ABB ACS350 User Manual page 215

Parameters – complete descriptions
Index Name/Selection
4003 DERIVATION TIME
0.0...10.0 s
4004 PID DERIV FILTER
0.0...10.0 s
4005 ERROR VALUE INV
NO
YES
4006 UNITS
4007 UNIT SCALE
0...3
Description
Defines the derivation time for the process PID controller. Derivative action
boosts the controller output if the error value changes. The longer the
derivation time, the more the speed controller output is boosted during the
change. If the derivation time is set to zero, the controller works as a PI
controller, otherwise as a PID controller.
The derivation makes the control more responsive for disturbances.
The derivative is filtered with a 1-pole filter. Filter time constant is defined by
parameter 4004 PID DERIV FILTER.
Error
100%
0%
PID output
Gain
4001
Derivation time. If parameter value is set to zero, the derivative part of the
PID controller is disabled.
Defines the filter time constant for the derivative part of the process PID
controller. Increasing the filter time smooths the derivative and reduces
noise.
Filter time constant. If parameter value is set to zero, the derivative filter is
disabled.
Selects the relationship between the feedback signal and drive speed.
Normal: A decrease in feedback signal increases drive speed. Error = Ref -
Fbk
Inverted: A decrease in feedback signal decreases drive speed. Error = Fbk -
Ref
Selects the unit for PID controller actual values.
See parameter 3405 OUTPUT1 UNIT selections NO UNIT...Mrev.
Defines the decimal point location for the display parameter selected by
parameter 4006 UNITS.
Example PI (3.14159)
4007 value Entry
0 0003
1 0031
2 0314
3 3142
Process error value
t
D-part of controller output
t
4003
Display
3
3.1
3.14
3.142
Def, FbEq
0
1 = 0.1 s
1
1 = 0.1 s
NO
0
1
%
0...63
1
1 = 1
Actual signals and parameters
215