Optimising The Downloaded Schedule - rotork Mk3 Technical Manual

Foundation Fieldbus CP Option Card Technical Manual
7.4

Optimising the downloaded schedule

A downloaded schedule should consume no more than 50% of the highway's macro-cycle time.
Failure to adhere to this guideline may result in the FF card not functioning as expected.
It might be possible to increase the macro-cycle period if the 50% threshold isn't met with the DCS's
default macro-cycle time. However, if this increase in time isn't acceptable to the customer, the only
remaining option would be to manually optimise the schedule. This can be done by clicking on the
schedule objects and dragging them to the desired time position. Most DCS systems allow this sort of
manual intervention.
The basic rules of manual optimisation are:
Only one telegram can be on the highway at any one time
Within an individual FF node, only one block execution can occur at any one time.
Fig 7.6: Example of a downloaded schedule'
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