System redundancy and profibus redundancy

Hello,

currently we use two X20 PLC to have system redundancy with Modbus redundancy ( Modbus ring with two modules for each PLC, total four modules).
Now we want to implement Profibus redundancy with two Profibus lines per PLC. Every PLC has one module per line, also total four modules.
Only one module can be the active master and the others have to be passive.

Is it possible to achieve this with the X20IF1061-1 module? To set it active/passive from the PLC?

Also we need two different Profibus networks, which means we would need four Profibus master for each PLC. Can so many modules be connected to one PLC?

Thx for your help
Benjamin

Hello,
please take a look at the redundancy chapter of AS online help:
B&R Online Help

This means 4 masters per PLC is not possible as X20 PLCs only offer up to 3 slots where one slot needs to be used for the redundancy link module IF10X0

Typical topology would then be:
B&R Online Help

In other words if you have PLC redundancy AND no PLK IOs you could operate 2x IF1061-1 in the PLC but this is the maximum
Switching of the IFs is not done by your application. Whenever the active PLC fails the standby PLC will take over and also acivate the IF1061-1 to take over Profibus. Nevertheless if you plug 2x IF1061-1 in one PLC then this are 2 seperate Profibus networks but not redundant if one of the IFs fail

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Thank you.

This helps a lot and I was missing this information in my search.

Of course I already have two seperate Profibus networks with two interface but as we use also devices with slave redundancy (two Profibus slave modules per device) we need per PLC two IF for one “device network”. This information was missing in my explanation.
But as mentioned we also want two “device networks” which than would be a total of four IFs. But as you mentioned this is would not be possible.

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You are very welcome !