YASKAWA L1000A Technical Manual page 155

Problem
V/f and OLV Not enough torque at low speed.
OLV and
CLV
Motor stops shortly (under-
shoot) when the leveling
speed is reached.
CLV
CLV/PM
All
Motor speed overshoot at
acceleration end and under-
shoot when reaching leveling CLV
speed occurs. Problem can- CLV/PM
not be resolved by adjusting
the speed loop.
OLV
Motor or machine vibrates at
CLV
high speed or top speed.
CLV/PM
V/f
OLV
OLV
Motor or machine vibrates in
CLV
the low or medium speed
range.
CLV
CLV/PM
Motor or machine vibrates in CLV
During Position Lock. CLV/PM
CLV
CLV/PM
Vibrations with the fre-
quency equal to the motor
speed occur.
All
Oscillations when using an
All
analog speed reference.
Top speed is different in
motoring and regenerative OLV
mode.
Speed reference and motor
speed do not match when
All
using an analog reference
signal.
All
Acceleration is longer than
set to C1- parameters.
V/f and OLV
OLV, CLV
CLV/PM
All
Motor speed does not match
the speed reference at con- V/f
stant speed.
OLV, CLV
CLV/PM
High frequency acoustic
All
noise from the motor.
YASKAWA ELECTRIC SIEP C710616 38F YASKAWA AC Drive - L1000A Technical Manual
Control Mode and Possible Cause
Motor data incorrect.
Too much slip compensation.
Speed control loop responds too slow.
The inertia compensation function is not set up correctly.
The deceleration rate changes too quickly when reaching
leveling speed.
Inertia is high.
Torque compensation responds too quickly.
Speed control loop adjusted too hard.
Output voltage is too high.
Torque compensation is responding too quickly.
Output voltage is too high.
The value for the motor slip is set incorrectly.
Speed control loop adjusted with too much gain.
The Position Lock control loop does not respond fast enough.
The speed control is not responding quickly enough when the
brake is released.
Encoder vibrates.
Mechanical problems.
Rotational parts (motor armature, handwheel, brake disk/
drum) are not properly balanced.
The analog reference value is not stable or the signal is noisy.
Slip Compensation during Regenerative operation is switched
off.
The drives analog input is not set according to the signal level
of the controller speed reference output signal.
The load is too high.
The load is too high and the current/torque exceeds the stall
prevention level.
The load is too high and the torque exceeds the drives torque
limits.
The load is too high.
The load is too high and the current/torque exceeds the stall
prevention level.
The load is too high and the torque exceeds the torque limits.
The carrier frequency is too low.
4.7 Setup Troubleshooting and Possible Solutions
Increase the Minimum and Middle Voltage Levels for the V/f pattern voltage
(E1-10 and E1-08 respectively). Make sure that the Starting and Leveling
Current does not rise too high.
Adjust the motor data (E2-), especially the motor slip (E2-02) and
no-load current values (E2-03), or perform Auto-Tuning.
Increase the Speed Control Gain and reduce the Speed Control Integral Time
used for Low Speed at Stop. The parameters to be changed depend on the set-
ting of C5-05 and whether a third set of speed loop settings is used. Refer to
Speed Loop Adjustments (CLV and CLV/PM) on page
If the Inertia Compensation Function is used (n5-01 = 1) make sure the values
in n5-02 and n5-03 are correct.
Decrease the Jerk at the End of Deceleration. Decrease C2-04 if set in m/s
increase C2-04 if set in s.
Use the Inertia Compensation Function. Set n5-01 to 1 and then adjust param-
eters n5-02 and n5-03 as described in
PM) on page 133.
Increase the Torque Compensation Delay Time (C4-02).
Decrease C5-01, then increase C5-02.
Reduce the V/f Pattern settings (E1-08, E1-10).
Increase the Torque Compensation Delay Time (C4-02).
Reduce the V/f Pattern settings (E1-08, E1-10).
Check the Motor Slip value in parameter E2-02. Increase or decrease it in
steps of 0.2 Hz.
• Decrease C5-01 and then increase C5-02 if the problem occurs at speed
higher than C5-07.
• Decrease C5-03 and then increase C5-04 if the problem occurs at speed
lower than C5-07.
• Decrease C5-13 and then increase C5-14 if the problem occurs at speed
lower than C5-07 but only during deceleration.
• If vibration occurs at During Position Lock at start, first decrease S3-02. If
decreasing S3-02 does not resolve the problem, decrease S3-01.
• Decrease S3-03 if vibration occurs During Position Lock at stop.
Decrease C5-19 and then increase C5-20.
Check the encoder mounting and the alignment of encoder and motor shaft.
Check bearings and gearbox.
Properly balance rotating parts.
• Check the analog signal line connection. Use shielded twisted pair cables.
• Apply a filter to the analog input signal by setting parameter H3-13.
Make sure C3-04 is set properly and set parameter C3-05 to 0.
Check the gain and bias settings for the analog input that is used to set the
speed reference. Check parameters H3-03 and H3-04 for input A1, check
parameters H3-11 and H3-12 for input A2.
• Check if the acceleration rate set is not too high (acceleration time is too
short).
• Make sure the drive rated current is enough to fulfill the application
requirements.
• Make sure the load is not seized, car guide lubrication is ok, etc.
Check if the Stall Prevention Level at Acceleration in L3-03 is not set too
small.
Check it the Torque Limit parameters L7- are not set too low.
Make sure the drive rated current is enough to fulfill the application require-
ments.
Check if the Stall Prevention Level During Run in L3-06 is not set too low.
Check it the Torque Limit parameters L7- are not set too low.
Increase the Carrier Frequency in parameter C6-03. If the carrier frequency is
set higher than the default setting, a current derating must be considered.
Corrective Action
133.
Inertia Compensation (CLV and CLV/
,
2
4
155