Operating Instructions

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3.5.14.4 Feedforward
Feedforward usually needs accurate process models, but in some simple cases a gain + offset type of
feedforward is enough. The feedforward part does not use any feedback measurements of the actual
controlled process value (water level in the example on page 87). Siemens feedforward control uses oth-
er measurements which are indirectly affecting the controlled process value.
3.5.14.5 Process Supervision
Process supervision is used to control that the actual value stays within predefined limits. With this func-
tion you can e.g. detect a major pipe burst and stop unnecessary flooding. See more on page 88.
Table 45: Feedforward.
Code Parameter Min Max Unit Default ID Description
P3.12.4.1 Feedforward function 1 9 1 1059 See P3.12.3.1.
P3.12.4.2
Feedforward function
gain
-1000 1000 % 100.0 1060 See P3.12.3.2.
P3.12.4.3
Feedforward 1
source selection
0 14 0 1061 See P3.12.3.3.
P3.12.4.4
Feedforward 1 mini-
mum
-200.00 200.00 % 0.00 1062 See P3.12.3.4.
P3.12.4.5
Feedforward 1 maxi-
mum
-200.00 200.00 % 100.00 1063 See P3.12.3.5.
P3.12.4.6
Feedforward 2
source selection
0 14 0 1064 See P3.12.3.6.
P3.12.4.7 Feedforward 2 min -200.00 200.00 % 0.00 1065 See P3.12.3.7.
P3.12.4.8 Feedforward 2 max -200.00 200.00 % 100.00 1066 See P3.12.3.8.
Table 46: Process Supervision.
Code Parameter Min Max Unit Default ID Description
P3.12.5.1
Enable process super-
vision
0 1 0 735
0 = Disabled
1 = Enabled
P3.12.5.2 Upper limit Varies Varies Varies Varies 736
Upper actual/process value
supervision.
P3.12.5.3 Lower limit Varies Varies Varies Varies 758
Lower actual/process value
supervision.
P3.12.5.4 Delay 0 30000 s 0 737
If the desired value is not
reached within this time a
fault or alarm is created.