二线制带隔离膜片的扩散硅液位变送器

Two-wire transmitter for measuring liquid level based on diffused silicon pressure sensor with insulated diaphragm

由于液位与液体静压力有关 ,因此可以通过静压力测量得到液位的大小。二线制隔离膜片扩散硅液位变送器是利用单晶硅的压阻效应 ,通过电阻的变化 ,得到静压力的大小 ,再通过惠斯登电桥及功能模块电路将静压力转换成电流信号输出 ,从而建立起输出信号与液位的线性对应关系 ,实现对液体深度的测量。还介绍了该种变送器的基本结构。

As the level of liquid is related to static pressure of liquid, level of liquid can be obtained by measuring static pressure.By using piezoresistive effect of monocrystalline silicon, static pressure is sensed with the change of resistance.The transformation of static pressure to output current signal is realized by Wheatstone bridge, and function module circuit, then the relationship that output signal is linear with liquid level is set up.Finally,measurment of liquid level is achieved. Meanwhile,the structure , hermetical method and general application of the transmitter are introduced.