KFU 2-/4-
208
16.5.3.2 Limit Value Sources
As an alternative to limiting the output values by a fixed value, linking to an analog
input value is also possible. The analog value is limited via parameters
Minimum
reference percentage
518
and
Maximum reference percentage
519
, but does not con-
sider the
Gradient percentage ramp
477
of the reference percentage value channel.
The assignment is done with the help of the parameters
Isq limit source motor op-
eration
734
and
Isq limit source generator operation
735
for the torque-forming cur-
rent component Isq.
The sources for the torque limits can be selected via the parameters
Torque limit
source, motor op.
736
and
Torque limit source generator op.
737
.
Operation mode 736, 737
Function
101 -
Analog input MFI1A
The source is the multifunctional input 1 in an
analog
Operation mode
452.
105 -
Repetition frequency input
(F3)
The frequency signal on the repetition frequency
input corresponding to
Operation mode
496
.
110 -
Fixed limit
The selected parameter figures for limiting the
speed controller are taken into account.
Note:
The limit values and assignment to different limit value sources are data
set related in the configurations. The use of the data record change-over
demands an examination of the parameters in question.
16.5.3.3 Integral time speed synchronization
For speed synchronization and in order to increase the speed accuracy, the integrat-
ing portion of the speed control can be set via parameter
Integral time speed syn-
chronization
515
. The setup is effective in operation modes „4 – speed synchroniza-
tion DG 1“ and „5 – speed synchronization DG 2“ for parameter
Actual speed
source
766
.
Parameter
Settings
No.
Description
Min.
Max.
Fact. sett.
515 Integral time speed synch.
1 ms
60000 ms
5000 ms
16.5.4 Acceleration
Pre-Control
The acceleration pre-control is active in the speed-controlled configurations and can
be activated via parameter
Operation mode
725
.
Operation mode
725
Function
0
-
Off
The control system is not influenced.
1
-
On
The acceleration pre-control is active according to
the limit values.
The acceleration pre-control controlled parallel to the speed controller reduces the
reaction time of the drive system to a change of reference values. The minimum ac-
celeration time defines the modification speed of the reference speed value as from
which a torque necessary for acceleration of the drive is pre-controlled. The accelera-
tion of the mass is a function of the
Mech. time constant
727
of the system. The value
calculated from the increase of the reference value and the multiplication factor of the
torque required is added to the output signal of the speed controller.
