Hello,

I am encountering an very strange error that I would like some help with.  

We have a S7-1500 (1516-3 PN/DP) with a network of Profibus nodes connected to the X3 port.  Most of the nodes are ABB UMCs and VFDs, however one node on the network is a Beckhoff CX8031 Profibus Slave.  All nodes including the Beckhoff usually communicate correctly and no diagnostic faults are present on the controller.  As soon as I go online with TIA V15 via the X1 Profinet port, the Beckhoff node starts experiencing intermittent errors.  The errors are quite general and state "I/O Device Failure".   As as I go offline, the CPU error light changes state to healthy and everything is OK.  Input words being read from the Beckhoff slave will flip to zero briefly, so there is an actual read error.  

What I cannot understand is how connected to the CPU via a different media (Profinet) can cause profibus errors such as the ones I am experiencing.  I tried creating a blank project from scratch with only one node on the network.  I even connected a cable directly from the CPU to the Beckhoff slave to eliminate the possibility of node conflicts or media issues.  

Our chassis also has a separate profibus CP card.  For the sake of troubleshooting I connected the Beckhoff slave to the CP card and did not experience any errors while online.  

Is this a bug in TIA?  Is there a common connection resource? 

The CPU firmware revision is 2.1 and I am using TIA V15 Update 1

Thanks for the help

Hello adam;

Very interesting problem indeed. I have never seen any instance of such an interruption of one node on a Profibus network affected by the use of another fieldbus connection.

At first glance I would suggest this is probably an issue that should be brought to the attention of a Siemens tech. You can start a Support Request (use the link at the top of this page) and enter as much information as you can so they can have a complete view of the installation, hardware and software. Actually, your thread starter seems quite complete.

In the meantime, someone here may have a suggestion when we have examined the post better.

Hope this helps,

Daniel Chartier

Thank you Daniel, 

I contacted Siemens support and will post my findings on this thread.   

Hi All,

I had this exact fault using TIA portal V14 SP1

Had a 1515-2PN CPU and a CM1542-5 Profibus module in the rack 

8 x ABB FPBA-1 Profibus slaves on the network. 

ABB nodes kept dropping off when i went online in TIA Portal direct at Slot X1.

Got in touch with ABB and they suggested changing the GSD file from ABB10959.gsd

to a ABB0959.gsd

It fixed the problem. 

Something to do with DPV0 and DPV1. #

Attached the GSD files sent to me by ABB

Hi,

we are experiencing same problem with S7-1515-2 PN and CM1542-5 as a master and ABB IO CI801 as a slave. Can u share a solution? We tried different GSD files for ABB but same result: loosing connection via profibus when we are online with TIA Portal but via Ethernet on CPU.

 

 Hi cs3,

did you read the whole topic? Please read the offered solution by rjones and tell us where you get stuck. 

rjones

Hi All,

I had this exact fault using TIA portal V14 SP1

Had a 1515-2PN CPU and a CM1542-5 Profibus module in the rack 

8 x ABB FPBA-1 Profibus slaves on the network. 

ABB nodes kept dropping off when i went online in TIA Portal direct at Slot X1.

Got in touch with ABB and they suggested changing the GSD file from ABB10959.gsd

to a ABB0959.gsd

It fixed the problem. 

Something to do with DPV0 and DPV1. #

Attached the GSD files sent to me by ABB

Yea, i read...

We contacted with ABB and they gave us new GSD. We still have drop in connection between PLC and IO ABB (only when we are online in TIA Portal - via Profinet - what is totaly confusing us, couse Profibus is on CM module, and we are connecting via PLC network card).

I'm experiencing the same issue in TIA Portal V17 using a 1516-3 PN/DP CPU with ABB CI801 slaves connected via Profibus.

The system runs stably until I go online with the hardware configuration in TIA Portal over Ethernet. At that moment, the Profibus slaves drop out briefly—typically for a few hundred milliseconds—before reconnecting. This seems to be triggered when accessing module status, as if "opening" the slave modules causes the interruption.

Are there known solutions or workarounds to prevent the slave dropouts when going online?