ABB i-bus KNX AC/S 1.x.1 Series Product Manual page 130

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ABB i-bus KNX
Parameters
Function
Schematic diagram of controller:
Algorithms:
•
ControlValue = ProportionalValue + IntegralValue + DerivativeValue
•
ProportionalValue = Deviation x ProportionalCoefficient
•
IntegralValue = IntegralValue Old + Deviation x CycleTime / IntegralTime
•
DervativeValue = (Deviation - Deviation Old) / CycleTime x DerivativeTime
The controller calculates a new output value in the cycle time for the logic calculation (see Settings)
(usually every 200 ms). The output sends on value change.
If the ControlValue exceeds the Upper limit or Lower limit (see parameters), the values are limited
accordingly and the IntegralValue is reduced.
If the Reset input = 1: the integral value is set to 0.
Exceptions
For parameter inputs (Proportional coefficient, Integral time, Derivative time) not connected, the function
element uses the value 0.
Bus voltage failure, download and restart
The integral value is saved. The value is restored on restart.
130 2CDC508198D0211 Rev. A | AC/S 1.x.1