Views: 2 Author: Site Editor Publish Time: 2022-05-27 Origin: Site
The output characteristic of the SAINTBOND load cell is non-linear. Although the differential type is used to improve it, it is impossible to completely eliminate it. The output characteristics of other types of capacitive sensors are linear only when the edge effect of the electric field is ignored. Otherwise, the additional capacitance generated by the edge effect will be directly superimposed on the sensor capacitor, making the output characteristic nonlinear.
The initial capacitance of the capacitive load cell is small, and the so-called parasitic capacitance, such as the lead capacitance connecting the sensor and the electronic circuit, the stray capacitance of the electronic circuit, and the capacitance formed by the inner plate of the sensor and the surrounding conductor, is large, which not only reduces the sensor The sensitivity of the instrument, and these capacitances are often randomly changed, which will make the instrument work very unstable and affect the measurement accuracy.
The capacity of the SAINTBOND load cell is limited by the geometric size of its electrodes, etc. It is not easy to be very large, generally tens to hundreds of microfarads, or even only a few microfarads. Therefore, the output impedance of the SQB load cell is high, so the load capacity is poor, and it is easily affected by external interference to cause instability, and it may even fail to work in severe cases.
Electronic weighing instruments made by load cells have been widely used in all walks of life, realizing fast and accurate weighing of materials, especially with the appearance of microprocessors, the automation of industrial production processes continues to increase. Weighing sensors have become a necessary device in process control, ranging from weight measurement of large tanks and hoppers that could not be weighed before, and measurement and control of crane scales and automobile scales, to batching systems that mix and distribute multiple raw materials, The automatic detection in the production process and the control of the powder and granular material feed amount are all applied to the load cell. At present, the load cell is used in almost all weighing fields.
It is caused by the device itself, including the DC drift value, the incorrect slope or the non-linear shape of the slope. After all, there will be a gap between the ideal transfer function characteristics of the device and the real characteristics.
That is, errors caused by operation, including incorrect placement of probes, incorrect insulation between the probe and the measuring location, errors in the purification process of air or other gases, incorrect placement of transmitters and other operating errors. The error.
The SAINTBOND load cell suitable for static conditions has strong damping, so it responds slowly to changes in input parameters, and even takes a few seconds to respond to a step change in temperature. Some load cells with delay characteristics will produce dynamic errors when responding to rapid changes. Response time, amplitude distortion, and phase distortion all cause dynamic errors.
It is the error caused by changing the measurement parameters when a sensor is inserted into the system. Using a transmitter that is too large for the system, the dynamic characteristics of the system is too slow, and the self-heating in the system loads too much heat, etc., will cause insertion errors.
The use of the SAINTBOND load cell is also affected by the environment such as temperature, swing, vibration, altitude, chemical substance volatilization, etc. These factors can easily cause environmental errors.