11.10 n: Special Adjustment
774 YASKAWA SIEPC71061723A YASKAWA AC Drive CR700 Technical Manual
■ n3-23: Overexcitation Braking Operation
No.
(Hex.)
Name Description
Default
(Range)
n3-23
(057B)
Overexcitation Braking
Operation
Sets the direction of motor rotation where the drive will enable overexcitation.
0
(0 - 2)
0 : Disabled
1 : Enabled Only when Rotating FWD
2 : Enabled Only when Rotating REV
Note:
When n3-23 = 1, 2, the drive enables overexcitation only in the direction of motor rotation in which a regenerative load is applied.
Increased motor loss can decrease ov [Overvoltage] faults.
◆ n4: Adv Open Loop Vector Tune
To make special adjustments for Advanced Open Loop [A1-02 = 4] (AOLV) control, note these items:
• Do Rotational Auto-Tuning first.
• When there is a load, applications must stay constant around zero speed in AOLV control. If the application will
not stay constant around zero speed, set A1-02 = 3 [Closed Loop Vector].
• The tolerance of regenerative torque at low speeds decreases in AOLV control. When regenerative torque is
necessary in the low speed range, set A1-02 = 3.
• You cannot use AOLV control in elevators or other lifting applications because there is a risk that the load could
slip.
• If you operate the drive at a frequency lower than n4-70 [Speed Command Comp @ Low Freq] (default setting:
1.00 Hz), the motor can rotate at a frequency that is approximately 1/2 of the n4-70 setting. Set E1-09
[Minimum Output Frequency] > 0 to not let the motor to rotate at a lower frequency than the n4-70 setting.
When the frequency reference ≤ E1-09, the drive output will turn OFF.
■ n4-60: Motoring Low Speed Comp Gain
No.
(Hex.)
Name Description
Default
(Range)
n4-60
(1B80)
Motoring Low Speed Comp
Gain
Sets a compensation gain to improve the control qualities for motoring loads in the low speed
range.
100.0%
(50.0 - 200.0%)
Note:
• To improve torque accuracy in the motoring direction when running at low speeds, either perform only Stationary Auto-Tuning for
Line-to-Line Resistance, or increase the setting value in 5% increments. The recommended setting is 100% to 120%.
• If the output frequency changes when you operate at low speeds, do Stationary Auto-Tuning for Line-to-Line Resistance only. If it is
not better, increase this parameter in 10% increments. The recommended setting is 50% to 100%.
■ n4-61: Low Speed Comp Frequency Level
No.
(Hex.)
Name Description
Default
(Range)
n4-61
(1B81)
Low Speed Comp
Frequency Level
Sets a frequency at which the settings n4-60 [Motoring Low Speed Comp Gain] and n4-62 [Regen
Low Speed Comp Gain] are enabled. When the output frequency < n4-61, the drive adjusts the
torque to agree with the settings for n4-60 and n4-62. Usually it is not necessary to change this
setting.
6.00 Hz
(0.50 - 12.00 Hz)
■ n4-62: Regen Low Speed Comp Gain
No.
(Hex.)
Name Description
Default
(Range)
n4-62
(1B82)
Regen Low Speed Comp
Gain
Sets a compensation gain to improve the control qualities for regenerative loads in the low speed
range.
100.0 %
(50.0 - 500.0%)
Note:
If you do not apply a regenerative load when you operate at low speeds, do stationary Auto-Tuning for Line-to-Line Resistance only. If
this does not make it better, increase the setting value in 5% increments. The recommended setting is 100% to 150%. If you set this
parameter too high, the drive will detect CF [Control Fault] at stop.