controlnet scheduling for redundant PLC system

[yusuf.mavin]

Dear All can anyone please tell the procedure to schedule the controlnet network for a hot standby(redundant) control logix 5563 PLC system? which CNBR card fronm the two racks will be the active keeper? I also heard that the two CNBR cards in the primary rack and the secondary rack should have the same node address. Is it true?

 

[alan_505]

If you get and read the ControlLogix redundancy manual it will tell you everything you need to know, you could also do search of this forum and i am sure this has been discussed and answered before.

Alan

 

[Eddie Willers]

You need to read and understand three documents before you start working on a ControlLogix Redundancy system. All of them are available from the RA Literature Library.

The ControlLogix Redundancy System User Manuals:
http://literature.rockwellautomation.com/idc/groups/literature/documents/um/1756-um523_-en-p.pdf

The Release Notes for your specific release of Redundancy firmware. For example, the Release Notes for version 19.053 Enhanced Redundancy:

http://literature.rockwellautomation.com/idc/groups/literature/documents/rn/1756-rn684_-en-p.pdf

The ControlNet Network Configuration User Manual:
http://literature.rockwellautomation.com/idc/groups/literature/documents/um/cnet-um001_-en-p.pdf

 

[Eddie Willers]

which CNBR card fronm the two racks will be the active keeper?

The keeper-capable device with the lowest ControlNet node number will always be the Active Keeper. It does not matter if it is a 1756-CNBR or 1756-CN2R. It does not matter if it is in a Redundancy system or not.

I also heard that the two CNBR cards in the primary rack and the secondary rack should have the same node address. Is it true?

Yes, a ControlNet module pair in a ControlLogix Redundancy system need to be configured for the same ControlNet Node Number.

When they boot up, they will experience a Node Number Conflict. When the Redundancy modules take over, they automatically reconfigure the modules so that the Primary module is the configured Node Number, and the Secondary module is the configured Node Number + 1.

 

[yusuf.mavin]

Thank You very Much. you cleared my doubt. Thanks a lot.

 

[Oceansoul]

Yes, a ControlNet module pair in a ControlLogix Redundancy system need to be configured for the same ControlNet Node Number.

When they boot up, they will experience a Node Number Conflict. When the Redundancy modules take over, they automatically reconfigure the modules so that the Primary module is the configured Node Number, and the Secondary module is the configured Node Number + 1.

This is also true for any other comms modules in the controller chassis. I.E. Ethernet address must be the same in both enbt cards and the redundancy controller will +1 to the standby chassis.