Communication problem over ABB Bailey Infi-net


Thread Starter


Dear All,

I am working in a power plant having a Bailey DCS with an Infi-Net Fiberoptic communication highway (loop). Recently one of our operator station gets in trouble and all communications related to this console is lost (everything turns into purple). Most of the time after a power down and restart of the station, problem is over but it repeats randomly, sometimes with very short intervals. I am suspicious about the loop communication card of that station but to play on it I have to break the loop and bypass that station temporarily. At this time I am afraid of creating bigger problems loosing communication completely together with the other operator station which is the second eye of the operator over the plant while the other one is already gone. Since it is a loop there must be two ways of communication but I am not sure.

What is the best way of breaking the communication loop safely over Bailey infi-net?

I appreciate your help.


martin young

break one loop, bypass the console by reconnecting the 2 open ends. then do the same to the other loop.

I've done this many times without problem.
The infi90 loop is not bidirectional, at least in the twinax or coax wired version. I believe that the fiber setup is similar. Are you running with a redundant loop...that is the best architecture to have, as you can then work on one loop without interrupting loop comms.

If you have a redundant loop architecture, and you are sure it is correctly implemented, you could break the redundant loop at the op station, and put a fiber patch cord in place of the station, re-establishing the loop. Then do the same for the primary loop. The op station will then be out of the loop.

If you don't have redundant loops, I can't think of any way to cut out the station without interrupting the loop comms.
is there any vendor which also use INFI-net beside the ABB? because i want to use DCS from another vendor, not just from ABB. i don't know if Infinet is propietary or open universal system?

thank you for the answer.