From the perspective of the coating thickness detector itself, aging of core components and lack of calibration are the main sources of error. The sensor of the detector, as the core component, may experience a decrease in signal reception and transmission accuracy due to wear, oxidation, and other issues after long-term use. For example, if the probe of a magnetic induction detector has magnetic core loss, it will cause the detection data to deviate from the actual value. At the same time, if the instrument is not calibrated according to the prescribed cycle, or if calibration blocks that do not meet the standards are used, the measurement benchmark of the instrument will gradually shift, resulting in errors. In this regard, enterprises should establish a sound instrument maintenance system, regularly check the status of sensors, and replace them in a timely manner once signs of aging are found; At the same time, strictly follow the equipment manual requirements and use standard test blocks for calibration every 3-6 months to ensure that the instrument is always in a precise state.

The non-standard operation process can also cause significant errors. On the one hand, if the operator does not master the correct detection technique, such as improper contact angle between the probe and the surface of the tested workpiece (ideal angle is 90 ° perpendicular), uneven pressure application, it can lead to unstable detection signals. Taking the eddy current coating thickness gauge as an example, when the probe is tilted, the distribution of the eddy current field changes, and the measurement results may have a deviation of ± 5% or more. On the other hand, if the surface of the workpiece is not pre treated before detection, residual oil stains, oxide layers, or impurities can hinder signal transmission and affect detection accuracy. To address this issue, enterprises need to strengthen the training of operators and ensure their proficiency in correct detection posture and pressure control skills through practical assessments; At the same time, before testing, use alcohol wiping, sandpaper lightly grinding and other methods to clean the surface of the workpiece and eliminate interference factors.

Environmental factors cannot be ignored either. The drastic changes in temperature and humidity can affect the working state of electronic components inside the instrument. For example, high temperatures can cause an increase in circuit resistance and weaken detection signals; A humid environment may cause internal short circuits in the instrument, resulting in abnormal data. In addition, strong magnetic fields in the surrounding environment (such as near large motors and transformers) can interfere with the magnetic field of magnetic induction detectors, leading to measurement errors. To solve environmental problems, enterprises should control the temperature of the testing area at 20-25 ℃, maintain humidity at 40% -60%, and stay away from strong magnetic field equipment; If the detection environment is difficult to control, the detector can be equipped with a constant temperature and humidity chamber or a magnetic shielding device to reduce the impact of the environment on the detection accuracy.