A few weeks ago we hosted a webinar together with the PIC (PROFI-Interface Center) about PROFINET Diagnostics. We had many attendees and several of them had very interesting questions during the webinar. As a recap and a way to sum up most of the questions, we have answered them below.
Q&A
1.-Is there a generic level of alarm tag (ex. maintenance required) contained in the real-time telegram?
Yes, the alarm message information does not only include the type of alarm (device, network, process), but also the priority.
2.-What advantages can a PROFINET Managed Switch provide in comparison with an Industrial Managed Switch (non-PROFINET)?
Industrial managed switches are rugged smart devices with many diagnostics capabilities. PROFINET managed switches offer an additional advantage since they will look like IO to the PLC. This means the switch will have a GSD (General Station Description) file just like any other PROFINET device. The GSD file defines what diagnostic information available. For example, if a device unplugs from a switch port, the PLC logic can execute an appropriate action.
3.-Under high load conditions can you guarantee every telegram will be copied to a mirror port?
It is possible that you can lose a telegram during high load times since the port mirroring messages have lower priority on the switch. If you think you may encounter this issue use a TAP or other advanced capture tool to prevent losing information.
4.-Can you mirror a port that is currently part of a ring for diagnostics information?
Yes, depending on the vendor you can mirror a port that is part of a ring topology. You will observe traffic directed to that specific port as specified in your topology setup. Something to take in consideration would be latency. If the network load is high, frames could be missed, but as mention in the previous question, a TAP can resolve this.
5.-Apart from a digital scope, is there a tool available to view electric waveforms?
For this, you would need an O-scope as Ethernet signals can be quite complex. These PROFINET diagnostics capabilities may only apply when developing a specialized product.
6.-Where can I find advanced capture tools (TAP, continuous monitoring, etc)?
Those tools are available from many vendors. You can start searching for these products in our Product Finder (https://www.profibus.com/products/product-finder/), but ultimately searching the web or your preferred vendor website may be your best bet.
If you would like to learn much more, watch the full on-demand webinar:
-Nelly Ayllon