AB7649-F Eth. IP-Profinet Gateway Stops Transmitting

Our application involves about a dozen AB7649-F Ethernet IP-Profinet gateways and they’re all exhibiting the same behavior. After intital configuration the gateways began talking with the master PLCs on either side, but after about a day they stop talking to the Profinet master. By “stop talking”, I mean the Link light has gone dark and the Profinet master begins reading zeros for all bytes. On the other side, the gateways appears to continue to talk to the Ethernet IP master. We can power cycle the gateways and they all begin receiving and transmitting on both sides again, but after about a day they seem to timeout on the Profinet side. It looks like the gateways timeout because they all stop talking to the Profinet master at the same time.

Is there a configuration setting on the gateway that could contribute to this?

On the Profinet side, the Profinet master PLC is reading from the gateways every 100 ms. We plan on slowing this to a 1 second frequency, hoping that it will help with our disconnect/timeout issue. All writes to the gateway occur on the Ethernet IP side and we haven’t noticed any issues on that side of the gateway. We’ve verified that the Profinet PLC, Ethernet IP PLC, and gateways are all sending/receiving 32 bytes.

Thanks in advance for any advice!

Hi @ddonco,

I believe we have already worked with you on this through the ticketing system and you were able to fix this by increasing the time out on the PROFINET PLC.

Please let me know if you have any other questions.

Best Regards,


We were able to increase the watchdog time on our PCS 7 system (PLCs) and the problem looks to be resolved. The default watchdog time was quite low, 3 ms, which I believe is shorter than the scan time of the gateways, causing the PCS 7 system to disconnect when it thought the gateways were offline.

Thank you for letting us know!