Connecting Ignition to PCS 7 S7-400 – Best Practice for Stable Tag Addressing?

We have a customer running PCS 7 with WinCC on an S7-400 controller and they would like to display some of the same process data in Ignition as well.My initial thought is to connect Ignition directly to the S7-400 using Siemens S7 communication and absolute addressing.

However, I have a concern regarding PCS 7 compilations. As far as I understand, DB numbers can change during engineering changes or recompilation. If Ignition tags are configured using absolute addresses (e.g., DBx.DBXy, DBDy, etc.), any DB number changes would require updating the corresponding tag addresses in Ignition.

For those who have integrated Ignition with PCS 7 systems:

  • Is direct S7-400 absolute addressing a common and reliable approach?
  • How do you deal with DB number changes after PCS 7 compilations?
  • Are there recommended methods to maintain stable tag addressing when connecting Ignition to a PCS 7 system?
  • Is there a better approach than referencing PCS 7-generated DBs directly?

I'd appreciate any insights or best practices from those who have done similar integrations.

I would try to pursue OPC UA (if your PCS 7 system is somewhat up-to-date). As with everything else in PCS7, you'll need an additional license for that software package (OpenPCS 7).

If it really is an S7-400, then absolute addressing is your only choice. Those old architectures do not expose symbolic names.

Its PCS7 V9.1 . Absolute addressing is the way but i am worried about DB number which changes when we do compilation in PCS7.

Got it . Any way without OPC_UA. Since OPC UA license cost will be extra.

Disclaimer, this was several years ago (I stopped renewing my PCS7 certification >5 years ago)... but, I recall setting up an OPC DA connection (no extra license required, provided your Ignition server is on Windows, and you're willing to work with DCOM & all the headaches you might encounter) between Ignition 7.9 & a PCS7 Operator Station (WinCC).
This was at a Uranium mining plant, and the H-station controller network was not accessible to the Ignition server, but an OS Server was...so it was the only option I had (probably would have been my preferred approach regardless).