ABB S800 Product Manual page 142

S800 I/O Station Data Scanning
That will give an I/O scan cycle time of 22 ms between the FCI and its I/O modules.
This means that the DIs and DOs will be scanned every 22 ms, the AI810s and the
AO810/AO810V2 every (4*22 ms) 88ms and the AI830/AI830A every (10*22 ms)
220 ms.
Minimum I/O scan cycle time = 4 ms single FCI (CI810) with firmware 1.0 to 1.2
Minimum I/O scan cycle time = 6 ms redundant FCI (CI820) with firmware 1.3
or later.
For example, a redundant station with CI840, two AI810, one AO810/AO810V2,
two DI810, two DO820 and one AI830/AI830A will give the following I/O scan
cycle time:
Minimum I/O scan cycle time = 4 ms.
142
2 AI810 =>
1 AO810/AO810V2 => 1*1.20 ms = 1.20 ms
2 DI810 =>
2 DO810 =>
1 AI830/AI830A =>
1 CI840 =>
------------------------------------------------------
11.7 ms is not a multiple of 2, so increase of the value to the nearest multiple of
2 gives 12 ms.
That will give an I/O scan cycle time of 12 ms between the FCI and its I/O
modules. This means that the DIs, DOs, DPs and Standard Drives will be
scanned every 12 ms, the AIs and AOs every (4*12 ms) 48 ms and the
AI830/AI830A, AI835, AI843 and AI893 every (10*12 ms) 120 ms.
Section 3 Technical Data and Performance
2*3.00 ms = 6.00 ms
2*0.50 ms = 1.00 ms
2*0.50 ms = 1.00 ms
1*0.40 ms = 0.40 ms
1*2.10 ms = 2.10 ms
11.7 ms
3BSE015969-600 A