Communication problem after installing TP900 Comfort

Hello!

We had PROFIBUS system described below:

CPU 315-2 DP x1 - MASTER
CPU 315-2 DP x2 - SLAVES
EM 277 x9
MP370 x4
TP177A x1

With network settings:

Highest PROFIBUS address: 126
Transmission rate: 1.5 Mbs
Profile: Standard

All units are located in groups over control cabinets interconnected via OLM G12.

After change PROFIBUS system looks like this:

CPU 315-2 DP x1 - MASTER
CPU 315-2 DP x2 - SLAVES
EM 277 x9
Anybus CAN communicator x4 - added
MP370 x4
TP177A x1  - replaced with TP900 Comfort Panel

With network settings:

Highest PROFIBUS address: 40
Transmission rate: 6 Mbs
Profile: Standard

And we implemented FC630 to increase HMI performance.

The problem is with TP900 Comfort Panel. I did migration from TP177A to TP900 and adjusted connection parameters (in Connections). Everything was fine until (I assume) operator did power reset on TP900. After that communication got messed up. Master CPU has started to lose communication, MP370 lost parameters and on some runtime stalled. After TP900 disconnected everything was alright.

What can cause this problem?

Can it be something with "Only master on the bus" because TP177A had this option unchecked but TP900 has it checked and greyed out so I can't change it? I refered to this quote:

From another PLC forum

If you do NOT set the "Only master on bus", a device that is master will check the bus settings before attempting to connect to the bus. If there is then already a master, and this master uses different bus settings, the connection attempt is stopped.

If you DO set the "Only master on bus", the device that is master will NOT check the bus settings before attempting to connect to the bus. If there is then already a master, and this master uses different bus settings, the new master will try to connect, possibly causing a bus failure for the other master.

In other words, I see no reason to select the "Only master on bus". Only advantage would be that the connection would be slighly faster, at the risk of causing bus failures.

In device configuration i left Interface type: MPI but i don't think it's significant.

Maybe interference bacause the unit is near power cabinet? Or faulty unit?

Dear windberry,

please check your commincation settings.

Can you take a screenshot for us  of your communication settings)?

With best regards

rh1990

Hello,

I have encourted the same problem, proxy didn't help. Any further ideas? 

I have tried from TIA V14, V15, I have tried adding HMI in NetPro, I have tried Proxy, I have tried changing DP addresses, I've messed with configuration, checked network using profibus tester and nothing. Oddly, the new panel in profibus tester is going on and and off, on and off. No idea why.