5.8 n: Special Adjustments
The n parameters handle a variety of specialized adjustments and functions, including Hunting Prevention.
u
n1: Hunting Prevention
Hunting Prevention keeps the drive from hunting as a result of low inertia and operating with light load.
n
n1-02: Hunting Prevention Gain Setting
Sets the gain for the Hunting Prevention Function.
No.
Name
Setting Range
Default
n1-02
Hunting Prevention Gain Setting
0.00 to 2.50
1.00
Normally, n1-02 does not need to be changed, but adjustment may help under the following conditions:
• If the motor vibrates while lightly loaded increase the gain by 0.1 until vibration ceases.
• If the motor stalls decrease the gain by 0.1 until the stalling ceases.
u
n3: Overexcitation Deceleration
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.
Use parameter n3-13 for adjusting overexcitation deceleration.
n
n3-13: Overexcitation Deceleration Gain
Applies a gain to the V/f pattern output value during overexcitation deceleration, thereby determining the level of
overexcitation. The drive returns to the normal V/f value after the motor has stopped or when it is accelerating to the
frequency reference.
No.
Name
Setting Range
Default
n3-13
Overexcitation Deceleration Gain
1.00 to 1.40
1.10
The optimum setting for n3-13 depends on the motor flux saturation characteristics.
• Increase the gain by 1.25 to 1.30 to improve the breaking power of overexcitation.
• Reduce the value when the motor slip gets too high, which can trigger overcurrent (oC), motor overload (oL1), or drive
overload (oL2) faults.
5.8 n: Special Adjustments
SIEP C710606 33A OYMC AC Drive – J1000 User Manual
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Parameter Details
