YASKAWA ELECTRIC
SIEP C710617 19A YASKAWA AC Drive CR700 Technical Manual
731
•
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
.
•
Regular use of overexcitation deceleration or extended periods of overexcitation deceleration can increase
internal motor temperatures. Decrease the setting value in these conditions.
•
If
ov [Overvoltage]
occurs, increase the deceleration time.
n3-14: OEB High Frequency Injection
No.
(Hex.)
Name
Description
Default
(Range)
n3-14
(0532)
Expert
OEB High Frequency
Injection
Sets the function that injects harmonic signals during overexcitation
deceleration.
0
(0, 1)
Enable this parameter to set a shorter deceleration time.
Note:
•
If you frequently use overexcitation deceleration on a motor, the motor loss will increase the risk of burn damage.
•
When you set this parameter to
1
, the motor can make a loud excitation sound during overexcitation deceleration. If the excitation
sound is unwanted, set this parameter to
0
to disable the function.
0 : Disabled
1 : Enabled
The drive injects harmonic signals at the time of overexcitation deceleration. You can decrease the deceleration
time because motor loss increases.
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, where the drive rated current = 100% value.
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.
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
The following explains how to make special adjustments for
Advanced Open Loop Vector [A1-02 = 4]
.
•
First, perform Rotational Auto-Tuning.
•
Operation that fluctuates around zero speed cannot be carried out when there is a load. For applications of this
sort, set
A1-02 = 3 [Open Loop Vector]
.
V/f
CL-V/f
OLV
CLV
AOLV
V/f
CL-V/f
OLV
CLV
AOLV
V/f
CL-V/f
OLV
CLV
AOLV
