ICC
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5.10 Modbus Tab
The Modbus tab provides access to configuration items related to communication on a Modbus/TCP
network. Refer to Figure 53.
Figure 53: Modbus Tab
5.10.1 Information Window
Figure 54 shows the Information Window, which is
located in the upper-right hand corner of the Modbus
tab. This window displays various informational
messages regarding the status of the Modbus
configuration parameters (loading or submitting).
5.10.2 Supervisory Timer Selection
Figure 55 shows the checkbox which enables the interface card’s Modbus “supervisory timer” function.
This timer provides the ability for the interface card to monitor timeout occurrences between successive
Modbus/TCP socket connections, as opposed to the standard timeout functionality (refer to section
5.7.6), which monitors timeout occurrences only within the scope of each client socket connection.
While this feature provides an additional level of fail-safe functionality for those applications that require
it, there are several ramifications that must be
understood prior to enabling this capability. Before
enabling this timer, therefore, it is suggested that users
read the ICC whitepaper titled “
A Discussion of
Modbus/TCP Server-Side Timeout Processing
”, which
can be found in the documents section at
http://www.iccdesigns.com.
Figure 54: Modbus Tab Information Window
Figure 55: Supervisory Timer Selection
