YASKAWA L1000A Quick Start Manual page 35

Problem
V/f
OLV
OLV
CLV
Motor stops shortly
(undershoot) when the
leveling speed is
reached.
CLV
CLV/PM
All
Motor speed
overshoot at
acceleration end and
undershoot when
CLV
reaching leveling
CLV/PM
speed occurs. Problem
cannot be resolved by
adjusting the speed
loop.
OLV
Motor or machine
vibrates at high speed
CLV
or top speed.
CLV/PM
V/f
OLV
OLV
CLV
Motor or machine
vibrates in the low or
medium speed range.
CLV
CLV/PM
Motor or machine
CLV
vibrates in During
CLV/PM
Position Lock.
CLV
CLV/PM
Vibrations with the
frequency equal to the
motor speed occur.
All
Oscillations when
using an analog speed All
reference.
Top speed is different
in motoring and OLV
regenerative mode.
YASKAWA ELECTRIC TOEP C710616 33G AC Drive L1000A - Quick Start Guide
Control Mode and Possible Cause
Not enough torque at low speed
Motor data incorrect
Too much slip compensation
Speed control loop responds too slow.
The inertia compensation function is not set up
correctly.
The deceleration ramp changes too quickly
when reaching the leveling speed.
Inertia is high.
Torque compensation is responding too quickly. Increase the torque compensation delay time (C4-02).
Speed control loop adjusted too hard.
Output voltage is too high.
Torque compensation is responding too quickly. Increase the torque compensation delay time (C4-02).
Output voltage is too high.
The value for the motor slip is set incorrectly.
Speed control loop adjusted too hard.
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.
Corrective Action
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 setting of C5-05 and if a third set
of speed loop settings is used or not. Refer to
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 2 , increase C2-04 if set in s.
Use the inertia compensation function. Set n5-01 to 1 and
then adjust parameters n5-02 and n5-03 as described in
Inertia Compensation (CLV and CLV/PM) on page
Decrease C5-01, then increase C5-02.
Reduce the V/f pattern settings (E1-08, E1-10).
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.
6 Fine Adjustments
Speed Loop
36.
36.
EN 35