HIEE300885R0102工控模块,HIEE300885R0102产品尺寸
用于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，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。该模块提供两个输入范围。默认范围为4至20 mA，用户数据按比例缩放，使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，
HIEE300885R0102工控模块使0 mA对应于0的计数，20 mA对应于0的计数32000，每800个计数代表0.5 mA。随附两个范围跳线单元一个用于通道1和2，另一个用于通道3和4。四个通道中每个通道的转换速度为半毫秒。这提供了一个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。将A/D转换器的12位放入%AI数据中文字如下所示。电流输入和A/D数据之间的关系转换器如图3-14和3-15所示。如果电流源反向输入，或小于电流范围的低端，然后，模块将输出与电流范围低端对应的数据字（0000H，单位：AI）。如果输入的输入超出范围（即大于20 mA），则A/D转换器将输出至满标度（对应于7FF8H，单位为%AI）。输入比例如下图所示。
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.If the current source is reversed into the input, or is less than the low end of the current range,
then the module will output a data word corresponding to the low end of the current range
(0000H in %AI). If an input that is out of range is entered (that is, it is greater than 20 mA), the
A/D converter will output up to full scale (corresponding to 7FF8H in %AI).
Input scaling is shown in the next figure.
