Siemens PLC (S7-300) unable to detect the connected node via CANBUSS

AB2005

Member
Join Date
Nov 2006
Location
Soth Asia
Posts
310
Dear Friends;

We have a BOBST 1228 flexo printing machine having Siemens S7-300 PLC (6ES7 318-3EL01-0AB0) and Lenze 9300 and 9400 drives. The field I/Os, Drives and an HMI is connected with PLC via CANBUSS. There are four CANBUSS cables going from PLC to field. At one of those cables, 34 nodes are connected. The last node (#05) is a Siemens HMI where termination resistance is connected at connector.

We faced a problem which appeared during running of machine that Main PC showed a fault that node 05 (HMI) was disappeared while it was connected. We replaced that HMI with a brand new tested HMI but hence problem was there. We tested all the CANBUSS network and connector but all the things were OK. We guessed that some problem appeared in PLC program. OEM connected via VPN and they also diagnosed the same but they unable to resolved the issue and stated that as the program can not be downloaded via VPN into PLC (program is in a memory card). They will send a new memory card of PLC with updated program.
Now we are waiting for that memory card.

This is strange for me that what kind of problem appeared in PLC program that it is not detecting the Node 05. Second thing, why OEM is not able to detect the problem and then download the program in PLC via VPN while it is our normal practice with other machines where other OEMs can do the same very easily with Allen Bradley PLC.

Can anyone help me out to understand the issue?
 
We have a BOBST 1228 flexo printing machine having Siemens S7-300 PLC (6ES7 318-3EL01-0AB0) and Lenze 9300 and 9400 drives. The field I/Os, Drives and an HMI is connected with PLC via CANBUSS. There are four CANBUSS cables going from PLC to field. At one of those cables, 34 nodes are connected. The last node (#05) is a Siemens HMI where termination resistance is connected at connector.

Are you SURE that it's CANBUS? If so, how is the PLC connected to it, perhaps via a gateway? Siemens PLCs don't communicate via Canbus natively. Could it be Profibus? Is the cable purple?

We faced a problem which appeared during running of machine that Main PC showed a fault that node 05 (HMI) was disappeared while it was connected. We replaced that HMI with a brand new tested HMI but hence problem was there. We tested all the CANBUSS network and connector but all the things were OK. We guessed that some problem appeared in PLC program. OEM connected via VPN and they also diagnosed the same but they unable to resolved the issue and stated that as the program can not be downloaded via VPN into PLC (program is in a memory card). They will send a new memory card of PLC with updated program.
Now we are waiting for that memory card.

It is definitely possible to download to a 319 over a VPN, IF the network is set up correctly.

However, if there is a gateway, that could prevent VPN downloads. It's also possible that the OEM's standard procedure is to send a new memory card instead of the VPN download, and they simply don't want to. There are hypothetical risks associated to downloading to a PLC of any brand over a VPN, if the connection fails.
 
Are you SURE that it's CANBUS? If so, how is the PLC connected to it, perhaps via a gateway? Siemens PLCs don't communicate via Canbus natively. Could it be Profibus? Is the cable purple?

Yes. The cable is purple and thus network is Profibus. I was wrong.
Today we received the new memory card sent by OEM but problem is same with the new memory card. System doesn't detect the HMI.
We have changed the position of HMI and connected it
With other comm connector where the drives connected but hence system doesn't detect it.

Can anyone help?
 
Hi;


After a 12days long breakdown, we have found the problem in an INPUT card (6E7 321-1BH02-0AA0)connected with main CPU. There was no link between the infected HMI which was connected with CPU via Profibus and the faulted input card. But with PROFIBUS, everything is possible.


Thats why i dont like Profibus but dont know why OEMs have been continously using it.
System was showing error that the node 5 (HMI) is not connected but fault found in an input card. its mean in future we can not rely on system messages. we will have to keep the inventory of all electronics items.
 

Similar Topics

Hello. There is a problem with Siemens S7 300. We got a replacement PLC but it does not run the program from the MMC. The new PLC is dated 2011...
Replies
3
Views
661
Is there a version of Siemens software that can be used to view only the installed program logic and diagnostic buffer to determine system and bus...
Replies
5
Views
2,035
I set the Date and Time of the S7 300 PLC equal to that of my PG. But after a few days I found that the date and time were not what they should...
Replies
0
Views
1,905
Hi Can any one give me some of sample project file for Siemens S7 300 PLC that I can practice at home. Thanks in Advance
Replies
2
Views
2,759
Hi Sir, I am using S7-300/400. I am usually using FC 03 and FC04 to transfer (R/W) bool values by moving them DBs. However i want to R/W bool...
Replies
1
Views
2,042
Back
Top Bottom