Rockwell Automation Allen-Bradley 1769-IF4, Руководство пользователя

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Publication 1769-UM002B-EN-P - July 2005
Configuring Modules in a Remote DeviceNet System with a 1769-ADN DeviceNet Adapter D-9
1769-OF8C Example of Output Channels
Each of the two analog output channels are disabled by default. To enabled a
channel, click its Enable box so that a check mark appears in it. Then, choose
your Output Range, Data Format, and the state or your outputs should the
controlling processor be placed into the program mode, fault, or lose
communications.
Program State and Fault State each have two options:
•
Hold Last State
Hold last state will hold the analog output at the last value received
before the processor was placed in program mode or before it faulted.
•
User-defined State
When selecting user-defined state, you must specify a value for the
analog output to revert to should the processor be placed in program
mode or fault. The values used for user-defined state must be valid
values determined by the selected Data Format and Output Range. If
communications fail, you may also choose whether your Program State
or Fault State options take place for each channel.
In this example, channels 0 and 1 are enabled and configured for 4 to 20 mA
Output Ranges. The Data Format for channel 0 is Scaled-for-PID, because it
is the CV (output) value from your PID instruction. Hold last state was chosen
for all possible conditions other than Run mode for channel 0.
Channel 1 is also enabled and configured for 4 to 20 mA Output Range.
Raw/Proportional Data Format was chosen for maximum resolution. In
addition, a requirement of the system is that this analog output must always be
at 4 mA if the system is not in control of it.