A weighing sensor is a precise mechanical induction component. It is prone to various weighing abnormalities under working conditions such as long-term loading, vibration, humidity, electromagnetic interference and improper installation. Most sensor failures are not caused by direct component damage, but by external factors such as zero drift, abnormal force, circuit interference and environmental corrosion. Combining high-frequency faults in industrial sites, this article sorts out a complete fault list, including fault phenomena, causes, inspection steps and solutions. It retains core professional keywords of the industry. The content is easy to understand, suitable for on-site factory operation, and applicable for technical training, equipment maintenance and learning materials.

1. Failure to Return to Zero under No Load (Zero Drift)

Fault Phenomenon: When the equipment is unloaded, the instrument still displays values, fails to return to zero automatically, and frequently has offset base readings.

Causes:

• Large ambient temperature changes cause temperature drift;
• The sensor is damp with aging seals, resulting in decreased insulation of internal circuits;
• Long-term compression produces residual stress on the elastic body and causes creep;
• Oxidized or loose terminals lead to unstable contact resistance;
• Residual impurities and dust on the weighing platform cause continuous slight force.

Solutions: Perform manual zero setting and warm-up calibration; clean foreign matter on the weighing platform; inspect the waterproof structure and replace sensors with IP67 protection rating in humid environments; fasten terminals and polish oxidized contacts; keep the sensor unloaded for a long time to release residual stress.

2. Jittering and Unstable Weighing Data

Fault Phenomenon: The weighing value fluctuates continuously and cannot be locked steadily.

Causes:

• Inverters and motors generate electromagnetic interference;
• Damaged shielding layer makes signal cables susceptible to external wave interference;
• Severe equipment vibration and unfixed weighing platform cause continuous shaking;
• Unbalanced force distribution in multi-sensor combination leads to repeated stress changes.

Solutions: Arrange signal cables separately away from high-power equipment; replace shielded cables with reliable grounding; install shock-absorbing pads and limit devices; level the weighing platform to ensure uniform force; activate the instrument filtering function to reduce data fluctuation.

3. Inaccurate Weighing and Poor Repeatability

Fault Phenomenon: The same weight shows obvious deviation in repeated measurements; the weighing value is consistently higher or lower with excessive errors.

Causes:

• Slight overload causes elastic body fatigue and increases linear error;
• Inclined installation leads to lateral shear force;
• Stuck weighing modules and rusty bases generate excessive friction;
• Incorrectly modified instrument parameters cause calibration coefficient disorder.

Solutions: Recalibrate with standard weights; clean rust and foreign matter to keep contact surfaces smooth; level the sensor to avoid lateral force; restore factory parameters and lock modification permissions; directly replace severely aging sensors with poor repeatability.

4. No Signal and Weighing Failure

Fault Phenomenon: The instrument displays no signal or disconnection alarm with blank weighing data.

Causes:

• Cable breakage and water ingress through damaged sheaths;
• Short circuit or reversed positive and negative wiring;
• Unstable voltage causes breakdown of internal strain gauges;
• Long-term corrosion completely damages internal circuits.

Solutions: Measure resistance with a multimeter to check circuit continuity; standardize wiring and distinguish power, signal and ground wires; replace damaged cables and waterproof joints; install voltage stabilizers for fluctuating voltage conditions; directly replace irreparable burnt or broken sensors.

5. No Response under Load and Fixed Weight Readings

Fault Phenomenon: The reading remains unchanged whether loaded or unloaded.

Causes: Over-tight limit devices jam the weighing platform; the sensor is stuck and cannot deform; internal strain gauges are disconnected; the instrument acquisition program freezes.

Solutions: Loosen limit gaps to reserve deformation allowance; disassemble and inspect sensor deformation; restart the instrument; replace sensors with damaged strain gauges (non-repairable).

6. Large Errors Caused by Temperature Changes (Severe Temperature Drift)

Fault Phenomenon: Obvious weighing deviation occurs under large temperature differences while readings are normal at room temperature.

Causes: Ordinary sensors lack temperature compensation; ambient temperature exceeds the working range; water ingress aggravates internal resistance deviation.

Solutions: Adopt temperature-compensated industrial sensors for extreme temperature environments; conduct regular temperature calibration in winter and summer; strengthen waterproof sealing to prevent water vapor intrusion.

7. Sensor Aging and Long-term Accuracy Attenuation

Fault Phenomenon: Accuracy decreases year by year after long-term use, and deviation recurs shortly after calibration.

Causes: Frequent impact load and long-term full-load operation; oxidation and rust of alloy steel; irreversible accumulated creep.

Solutions: Reserve sufficient safety overload margin; use stainless steel sensors in humid environments; perform quarterly calibration; replace severely aging sensors instead of repeated use.

8. General Maintenance & Prevention Tips

To reduce failure rate and extend service life, the following maintenance principles must be followed in industrial applications:

• No Overloading: The maximum load shall not exceed 80% of the rated range;
• Anti-lateral Force: Avoid torsion, shear force and transverse impact;
• Water and Dust Resistance: Adopt IP67 or higher protection grade in humid environments;
• Regular Calibration: Calibrate industrial scales at least once a month;
• Interference Isolation: Ground shielded signal cables and keep away from inverters and welding machines.

9. Summary

More than 90% of weighing sensor faults are not caused by product quality defects, but by improper installation, harsh environment, non-standard operation and insufficient maintenance. The four most common faults arezero drift, data jitter, poor repeatability and circuit failure. Daily maintenance should focus on moisture prevention, electromagnetic shielding, lateral force prevention and overload prohibition. Mastering fault diagnosis methods can realize rapid inspection and repair, reduce equipment downtime costs, and ensure long-term stable and accurate operation of industrial weighing systems.