Does an ModueleBus-Cluster affect the controller load?
I use an AC800PEC-Controller and several Profibus Clusters. The actual Controller load is allrady very high. Now, I would like to change one of these Clusters to a ModuleBus-Cluster (TP820). Is there a difference in the CPU-load if I use a ModuleBus-Cluster instead of a Profibus Cluster?
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If ANY modules are connected direct to the CPU using module bus then the CPU load will increase. In this case the CPU controls the scanning of the IO channels.
You can add as many modules or devices as you want to the Profibus in any (legal) configuration and the CPU load of the main controller will still be zero. All profibus communications is handled by the CI854 and written into shared memory that is read by the main CPU.