A weight sensor is essentially a device that converts a mass signal into a measurable electrical signal output. When using a sensor, the first consideration must be its actual operating environment. This is crucial for the correct selection of a weight sensor, as it relates to the sensor's normal operation, safety, lifespan, and even the overall reliability and safety of the weighing instrument. There are significant differences between the old and new national standards regarding the basic concepts and evaluation methods for the main technical indicators of weight sensors.
Structure of a weight sensor
It consists of components such as the instrument (hereinafter referred to as the instrument), weighing sensor (hereinafter referred to as the sensor), connectors, limit devices and junction boxes, and can also be equipped with external devices such as a large screen display, computer and voltage regulator.
Working principle of weight sensor
The object to be weighed or the loaded vehicle is placed on the platform of the weighing device. Under the action of gravity, the load is transmitted to the load cell through the platform, causing the elastic body of the load cell to deform. The strain gauge bridge attached to the elastic body loses its balance and outputs an electrical signal proportional to the weight value. This signal is amplified by a linear amplifier and then converted into a digital signal by an A/D converter. The microprocessor (CPU) of the instrument processes the weight signal and directly displays the weight data. With a printer, the weighing data can be printed and recorded. If a computer is configured, the measurement data can be entered into a computer management system for comprehensive management.
Strain gauges are attached to the elastic body of the load cell, forming a Wheatstone bridge. Under no load, the bridge is in equilibrium, and the output is zero. When the elastic body is subjected to a load, each strain gauge produces a strain proportional to the load. The external load weight can be measured from the output voltage. The instrument can be connected to a host computer via its communication interface.
