1 external factors

The commercial concrete mixing station for hydropower station construction is installed at the construction site. The on-site use environment is harsh. Many factors such as ambient temperature, humidity, atmospheric pressure, vibration, magnetic field and electric field may introduce the change of the error, the zero drift and the sensitivity change. In the process of use, sensor structure, capacity, technical parameter selection, material given, and unreasonable installation process will also cause errors in the measurement results and even increase the damage rate of the sensor. Therefore, the manufacturing verification index of the load cell cannot be equal to the accuracy of the actual performance and other performance indicators. Although sensor manufacturing technology is constantly improving, the use of load cells must not be neglected. When conditions of use change, measures must be taken to limit various sources of error.

2 intrinsic factors

Compressed strain gauges are commonly used in commercial concrete mixing plant load cells. The working principle is based on the elastic deformation of elastic bodies (elastic elements) under external force, so that the strain gauges (conversion elements) attached to the surface are also deformed at the same time. Therefore, the resistance value of the strain gauge is changed (increased or decreased), and then the corresponding measurement circuit converts the change of the resistance into an electrical signal (voltage or current), and outputs an electrical signal proportional to the weight, thereby realizing the measurement. The purpose of weight. Therefore, the manufacturing process quality of elastomers, strain gauges, strain gauges and measuring circuits is the key to the accuracy of the load cell measurement.

The elastomer is a structural member with a special shape. Its function is two, first of all, it bears the external force of the load cell, and secondly, it produces a high-quality strain zone, so that the resistance strain stuck in this zone completes the signal conversion task. Therefore, it can be said that the metal material of the elastomer, the forging, machining, heat treatment and surface treatment of the metal material are supporting processes for ensuring the measurement accuracy of the load cell, which determine the hardenability, strength and toughness, fatigue strength of the elastomer. Wait. The resistance strain gauge is the core component of the load cell. Its working principle is based on the resistance strain effect of the material and is adhered to the sensor elastic component with an adhesive. Its own manufacturing process, strain gauge adhesive (strain adhesive) is the basic process to ensure the measurement accuracy of the load cell; resistance strain gauge sticking, curing, group bridge, protection and sealing, circuit compensation and adjustment is to ensure the weighing sensor measurement accuracy The core process. From paste to circuit compensation, no matter which part of the process is not enough, even the best strain gauges will not help.