How to choose a load cell - Solutions - Huaqiang Electronic Network

inductance

The load cell is known as the heart of the electronic weighing instrument, and its performance largely determines the accuracy and stability of the electronic weighing instrument. When designing an electronic scale, it is often a problem to choose a sensor. A load cell is actually a device that converts a quality signal into a measurable electrical signal output. In the actual working environment where the sensor is located, it is important to select the correct sensor. It is related to the normal operation of the sensor, its safety and service life, and the reliability and safety of the entire scale. The selection of the sensor range can be determined based on the maximum weighing value of the scale, the number of selected sensors, the weight of the scale body, the maximum eccentric load that can be generated, and the dynamic load. In general, the closer the sensor's range is to the load assigned to each sensor, the higher the accuracy of its weighing. However, in actual use, since the load applied to the sensor is in addition to the object to be weighed, there are loads such as weight, tare, eccentric load and vibration shock of the scale body. Therefore, when selecting the sensor range, various factors should be considered to ensure Sensor safety and longevity. According to experience, the sensor should generally be operated within its 30% to 70% range. However, for some scales that have a large impact during use, such as dynamic rail scales, dynamic truck scales, steel scales, etc., when selecting sensors, it is generally necessary to expand the range so that the sensor is 20% to 30% of its range. Internal work, the sensor's weighing reserve range is increased to ensure the safety and longevity of the sensor. The choice of sensor type depends mainly on the type of weighing and the installation space, to ensure proper installation, and the weighing is safe and reliable; on the other hand, the sensor manufacturer's recommendations should be considered. Manufacturers generally specify the scope of the sensor according to the force of the sensor, performance indicators, installation form, structure type, material of the elastomer, etc. For example, the aluminum cantilever beam sensor is suitable for price scales, platform scales, case scales, etc., steel The cantilever beam sensor is suitable for hopper scales, electronic belt scales, sorting scales, etc. Steel bridge sensors are suitable for railway scales, truck scales, crane scales, etc. Column sensors are suitable for truck scales, dynamic rail scales, large tonnage hopper scales. Wait. In addition, the selected sensor must meet the input sensitivity requirements of the instrument and must be able to match the selected instrument to meet the accuracy requirements of the entire electronic scale. An electronic scale is mainly composed of three parts: mechanical mechanism, sensor and instrument. When selecting the accuracy of the sensor, the accuracy of the sensor should be slightly higher than the theoretical calculation value, because the theory is often limited by objective conditions, such as machinery. Factors such as the strength of the structure, the performance of the instrument, and the harshness of the working environment of the scale directly affect the accuracy of the scale. Therefore, it is necessary to raise requirements from all aspects, take into account economic benefits, and ensure that the objectives are achieved.