YASKAWA HV600, Technical Reference

Page: 350 / 794

5.9 n: Special Adjustment
350 YASKAWA SIEPYAIH6B01A HV600 AC Drive Bypass Technical Reference
• When you must detect ov [DC Bus Overvoltage] during high-slip braking, set this parameter to a low value.
• If the motor current increases during high-slip braking, decrease the setting value to prevent burn damage in the
motor.
■
n3-03: HSB Dwell Time at Stop
No.
(Hex.)
Name Description
Default
(Range)
n3-03
(058A)
Expert
HSB Dwell Time at Stop Sets the dwell time, a length of time when high-slip braking is ending and during which the motor
speed decreases and runs at a stable speed. For a set length of time, the drive will hold the actual
output frequency at the minimum output frequency set in
E1-09 .
1.0 s
(0.0 - 10.0 s)
If there is too much inertia or when the motor is coasting to a stop after high-slip braking is complete, increase the
setting value. If the setting value is too low, machine inertia can cause the motor to rotate after high-slip braking is
complete.
■
n3-04: HSB Overload Time
No.
(Hex.)
Name Description
Default
(Range)
n3-04
(058B)
Expert
HSB Overload Time Sets the time used to detect oL7 [High Slip Braking Overload] , which occurs when the output
frequency does not change during high-slip braking. Usually it is not necessary to change this
parameter.
40 s
(30 - 1200 s)
If a force on the load side is rotating the motor or if there is too much load inertia connected to the motor, the drive
will detect
oL7 .
The current flowing to the motor from the load can overheat the motor and cause burn damage to the motor. Set this
parameter to prevent burn damage to the motor.
■
n3-13: OverexcitationBraking (OEB) Gain
No.
(Hex.)
Name Description
Default
(Range)
n3-13
(0531)
OverexcitationBraking
(OEB) Gain Sets the gain value that the drive multiplies by the V/f pattern output value during overexcitation
deceleration to calculate the overexcitation level. 1.10
(1.00 - 1.40)
The V/f pattern output value goes back to its usual level after the motor stops or accelerates again to the frequency
reference speed.
The best value of this parameter changes when the flux saturation characteristics of the motor change.
•
Gradually increase the value of n3-13 to 1.25 or 1.30 to increase the braking power of Overexcitation Deceleration.
If the gain is too much, the motor can have flux saturation and cause a large quantity of current to flow.
•
This can increase the deceleration time. Decrease the setting value if flux saturation causes overcurrent. If you
increase the setting value, the drive can detect
oC [Overcurrent] , oL1 [Motor Overload] , and oL2 [Drive
Overload] . Decrease the value of n3-21 [HSB Current Suppression Level] to prevent oC and oL .
•
If you use overexcitation deceleration frequently or if you use overexcitation deceleration for an extended period of
time, it can increase motor temperature. Decrease the setting value in these conditions.
•
If ov [Overvoltage] occurs, increase the deceleration time.
■
n3-21: HSB Current Suppression Level
No.
(Hex.)
Name Description
Default
(Range)
n3-21
(0579)
HSB Current Suppression
Level Sets the upper limit of the current that is suppressed at the time of overexcitation deceleration as a
percentage of the drive rated current. 100%
(0 - 150%)
If flux saturation during Overexcitation Deceleration makes the motor current become more than the value set in this
parameter, the drive will automatically decrease the overexcitation gain. If
oC [Overcurrent] , oL1 [Motor Overload] ,
or oL2 [Drive Overloaded] occur during overexcitation deceleration, decrease the setting value.
If repetitive or long overexcitation deceleration cause the motor to overheat, decrease the setting value.