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Modbus tcp redundancy path

Modbus tcp redundancy path

Modbus tcp redundancy path


I have PLC which has to transfer some reading via modbus TCP IP to remote scada,

In my PLC I have only 1 RJ45 ,
But Scada guy wants 2 ethernet cables from me one as failover redundancy.
How can I do this with switch ??
Can someone suggest a switch model and technology required for this ?


RE: Modbus tcp redundancy path

I do this all the time with our substation RTU that has two separate ethernet interfaces. Do you have the option of adding an additional communication interface to the PLC?

RE: Modbus tcp redundancy path

As thermionic1 said, can you add another ethernet interface to your RTU as an option? I would not add a switch, that would only add an additional point of failure which is the exact opposite of what the SCADA guy is trying to do. If you don't have a second RJ45 ethernet option, do you have a second fiber ethernet option? If no options exist just tell the SCADA guy and he will have to live with it.

RE: Modbus tcp redundancy path

Just assume the redundant path is permanently failed winky smile

Adding ANYTHING simply adds a point of failure, and since you've only a single ethernet interface, THAT is the choke point. On PCs you could possibly run an ethernet adaptor to an available serial or USB port.

TTFN (ta ta for now)
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RE: Modbus tcp redundancy path

hi all
i already bought very basic plc, cannto add extension ,

i want to do something with existing single RJ45 port

RE: Modbus tcp redundancy path

He needs 2 Ethernet connections.
He needs to add two Ethernet modules.

What PLC is it?

Keith Cress
kcress - http://www.flaminsystems.com

RE: Modbus tcp redundancy path


I bought ilc 131 eco model phoenix contact


RE: Modbus tcp redundancy path

I have to buy again new

Now ILC131 for sale ,,,,,,,150$ ))))))))

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