OPC UA Redundant Network

Hi M Noman Danish 

IO redundancy in Plant SCADA is actually on IO device level. I assume that these 2 PLCs are not used for operating the same control process. If this is true, you could implement the following IO topology - so called load balancing configuration for redundancy (regardless of protocol).

• Server 1 could be configured to host the primary IO device of PLC1 and the standby IO device of PLC2
• Server 2 could be configured to host the standby IO device of PLC1 and the primary IO device of PLC2

In the healthy condition, each server hosts data from only one PLC (the other one on standby). If one of these two servers is offline, the standby IO will kick in and your SCADA system is still able to acquire data from both PLCs.

Hope this would help.

Regards,

Jacky

Hi M Noman Danish 

IO redundancy in Plant SCADA is actually on IO device level. I assume that these 2 PLCs are not used for operating the same control process. If this is true, you could implement the following IO topology - so called load balancing configuration for redundancy (regardless of protocol).

• Server 1 could be configured to host the primary IO device of PLC1 and the standby IO device of PLC2
• Server 2 could be configured to host the standby IO device of PLC1 and the primary IO device of PLC2

In the healthy condition, each server hosts data from only one PLC (the other one on standby). If one of these two servers is offline, the standby IO will kick in and your SCADA system is still able to acquire data from both PLCs.

Hope this would help.

Regards,

Jacky

We have 2 PLCs these two PLCs are not used for operating the same control process. We are communicating these two PLCs with SCADA by OPC UA protocol.

In the case of Server shutdown /Fail For that we have 2 servers in our network. If Server 1 fails then our second server start communication with the PLCs vice versa.

Kindly check the following configurations is it right to do this :

Server 1 could be configured to host the primary IO device of PLC1 and the primary IO device of PLC2.
Server 2 could be configured to host the standby IO device of PLC1 and the standby IO device of PLC2.

Kindly also provide help about boards and ports for both servers

Here is an example of board, port and IO device configurations for OPCUA redundant paths. Hope it would help.

You can also to add your OPCUA devices using Device Communication Wizard as shown below.

 Jack we have this scenario where we have two PLCs (working for different operations ).

communication protocol is OPCUA. we need only IO server Redundancy.

You said there are two servers in your system. In my example, IOServer1 should be hosted by your server machine 1 while IOServer2 is hosted by server machine 2. The diagram you attached is not entirely accurate as IO redundancy is achieved on IO device level. Just treat IO Server (Primary) as IO Server 1 while IO Server (Standby) as IO Server 2 as described in my example..

For the  IO server Redundancy. kindly check the below attached snaps this configuration  will work or not  ?

Hi M Noman Danish ,

Yes, it should work. Only difference between yours and mine is that Scada_Server_1 hosts both primary OPCUA IO devices while the standby IO devices are the other machine.

Yes Jacky I am working with 72 PLCs Communication protocol is OPCUA only 

I created Scada_Server_1 host all PLCs as a primary and Scada_Server_2 host all PLCs as a standby

kindly if possible suggest some solution for other IO devices communication .

OPCUA is not telemetry protocol is it possible using some MQTT broker and connecting all devices with broker and then this MQTT broker with plant SCADA .

Thanks Jacky for conformation.

Unfortunately, MQTT protocol is not supported in Plant SCADA at moment.