How to find the trouble shoot the third node??

Hello Everyone,

I have faced a problem: the project consists of 3 S7-300 PLC's connected by MPI. CP5611 installed in HMI Wincc. PG/PC interface is CP5611 MPI. I opened simatic manager without any project opened..i clicked accesible nodes and I found only nodes 2&3...node 4 is missing...I checked the termination switch position and everything in hardware side and I found no problem...After further investigation, my technician said that he had copied system data of one plc(node 3) into a plc(node 4) and downloaded it (he has done this because both plc's are identical in every respect)....Now I am in trouble...I cannot see the third node...I have backup but I don't need to proceed further...

Please help me how to copy the backup in steps..

thanking you.

I suspect he wrote over node 4's address. I bet you have two address 3's now. The system data contains the hardware config. of each station.

Hi JRW,

No I did not have two address of three (3)..Advice me how to start from the scratch?

Try this test

Disconnect MPI cable from all CPU's and connect into each CPU's MPI port and try accessible nodes each (one at a time) and see what the addresses are-

Hi,

I tried removing the MPI cable and observed that node 2 and node 3 are comming and going while connecting and disconnecting them..but at node 4 is not comming with that procedure..

Can you connect into node 4 (only node 4) and try accessible nodes
What positions are the termination resistors in?
The terminations should only be on at the ends (when one wire is connected at the device)

I read your first post again- but I still suspect (if it had been working before the system blocks folder was re downloaded) that its an address problem.

JRW said:

Can you connect into node 4 (only node 4) and try accessible nodes
What positions are the termination resistors in?
The terminations should only be on at the ends (when one wire is connected at the device)

Click to expand...

No Node no.4 is not recognized..

Connect PC to node 4 ONLY and try accessible nodes

Did this system work BEFORE the system data was copy to Node 4

JRW said:

Connect PC to node 4 ONLY and try accessible nodes

Did this system work BEFORE the system data was copy to Node 4

Click to expand...

I donot know that...As far as I belive the system data consists of hardware and blocks..and I have done memory reset for all cpu's...but still i am able to see only node no.2 and 3 only..I wonder how this is being displayed, since there is no program in all cpu's how the system is showing these nodes??