S7+ Driver Tag Limit

emaddocks · Post by **emaddocks** » Wed Jan 24, 2024 11:03 am

We seem to have come across a bug or limitation of the S7+ driver. When there are a small number of tags and we disconnect our S7-1500 PLC the driver picks up the comms failure in a reasonable amount of time (less than 20 seconds). However when we have a large number of tags (more than 20,000) doing the same test results in the S7+ driver taking 15 minutes to pick up the connection and sometimes during this 15 minutes the driver in the OA Console is purple and the log viewer reports that it is a 'Blocking Manager'.

Are there any limitations to the number of tags that can be in a poll group or on a driver?

We are running WinCC OA 3.18 Patch 4 on RHEL 8.4.

I have also raised this issue with Siemens support directly.

emaddocks · Post by **emaddocks** » Tue Mar 26, 2024 11:46 pm

This is a bug with the S7+ Driver. It was fixed in WinCC OA 3.18 Patch 24.

Bugs / Problems