Mechanical mixing equipment works with the selection of load cell This paper engineering machinery mixing equipment weighing system and the basic requirements for special requirements, proposed construction machinery mixing equipment weighing system used to be considered when the sensor several issues, the focus of sensor protective structure on the construction machinery mixing equipment reliability of operation, pointing out that the code generation IP Table protective levels can not cover mechanical mixing equipment works full protection of the sensor requirements. Recommendations different types of mixing equipment selection of different defensive capabilities of the sensor. Weighing System sensors normally used in the weighing system to consider the amount of limited accuracy, sensor installation space, the environment may affect the sensor, load and the type of sensor, such as the life span of various factors. Engineering machinery mixing equipment weighing system is no exception. The weighing system is different because of different demands, different working conditions, to be considered by focusing on different issues only. Engineering machinery mixing concrete mixing equipment usually include floor (stations), the asphalt mixing plant, stabilized soil mixing concrete mixing plants and ships at sea, mixing them with concrete floor (stations) the most typical. Below the concrete mixing plant (stations) as an example for analysis. 1 concrete mixing plant (station) on the basic requirements Weighing System 1.1 accurate weighing error on the strength of concrete is strongly influenced, in particular water-cement ratio measurement precision, because strength and water-cement ratio is linear. The relevant national standards, cement, water, additives, the admixture of dynamic measurement accuracy of 1%, sand, stone dynamic measurement accuracy of 2%. 1.2 Quick meet mixing station duty cycle requirements. 1.3 variety that money to the type of pre-selection, to facilitate the transformation to adapt to a variety of different ratio and capacity requirements. 1.4 simple structure weighing devices to simple structure, solid and reliable, stable performance, easy operation. Clearly, the use of electronic weighing system sensor machinery weighing more than meet the requirements. Therefore, the load cell floor in the concrete mixing stations to be more widely used. However, objectively speaking, compared with the mechanical lever scales in the solid and reliable, stable performance, as a sensor electronic weighing system has much work to do. 2 concrete mixing stations floor in the load cell operating conditions For commerce and the general measurement of electronic scales a great difference is, in concrete mixing stations floor load cell in a very adverse operating conditions, stress environment is very complex, and the general electronic products compared to the operating environment, a greater randomness. 2.1 ambient temperature and humidity Concrete mixing station is normally open floor installation, sensor may be subject to the sun and rain, temperature dramatic changes. And many construction projects are in very bad natural conditions in the mountains or remote areas. Therefore, we must consider greater temperature range and higher humidity conditions. Concrete in the production process needs water. In the delivery of water and weighing process and also have a lot of water in the gas, in some form within relatively small humid environment. Stir in the temperature control in the House, there are high-temperature and low-temperature conditions of the different requirements of condition. Running in the summer when low-temperature condition to the zero-below cold wind and加冰stirring, then building a condensed water will be well demonstrated high humidity building. 2.2 dust Concrete in the production process requires a large amount of cement, coal ash and the appropriate amount of admixture. These were in the transportation and powder weighing process will produce dust. Even the aggregate, in the course of transmission have also dust. Some of these dust sensor will be attached to the surface. The dust and water vapor in the common role, the sensor will be more serious corrosion. Therefore, the damage powder weighing sensors usually weigh than the other sensors more frequently. 2.3 Shock and Vibration In the feed process, the impact of aggregate will have. Sensors should be able to bear 5 g acceleration. Stir in the process, will have sustained vibration, and vibration would have fatigue damage. 2.4 man-made environment Man-made environment is the product reliability design one of the factors that must be considered. Concrete Mixing floor installed at the construction site in general. Large-scale use of temporary workers on site, of which a considerable number of temporary low level of education, lack of the necessary skills. In te