ProSoft Technology PLX8X-MNET-61850 - Manual (Page 102)

Diagnostics and Troubleshooting PLX8x-MNET-61850 ♦ Communication Gateway
User Manual Modbus TCP/IP to IEC 61850
Page 102 of 228 ProSoft Technology, Inc.
May 14, 2014
5.2 Important Design Considerations
When utilizing any type of gateway device, careful consideration should be taken
to make sure that in the event in loss of communications between devices on
either the Modbus TCP/IP driver or the 61850 driver, this loss of communications
is passed to the other driver.
Say for instance you have a loss of communications with an IED device on the
61850 network. This information should be shared with the Modbus TCP/IP
device, so that the device can make an informed decision as to if they need to
trigger any type of alarm or fail safe state for the attached device.
All applications should make careful consideration of each of the status words
available to the various drivers. No application should be configured into a live
system without mapping the driver status words and IEC 61850 IED status
registers described below.
Additionally, if a Modbus TCP/IP client (like a Quantum, Premium, or M340 PLC)
is issuing control commands to the ProSoft gateway as a Modbus TCP/IP server,
then that device should also monitor its status information to make sure that this
information is written to the module.
The reporting of this status information is crucial to the setup and configuration of
a live system. Without mapping status data to the various drivers, it is impossible
to tell if communications is actively occurring with the device, or if the data values
are stale, and simply represent the last known conditions of that device.
Driver status, IED status, and client/server status information should be shared
with the various drivers to ensure that a clear indication of loss of
communications can be signaled to the devices on the network.