、 Environmental and operational faults

1. Poor environmental adaptability
   • phenomenonPerformance degradation or frequent malfunctions in high temperature and humid environments.
   • reasonThe protection level of the sensor is insufficient, and the internal components are aging.
   • solveSelect sensors with a protection level of ≥ IP65 to optimize the working environment.
2. Improper operation leading to malfunction
   • phenomenonSensor overload, impact damage, or installation tilt.
   • reasonOver range use, direct impact of heavy objects on the weighing platform, installation not leveled.
   • solveStrictly use according to the measuring range, avoid impact, and ensure that the sensor is installed horizontally.