SIMATIC WinCC Open Architecture Forum

Hi,

Is there a limit on the number of dpConnects in a UI panel to distributed systems? The help says to avoid a big number of dpConnect calls. Does it require a lot more load than to local DPs?

Our architecture consists of a redundant central system and 18 redundant distributed systems. We have a central panel with local and dist dpConnects. There are ~100 dpConnects to the dist systems, each to <10 DPs that don't change very fast, maybe every second.

Regards,
Ellen

There is no hard coded limit for the number of dpConnects in a manager, there is also no hard coded limit for dpConnects for a distributed system.
A dpConnect for a distributed system causes load in the system where the dp elements is located. The Dist Managers and the Event Manager for the other system are just gateways and forward only the messages.

100 dpConnects for about 10 dp elements should not be a problem, even if they change every second.
When doing your tests please always observe the CPU usage for the WinCC OA processes to ensure that the system is running stable without any overload condition, e.g. CPU for the Event Manager < 20% in normal operation.

Best Regards
Leopold Knipp
Senior Support Specialist