Models BA0001 to BA0012, 2A0001 to 2A0020, and 4A0001 to 4A0011: Setting 1.00.
Models BA0018, 2A0030 to 2A0069, and 4A0018 to 4A0038: Setting 1.50.
Normally there is no need to adjust n2-01 from the default setting. Make adjustments in the following cases:
• If hunting occurs, increase the set value in steps of 0.05 while checking the response.
• If response is low, decrease the set value in steps of 0.05 while checking the response.
n
n2-02/n2-03: AFR Time Constant 1/2
Parameter n2-02 sets the time constant normally used by AFR.
Parameter n2-03 sets the time constant during Speed Search or when during regenerative operation the actual motor slip
exceeds 50% of the rated slip.
No.
Name
Setting Range
Default
n2-02
AFR Time Constant 1
0 to 2000 ms
50 ms
n2-03
AFR Time Constant 2
0 to 2000 ms
750 ms
Note:
Parameter n2-02 cannot be set higher than n2-03 or an oPE08 error will result.
These parameters rarely need to be changed. Adjust settings only under the following conditions.
• If hunting occurs, increase n2-02. If response is low, decrease it.
• Increase the setting of n2-03 if overvoltage (ov) failures occur with high inertia loads at the end of acceleration or when the
load changes radically.
• When increasing n2-02, make sure to increase C4-02 (Torque Compensation Delay Time Constant 1) proportionally.
• When increasing n2-03, make sure to increase C4-06 (Torque Compensation Delay Time Constant 2) proportionally.
u
n3: High Slip Braking (HSB)/Overexcitation Deceleration
High Slip Braking (V/f Control)
HSB works in V/f Control only and is used to decrease the stopping time compared to normal deceleration without using
braking resistor options. HSB stops the motor by reducing the output frequency in large steps, thus producing a high slip.
Regenerative energy created from decelerating the load is dissipated in the motor windings through increased motor slip.
Because of the increased temperature of the motor windings, HSB should not be used for frequently stopping the motor. The
duty cycle should be around 5% or less.
Notes on using High Slip Braking:
• The deceleration time that has been set is ignored during HSB.
• Braking time varies based on the load inertia and motor characteristics.
• HSB must be triggered by a digital input set to H1-
oo
= 68. Once the HSB command is given, it is not possible to restart
the drive until the motor is stopped and the Run command is cycled.
Use parameters n3-01 through n3-04 for adjusting HSB.
Overexcitation Deceleration (V/f Control and Open Loop Vector)
Overexcitation deceleration increases the flux during deceleration and allows shorter deceleration time settings than with
normal deceleration without the use of a braking resistor. Enabled by setting L3-04 = 4.
Notes on Overexcitation Deceleration
• As regenerative energy is mainly dissipated as heat in the motor, the motor temperature will rise if overexcitation deceleration
is applied frequently. In such cases, make sure the motor temperature does not exceed the maximum allowable value or
consider using a braking resistor option instead.
• The drive decelerates at the active deceleration time. Make sure to set this time so that no overvoltage (ov) fault occurs.
• When a Run command is entered during overexcitation deceleration, overexcitation operation is cancelled and the drive will
reaccelerate to the specified speed.
• Do not use overexcitation deceleration in combination with a braking resistor option.
• Overexcitation deceleration cannot be used in OLV/PM control mode.
Use parameters n3-13 through n3-23 for adjusting overexcitation deceleration.
n
n3-01: High Slip Braking Deceleration Frequency Width
Sets the step width for frequency reduction during HSB. Increase this value if DC bus overvoltage (ov) occurs during HSB.
5.9 n: Special Adjustments
YASKAWA ELECTRIC SIEP C710606 18F YASKAWA AC Drive – V1000 Technical Manual
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Parameter Details