On our plant i have total number of 11 nodes. Link of One of Node is down. I attached alarm list. Node 12 is down.. So i plug out NPM and plug in NPM card then link is ok.. My question is that 1st error comes on Node 18 moderror then it comes to other node.. But all other node is ok only node 12 down.
In Infi90 the loop is one way. So a node down message could be coming from an upstream node. Also loop cabling problems may be associated with this issue. Please contact someone within ABB Service to come out and help with this problem. It is too hard to analyse over this forum.
Hi, A node will only report another node down via the N90STA tag if there are explicit communications (an established route) between itself and the node that went down. Whilst a node forwards all traffic on the ring it is really only interested in communication between itself and other nodes with routes established between them. If the node simply halts due to a fatal error, the timing of any alarming by the other nodes is related to the expiration of any Infinet communications retry processes, so can vary from node to node. From your screenshot, PCU 11 and 14 appeared to have alarmed within 60 seconds of the initial PCU18 alarm, which happened several seconds before PCU 12 was reported as offline. Always take note of the LEDs on the failed module and associated NIS as these can be invaluable in determining the cause of the module halt. Your specific failure appears to be related to PCU 12 node hardware only as an Infinet failure would have stopped all traffic on the ring with different results.