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Speed control by Real sensorless vector
control, vector control
114
4.4.6 Torque biases (Pr. 840 to Pr. 848)
(1) Block diagram
This function accelerates the rise of the torque at a start. Adjust the torque at a motor start using the contact
signals or analog signals .
Parameter
Number
Name Initial Value Setting Range Description
840 Torque bias selection
9999
0
Set the torque bias amount with the contact signal
(X42, X43) using Pr. 841 to Pr. 843.
1
Set the terminal 1-based torque bias amount as
desired in C16 to C19 . (in the case a cage goes up
when a motor runs reversely)
2
Set the terminal 1-based torque bias amount as
desired in C16 to C19 . (in the case a cage goes up
when a motor runs forward)
3
The terminal 1-based torque bias amount can be
set automatically in C16 to C19, Pr. 846 according
to the load.
9999 Without torque bias, rated torque 100%
841 Torque bias 1
9999
600 to 999% Negative torque bias amount (-400% to -1%)
842 Torque bias 2
1000 to 1400% Positive torque bias amount (0% to 400%)
843 Torque bias 3 9999 Without torque bias setting
844 Torque bias filter
9999
0 to 5s Time until torque rises.
9999 Same operation as when 0s is set.
845
Torque bias operation
time
9999
0 to 5s
Time for maintaining torque equivalent to the
torque bias amount.
9999 Same operation as when 0s is set.
846
Torque bias balance
compensation
9999
0 to 10V Set the voltage under balanced load.
9999 Same operation as when 0V is set.
847
Fall-time torque bias
terminal 1 bias
9999
0 to 400% Set the bias value of the torque command.
9999 Same as at a rise time (C16, C17 (Pr. 919)).
848
Fall-time torque bias
terminal 1 gain
9999
0 to 400% Set the gain value of the torque command.
9999 Same as at a rise time (C18, C19 (Pr. 920)).
The above parameters can be set when the FR-A7AP/FR-A7AL (option) is mounted.
Vector
Vector
Internal parameters
[
Pr. 840 = 0]
IM
CW
-
-
+
X42
X43
+
+
+
0
Integration cleared to 0
+
+
Speed command
Torque bias selection 1
Torque bias selection 2
Speed command
[Pr. 841]
[Pr. 842]
[Pr. 843]
Speed
control
P gain
Speed
control
integral time
Torque
control
[Pr. 840
= 1
,
2
,
3]
C16, C17
[Pr. 919]
C18, C19
[Pr. 920]
[Pr. 846]
[Pr. 845]
[Pr. 826]
Torque setting filter 1
Terminal 1
Encoder
Cage
Load
detector
CW Cage
CW > Cage