Rockwell Automation 1794-OF8IH FLEX Isolated Input/Output HART Analog Modules - Manual (Page 14)

Publication 1794-UM065B-EN-E - September 2010
2 About the FLEX I/O HART Analog Module
• multiple data ranges that can be independently programmed for each
channel.
• lead breakage detection.
• overrange/underrange alarms.
• remote transmitter alarm.
Communicate with
Programmable Controllers Data connections are established between the FLEX I/O module and an
Allen-Bradley programmable controller (PLC) to transfer information
between the two at a scheduled rate.
Input module information is then automatically made available in the PLC
data table through the data connection. Reciprocally, output data information
determined by the PLC program is also automatically transferred from the
PLC data table to the output module through the data connection.
In addition, when the data connection is originally established, configuration
information for the module is automatically transferred to it via the network.
Events Following Power-up
You must apply +24V DC power to your FLEX I/O analog I/O modules.
The following sequence of events occurs after power has initially been applied
to your module:
1. The module status indicator will blink red until a connection is
established and a valid configuration is passed to the module.
2. After the diagnostic check, module configuration information, selected
by the user and downloaded over the network, is applied by the module.
For more information on configuration options, refer to Configurable
FLEX I/O Analog Module Features.
3. Following the module configuration download for the 1794-IF8IH
module, the module begins producing runtime data for the PLC
processor.
Following the module configuration download for the 1794-OF8IH
module, the module applies configuration data to output channels.
4. If any diagnostics or alarms are generated during normal module
operation, the data is returned to the PLC processor.