Is it possible to use the CI854/CI840 (Profibus communication) in AC800MHi(High integrity)?
Good question !
PM865, SM811, AI880... could be used in HI controller, SIL2/SIL3.
For CI854, CI840 I can find "Used together with HI Controller" - that means for me they could be connected to HI controller, but I/O modules in this clusters could NOT be failsafe in this case.
So I think NO failsafe clusters trough Profibus.
Please check the manual:
3BNP004865-513 - AC800M High Intergrity Safety Manual (some items from it below):
The AC 800M HI does not require any redundancy for safety integrity reasons
Note that the certified I/O modules are supported by ModuleBus only.
Other available communication interfaces are certified interference free, i.e. they
can be used in the AC 800M HI and the data communicated on them can be used in
both SIL and non-SIL Applications, but only for non safety critical functions