Let's learn about the composition of the load cell.

1. Sensitive element

An element that directly feels the measured (mass) and outputs other quantities that are confirmed to be related to the measured. For example, the elastic body of the resistance strain type weighing sensor transforms the mass of the measured object into deformation; The elastic body of capacitive weighing sensor converts the measured mass into displacement.

2. Transformation element

Also known as sensing element, it converts the output of the active element into a signal that is convenient for measurement. For example, the resistance strain gage (or resistance strain gauge) of the resistance strain type weighing sensor converts the deformation of the elastomer into the change of the resistance; The capacitor of capacitive weighing sensor converts the displacement of elastic body into the change of capacitance. Sometimes some elements have the functions of both active elements and switching elements. For example, the piezoelectric data of voltage-type weighing sensor, under the action of external load, produces deformation and outputs electricity at the same time

3. Measuring element

The output of the conversion element is converted into an electrical signal, which is convenient for further transmission, processing, display, recording or control of supply. Such as the bridge circuit in the resistance strain type load cell and the charge preamplifier of the piezoelectric load cell.

4. Auxiliary power supply

Energy is supplied for the electrical signal output of the sensor. Generally, weighing sensors need external power supply to operate. Therefore, as a product, it is necessary to indicate the requirements of power supply, but it is not an integral part of the weighing sensor. Some sensors, such as magnetoelectric speed sensors, can work normally without auxiliary power supply because of their large output energy. Therefore, not all sensors need auxiliary power supply.