ABB S800 I/O Manual page 50

CI840 Configuration Rules
It is not allowed to physically install more than 12 single MTUs and/or S800L
modules in a single cluster. It is also not allowed to physically install more than 6
redundant MTUs in a redundant cluster.
Due to the PROFIBUS-DPV1 specification it is not possible to always connect 24
I/O modules to one FCI. The reason is that the S800 I/O system includes more data
and user parameters than PROFIBUS-DPV1 can handle.
number of I/O modules that can be connected to one CI840.
50
Table 12. Maximum Number of Modules on CI840
Module Type
AI801, AI810, AI815,
AI830, AI830A, AI835,
AI835A, AI890, AI893,
AI895
AI820, AI825
AI843
AI845
AO801, AO810, AO815,
AO810V2, AO845,
AO845A, AO890, AO895
AO820
DI801, DI802, DI803,
DI810, DI811, DI820,
(1)
DI821, DI825 , DI890
DI818
DI828
(1) (1)
DI830 , DI831
DI840
(1)
DI885
Section 3 Configuration
Table 12
Number of Modules
14 (11)
24 (22)
11 (9)
14 (11)
7 (5)
14 (11)
24 (24)
24 (24)
24 (24)
15 (15)
16 (16)
22 (21)
shows maximum
3BSE020926-600