PP845 3BSE042235R1触摸显示屏,3BSE042235R1用户手册
90-30系列可编程逻辑的4通道模拟电流输入模块
控制器提供四个输入通道，PP845 3BSE042235R1每个通道能够将模拟输入信号转换为
根据应用要求使用的数字信号。此模块提供两个输入范围。
默认范围为4至20 mA，用户数据经过缩放，因此4 mA对应于0计数
20 mA对应32000个计数，每1000个计数代表0.5 mA。什么时候
在输入/输出端子板上添加跳线，输入范围随用户更改为0至20 mA
对数据进行缩放，使0 mA对应于0的计数，20 mA对应于
32000，每800个计数代表0.5 mA。配有两个量程跳线PP845 3BSE042235R1触摸显示屏
单元一个用于通道1和2，另一个用于通道3和4。
四个通道中的每个通道的转换速度为半毫秒。这提供了
任何通道的两毫秒更新率。转换信号的分辨率为12位
任意范围内的二进制（4096中的1部分）。%AI寄存器中的用户数据为16位2
补码格式。A/D转换器的12位在%AI数据中的位置
word如下所示。当前输入与A/D数据之间的关系
转换器如图3-14和3-15所示。
The 4-Channel Analog Current Input module for the Series 90-30 Programmable Logic
Controller provides four input channels, each capable of converting an analog input signal to a
digital signal for use as required by your application. This module provides two input ranges.
The default range is 4 to 20 mA with user data scaled so that 4 mA corresponds to a count of 0
and 20 mA corresponds to a count of 32000 with each 1000 counts representing 0.5 mA. When
a jumper is added to the I/O terminal board, the input range is changed to 0 to 20 mA with user
data scaled so that 0 mA corresponds to a count of 0 and 20 mA corresponds to a count of
32000 with each 800 counts representing 0.5 mA. Two range jumpers are provided with the
module; one for channels one and two, and the other for channels three and four.
Conversion speed for each of the four channels is one-half millisecond. This provides an
update rate of two milliseconds for any channel. Resolution of the converted signal is 12 bits
binary (1 part in 4096) over either range. User data in the %AI registers is in 16-bit 2’s
complement format. The placement of the 12 bits from the A/D converter in the %AI data
word is shown below. The relationship between the current input and the data from the A/D
converter is shown in Figures 3-14 and 3-15.
