Rockwell Automation Allen-Bradley 1769-IF4, Руководство пользователя

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Publication 1769-UM002B-EN-P - July 2005
Module Data, Status, and Channel Configuration for the Input Modules 3-27
Input Type/Range Selection
This selection along with proper input wiring lets you configure each channel
individually for current or voltage ranges and provides the ability to read the
configured range selections.
Input Data Selection Formats
This selection configures channels 0 through 3 to present analog data in any of
the following formats:
•
Raw/Proportional Data
•
Engineering Units
•
Scaled-for-PID
•
Percent Range
Raw/Proportional Data
The value presented to the controller is proportional to the selected input and
scaled into the maximum data range allowed by the bit resolution of the A/D
converter and filter selected. The full range for a ±10Vdc user input is -32767
to +32767. See Table 3.17 Valid Input Data on page 3-28.
EXAMPLE
2. Two Channels Enabled with Different Filter Settings, But are a Channel Pair
The following example calculates the 1769-IF8 module update time for two channels enabled
with any configuration, with different filter settings, but are a channel pair.
•
Channel 0: ±10V dc with 60 Hz filter
•
Channel 4: 0…10V dc with 500 Hz filter
Module Update Time = [Greater of Channel 0 Update Time or Channel 4 Update Time]
30 ms = [Greater of 30 ms or 6 ms]
IMPORTANT
Configuring the 1769-IF8 module to take advantage of
channel pairs can result in module update times that are
significantly faster than configuring the 1769-IF8 modules
without such channel assignment optimization.