With the increase of China's national strength, the frequency of bulk cargo transportation is also getting higher and higher, so the scope and frequency of the weighbridge equipment are greatly increased. However, in the actual verification work, the accuracy of the weighbridge is often affected by some factors. Therefore, in this paper, the author will discuss the problems of the scales in the scale verification work and the solutions based on the actual work experience and reference materials.

Common problems in verification work and solutions

The meter display is unstable. When the weighbridge is inspected, its instrument display often shows instability. The meter displays the number fluctuating between 1kg and 1000kg. This happens, mostly because the scale meter shows damage in the internal analog part, and power failure, sensor and cable failures can also cause the instrument signal to change. In addition, when there is no gap between the foundation and the limit bolt, and the occurrence of debris between the base and the weighing platform, it will also cause changes in the instrument signal.

Countermeasure: The instrument display is unstable when the scale is checked. The first step is to clean the debris around the weighing platform and check whether the limit device is installed correctly. Secondly, check the line of the meter to determine whether the line appears and The connector is loose; finally, the junction box and the sensor are inspected to determine if they are working properly.

Weighing error. When the weighbridge is inspected, because the accuracy of the meter adjustment is reduced and the analog part of the instrument is destroyed, the foundation of the platform will be problematic. Coupled with the instability of sensors, junction boxes and angular differences, it will make The weighing error of the metrological verification work becomes larger. In addition, when the platform is inspected, one of the most important tasks is the eccentric load debugging. If the eccentric load debugging is out of tolerance, it will have a serious impact on the weighing work and an imbalance will occur.

Countermeasure: Weighing error is a very common error when the weighbridge is tested. The definition of it is generally required by the verification personnel to use the weight for calibration. First, check the instrument sensor and the junction box to determine whether it can work normally. Secondly, adjust the angular difference and adjust it through the junction box. Finally, if the weighing error occurs, you need to The weighing platform is adjusted. When adjusting, the resistance of the junction box is leveled by a multimeter, and then the weight difference is finely adjusted by the weight. The eccentricity of the verification of the weighbridge requires adjustment of the potentiometer on the junction board in the junction box.

Unrelated errors increase the weighing error. When performing the verification work, it is necessary to operate according to the relevant regulations. In the regulation requirements, five test points are required in the process of the scale verification, but it cannot be completed during the actual operation. Moreover, in the verification process, due to the influence of factors such as limit and shielding, it needs to be adjusted repeatedly. In this process, it requires a lot of manpower and material resources, so the error will inevitably occur.

Countermeasure: To solve the influence of the irrelevant error symmetry error of the verification link, it can be considered from two aspects. First, if the error is within the allowable range, then its impact on the verification work is ignored; secondly, The irrelevant error affecting the verification result, for this part of the error within the scope of the scientific measurement principle, to minimize or avoid the occurrence of error, to ensure the quality of the verification work.

Weighbridge use advice

Prepare before use. First of all, the installation needs to be installed before the use of the weighbridge. After installation, the instructions of the instrument and the installation drawings and certificates are properly kept, and then applied to the relevant metrology department or the quality department approved by the state. After the inspection by the relevant departments, Officially put into use. Secondly, before the power system is powered on, the power supply of the system power supply should be checked to determine whether the grounding device is reliable, and the system power supply should be cut off after the work is completed to ensure the safety of the system. Finally, before use, the controller should be pre-heated symmetrically. The preheating time of the machine usually lasts for about half an hour. During the preheating, the flexible performance and operation status of each part of the scale body should be checked to ensure that it is not Will affect the measurement work.

Preventive work in use. First of all, in order to ensure accurate measurement results of the weighbridge system, lightning protection facilities should be installed during use, and when the welding work is carried out near the scale, the weighing platform cannot be used as the neutral grounding terminal to avoid damage to the electrical components of the system. At the same time, some ground balances used in field operations must be regularly inspected for their drainage devices to avoid clogging and affect normal use. Secondly, during use, make sure that the weighbridge junction box is kept dry. Once there is moisture in the junction box, it should be dried immediately. At the same time, in order to ensure the accurate measurement results of the instrument, the instrument should be periodically calibrated and calibrated. Finally, when measuring heavy objects, the impact phenomenon cannot occur, and the weight of the measuring object must be within the rated weighing range of the system. In addition, in order to ensure accurate measurement results in the automotive industry, it is generally not allowed to overbalance the short-wheelbase vehicles such as forklifts.

Maintenance after use. Whether in the use of the weighbridge or after use, professional users and maintenance personnel are required to operate and maintain the platform. The operating staff of the scales must have a solid understanding of the use of the weighbridge and the relevant technical know-how to ensure that there are no safety accidents and accidental operations during the use, to ensure the accuracy of the measurement results and the smooth progress of the measurement work. Maintenance and protection personnel must not only have sufficient mastery of the use of the weighbridge, but also have a deep understanding of the maintenance and protection process and technical means of the automobile dealers. Relevant staff members must be professionally trained and have relevant technical documents before they can be employed. jobs. In addition, both the SPE operator and the maintenance and protection personnel must have a solid technical foundation so that the work of the Weighbridge can be carried out in an orderly manner without affecting the progress of the work.

Careful analysis of the problems in the verification work of the weighbridge and the proposed countermeasures can significantly improve the accuracy of the metrological verification work. In the future weighbridge verification work, the verification method should be improved in time to promote the scientific and healthy development of the scale test.