Hello all,

I am experiencing an issue with complete Ethernet communication loss for about 5-10 seconds between the PLCs CP modules and the OS servers, and balance of Ethernet S7 and Modbus TCP slaves connected to those CPs. This has so far happened 3x times, each and every time I have attempted it.

The plant is a PCS7 V8.2 non-SP1, running on redundant 410-5H with firmware V8.2.2. with 1x CP443-1 module in each Rack. All Ethernet communications on the plant bus goes through these CP modules, with nothing connected to the CPUs Ethernet ports. Note that OS servers are connected to PLCs with ISO protocol, not IP, while balance of remote S7 and Modbus TCP use IP addressing.

This is a production running plant, and I need the ability to do a bumpless "Connections and Gateways" download such that communications are not interrupted. To my knowledge this was never tested before on this system. Upon selecting "Connections and Gateways" in NetPro, I get a popup prompt asking me to which CPU I wish to download. I always select Rack 0 CPU, which then commences the connections download. During the download process the CPs appear to disconnect and this causes all OS connections to terminated (gray screen and lots of alarms), as well as all remote S7 and Modbus TCP connections to these PLCs to be terminated. Everything automatically comes back on its own once the download is finished, which takes about 5-10 seconds.

The CPU log buffers have no mention of these incidents, while the CPs do. The CP logs indicate the following during the entire cycle of losing to restoring communications:

1. Event ID: 16# F9C1-261D : The system connection to the CPU was terminated actively by the module. Internal Info: 1, External errors, incoming event.

2. Event ID: 16# F9C1-2615: System connection between module and CPU was closed. External error, incoming event.

3. Event ID: 16# F9C1-2614: System connection between module and CPU was established. External error, incoming event.

I am expecting that a "Connections and Gateways" online download is bumpless, per my understanding of system featureset. That being said, is it possible this is occurring due to the ES, OS servers, and balance of remote devices all being connected to CP modules, rather than to the CPUs themselves? Please advise if you have any suggestions or have done this successfully on your own system so I can gauge potential variance.

Thank you for any assistance,

VadRad

Note To Moderator: If possible, please move this topic back to PCS7. This is a PCS7 410-5H specific question, based on doing downloads to a redundant PLC. I feel this would be more relevant and get more applicable use within the PCS7 conference.

Side Comments:

Can someone please advise if they were able to perform these type of downloads successfully without bumping PCS7? I currently have 5x S7 connections, and 9x TCP connections. The amount of data over these connections, aside from the redundant OS to AS connection is minimal. Each other connection is only transferring 10-20 registers worth of data at most.

I am looking to determine if maybe this is too many connections to have on a CP card, or if somehow I need to split the connections between the CPU PN and the CP, etc... Mostly I am interested if anyone has successfully performed these type of downloads without bumping all their other existing connections.

Thank you!

Thanks for the suggestion. I did raise a request, but unfortunately its currently in escalation to HQ, which means it can take some time to make progress.

I posted on here to see if maybe someone has experienced similar situations, or had better luck doing the mentioned download. Currently I don't have a good baseline to know if others are experiencing similar behavior or not. The Siemens manuals and documents have stated conflicting information, with some stating this should be bumpless and others indicated that a bump can occur.