【摘要】 针对常用的电阻应变电桥式称重传感器输出电压信号变化极为微小(若干毫伏)、零位误差较大(与输出变化量相当,甚至大于输出电压变化量),不便于转换和传输的问题,为了将电阻应变电桥式称重传感器信号转换为两线制4~20m A电流信号进行输出,采用基于仪表放大器AD627和电流转换器XTR105的模拟电路转换方案,对信号进行放大、零位偏差补偿。通过V/I转换器,把电压信号转换成电流输出信号,有利于长距离传输。详细介绍了变送器的工作原理和硬件电路设计。通过测试实验验证了变送器的测量特性。更多还原

【Abstract】 Considering the tiny change(several millivolts) in output voltage signals,obvious zero offset(equal to or greater than the output voltage) and inconvenience in conversion and transmission of the commonly-used resistance strain bridge-type weighing sensor,and for purpose of converting its output signals to 4 ~ 20 m A current signals with a two-wire output form,a AD627 instrument amplifier and XTR105 current converter-based analog circuit conversion scheme was proposed to magnify signals and implement zero offset compensation;meanwhile,through V/I converter,it has voltage signals converted into current output signals for long-distance transmission. The working principle of the transmitter and the design scheme of the hardware circuit were introduced in detail. The test results verify the measuring characteristics of this transmitter.更多还原