Why it is not possible to load multiple schedule in FF device?

 

I suppose that if it has multiple VFDs you can, i.e. one schedule per VFD

What are you trying to achieve? Do you want some loops to execute faster than others? E.g. flow faster than temperature? There are other ways of doing that, e.g. by executing the associated blocks more than once per macrocycle. This is called subschedule and may be what you are looking for.

Take a look at chapter 4 of the yellow book "Fieldbuses for Process Control: Engineering, Operation, and Maintenance" buy online:
http://www.isa.org/fieldbuses

You may also contact me directly on the address below

Jonas Berge
SMAR
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[email protected]
www.smar.com
Learn fieldbus and Ethernet at your own pace: www.isa.org/fieldbuses
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