ABB ACS350 Series, Руководство пользователя

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