Starting Torque Compensation Function (For Spec:f); Starting Torque Compensation Function (C4-03 To C4-05); Time Chart For Startingtorque Frequency - YASKAWA VARISPEED-616G5 Instruction Manual

7.1.5 Starting Torque Compensation Function (for SPEC:F)

Starting Torque Compensation Function (C4-03 to C4-05)

J
Speed command input (terminal 13)
Forward (Reverse) command input
(terminal 1(2))
Time constant: C4-05
Torque compensation volume
E1-09
Output frequency
*
If the limited output voltage operation is disabled and output voltage becomes saturated, slip com-
D
pensation is automatically disabled to prevent instability.
The output current does not change when the slip compensation is disabled, however precise speed
control is no longer possible. Enable limited output voltage operation if precise speed control is re-
quired.
If the limited output voltage operation is enabled, the magnetic flux current of the motor is automatical-
D
ly controlled, and the output voltage command itself is limited, which maintains precise speed control.
Check the Inverter current margins as the output current will be maximum 10% higher (with a rated
load) than when limited output voltage operation is disabled.
Note 1.C3-06 does not need to be changed if the Unit is used only at medium or low speeds, or
when the power supply voltage is 10% or more higher than the rated voltage of the motor,
or when speed control precision in the high-speed region is not required.
2. When the power supply voltage is too low for the rated motor voltage, speed control will
not be precise even if limited output voltage operation is enabled.
Starting torque compensation can be input to speed up the torque command at starting with open-loop vec-
tor control.
This function is effective for machinery with large friction loads, cranes, and other applications where
starting torque is required. However, this compensation only applies at startup, in contrast to Flux vector
control.
User User
Constant Name
Number
Starting torque com-
C4-03
pensation value
(forward direction)
Starting torque com-
C4-04 pensation value
(reverse direction)
Constant for starting
C4-05
torque compensation
Closed
Open
Time constant:
C4-02
C4-05 × 4
The lower limit of Inverter's torque value is determined by the above torque
compensation value.
Fig 7.4

Time Chart for StartingTorque Frequency

When this function is used, set the starting torque value to the friction load value for ordinary machin-
D
ery, and to the load for cranes and other lifting devices.
Friction load: Set the friction load for both C4-03 and C4-04.
•
Lifting devices: Set the load for the motor side only (hoist). Do not use this function for lifting de-
•
vices with counterweights as a shock will be generated if there is a regenerative load.
Compensation can be set only for the motoring side, for both the forward and reverse directions. It can-
D
not be set for the regenerative side.
Starting torque compensation is disabled when switching between forward and reverse after conduct-
D
ing a speed search.
Starting torque compensation is always disabled when the second motor is used.
D
Change g
during during Setting Setting Unit Factory Factory
Opera- Range
tion
0.1
0.0 to 200.0
×
%
−200.0 to 0.1
×
0.0 %
1
0 to 200
×
ms
C4-03 (forward)
C4-04 (reverse, negative polarity)
7 - 9
7.1 Open-loop Vector Control
Valid Access Levels
Open
V/f V/f with
Setting
Loop
Control PG
Vector
A
0.0
× ×
0.0 A
× ×
A
10
× ×
The larger between b2-01 and E1-09
Flux
Vector
×
×
×
7