Troubleshooting - Mitsubishi Electric FR-V560 Instruction Manual

Gain adjustment for torque control
(without encoder)
3.5.3

Troubleshooting

Phenomenon
Torque control is not
exercised normally.
1
When the torque
command is small, the
2 motor rotates in the
direction opposite to the
start signal.
Normal torque control
cannot be exercised
during acceleration/
3 deceleration.
The motor vibrates.
Output torque is not linear
4 in response to the torque
command.
Related parameter reference pages
• Pr. 7 "acceleration time" (Refer to page 91.)
• Pr. 8 "deceleration time" (Refer to page 91.)
• Pr. 800 "control system selection" (Refer to page 182.)
• Pr. 802 "pre-excitation selection" (Refer to page 95.)
• Pr. 810 "torque restriction input method selection" (Refer to page 100.)
• Pr. 826 "torque setting filter 1" (Refer to page 188.)
• Pr. 904 "torque command No. 3 bias" (Refer to page 202.)
• Pr. 905 "torque command No. 3 gain" (Refer to page 202.)
For online auto tuning, refer to the Instruction Manual (basic)
Cause
(1) The phase sequence of the
motor or encoder wiring is
wrong.
(2) The control mode selection, Pr.
800, setting is improper.
(3) The speed restriction value is
not input.
(4) The torque command varies.
(5) Torque variation due to the
change in the motor
temperature.
(6) The torque command does not
match the inverter-recognized
value.
The offset calibration of the torque
command does not match.
Since the speed restriction value
changes with the setting of the
acceleration/deceleration time in
Pr. 7, Pr. 8, the speed restriction
may be activated. (When the speed
restriction is activated, torque
control cannot be exercised.)
Insufficient torque.
76
Corrective Action
(1) Check the wiring. (Refer to page 4.)
(2) Check the Pr. 800 setting. (The factory setting is
speed control)
(3) Set the speed restriction value. (If the speed
restriction value is not input, the motor will not
rotate since the speed restriction value is regarded
as 0r/min.)
(4) Check that the command device gives a correct
torque command.
Decrease the PWM carrier frequency in Pr. 72.
Increase the torque setting filter in Pr. 826.
(5) Set start time tuning of Pr. 95.
(6) Recalibrate the torque command bias and gain in
Pr. 904 and Pr. 905.
Recalibrate the torque command bias in Pr. 904.
Reduce the acceleration/deceleration time.
Alternatively, set the acceleration/deceleration time to
0. (Speed restriction during acceleration/deceleration
is speed restriction during constant speed)
Return the excitation ratio to the factory setting.