Omron VARISPEED G7 -, Instruction Manual

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Rewinding Operation
In a rewinding operation, the line (speed) and torque generated by the motor are in the opposite directions. (In
this example, we’ll assume that the line speed is positive and the torque reference input is negative.) For the
rewinding operation, the speed limit is positive and the torque reference input is negative. If the motor turns
faster than the speed limit, a negative compensation value is output from the speed limiter circuit. If the motor
is rotating in reverse, a negative compensation value is output. If the speed is 0 or is below the speed limit, a 0
compensation value is output. In this way, the output from the speed limiter is used to maintain the motor
speed between 0 and the speed limit. When the sum of the torque reference and the torque compensation out-
put by the speed limiter is the same as the actual load, the motor will stop accelerating and run at a constant
speed.
Torque Reference Adjustment
Consider the following information when adjusting the torque.
Torque Reference Delay Time: d5-02
The time constant of the primary filter in the torque reference section can be adjusted. This constant is used to
eliminate noise in the torque reference signal and adjust the responsiveness to the host controller. Increase the
setting if oscillation occurs during torque control.
Setting the Torque Compensation
Set multi-function analog input A2 or A3 to torque compensation (setting 14). When the amount of torque loss
for mechanical loss or other factor at the load is input to one of these terminals, it is added to the torque refer-
ence to compensate for the loss. The direction of torque will be as follows:
•
Positive voltage (current): Torque compensation reference for forward motor rotation (counterclockwise as
viewed from the motor output axis).
Winding Operation Rewinding Operation
Configuration
Normal Rotation
Direction
Forward Reverse Forward Reverse
Torque Reference
Polarity (TREF)
Speed Limit Polar-
ity (SLIM)
Generated Torque
X
M
Line direction
N T
Motor
X
M
Line direction
N
T
Torque
limit
Torque
limit
Speed
SLIM
0
-(d5-05)
TREF(%)
C5-01
TREF
Torque
Torque
limit
Torque
limit
Speed
SLIM
0
TREF
(d5-05)
TREF(%)
C5-01
Torque Torque
limit
Torque
limit
Speed
SLIM
0
TREF
-(d5-05)
TREF(%)
C5-01
d5-05(%)
The smaller
of these
Torque
Torque
limit
Torque
limit
Speed
SLIM
0
TREF
(d5-05)
The smaller
of these TREF(%)
C5-01
d5-05(%)
Torque