Mitsubishi Electric FR-V500 Series Instruction Manual page 98

Page 94
1
N
Is the torque command
unvaried?
Y
N
Has online auto tuning
been performed?
Set the online auto tuning (Pr. 95).
The torque accuracy improves.
Y
(Motor heat generation-based resistance
compensation is made.)
When the torque command
Y
is small, does the motor
rotate in the direction
opposite to the start signal?
Make torque command bias
offset calibration (Pr. 904).
N
Does the motor vibrate
Y
during acceleration/
deceleration?
Since the speed limit value increases or
decreases during acceleration/deceleration,
N
speed limit is activated.
Shorten the acceleration/deceleration time.
Is the output torque
Y
non-linear in response
to the torque command?
The excitation ratio (Pr. 854) is so low that torque is insufficient.
Increase the excitation ratio (return it to the factory setting).
Speed limit is in progress.
N
Increase the speed limit level or decrease the torque command.
At the torque command of
Y
0%, do large torque ripples
occur at the instant the
motor stops running?
In an attempt to reduce the motor speed to 0r/min,
the motor performs micro-rotation in the reverse rotation direction.
N
At that time, speed limit operation is performed and torque
control is switched to speed control.
At that time, since the factory setting of the torque limit mode
(Pr. 810) is 0 and the torque limit command is as set in
the parameter, the torque is restricted to 150%, and when an
attempt is made to reduce the speed to 0r/min, torque is generated
abruptly. Hence, the torque limit level must be decreased.
Set "1" in Pr.810 "torque limit mode" to activate torque limit.
Please contact your
sales representative.
N
Is there no influence
of noise?
Take measures to
Y
reduce noise.
N
Is the PWM carrier
frequency low?
Decrease the carrier
Y
frequency (Pr. 72).
Set the torque setting
filter (Pr. 826).
95
Troubleshooting
6