
Chapter
5
Troubleshooting
37
gain (A3-05) and decreasing the integral time (A3-06) in the prerequisite of
no motor oscillation.
Solutions to large overshoot:
1. Decreasing the integral time of the hydraulic loop and increasing
differential time of the hydraulic loop will restrain overshoot better.
2. On the condition of satisfying the pressure rise response, decrease the
value of A3-25 (S curve inflexion filter time) appropriately.
Fault Symptom
The motor noise and vibration are large.
Fault Principle
Electrical control or mechanical connection problem
Fault Cause
Solution
Carrier frequency set
improperly
Increase the value of F0-15 (Carrier frequency) but the setting must be
within 5 kHz.
Coupler connection
improper
Check whether the coupler connection becomes loose or whether the
coupler is worn. If the coupler is damaged, replace it.
Bearing damaged
Disconnect the hydraulic pump from the motor and separate the coupler.
Rotate the motor manually. If there is uneven resistance or noise during
rotation, it indicates that the motor bearing is damaged. You can also
increase the motor rotational speed to the rated rotational speed gradually
and check whether there is abnormal noise.
Hydraulic pump
damaged
If the coupler is not damaged, check whether the hydraulic pump is
damaged. Set the holding pressure to 175 kgf and observe the motor
rotational speed. If the rotational speed is over 200 RPM, it indicates that
the hydraulic pump may be faulty. Then disconnect the hydraulic pump from
the motor, and check the motor first. If the motor is not damaged, you can
judge that the hydraulic pump is faulty.
Fault Symptom
"HC" is displayed upon power-on.
Fault Principle
Power supply fault
Fault Cause
Solution
External short-circuit
Disconnect all signal cables and the power supply cable of the cooling fan of
the servo drive. Power off the servo drive, ensure that there is no display,
and then power on the servo drive again, if the display is normal, it indicates
that short-circuit occurs on external signal cables and the power supply
cable of the cooling fan. If "HC" is still displayed, go to the next step.
PG card
short-circuited
If "HC" is still displayed after re-power-on, replace the PG card. If the fault
persists after replacement, contact the IMM manufacturer if the servo drive
is below 30 kW and go to the next step if the servo drive is above 37 kW.
Control board faulty
If the signal cables are normal, check the control board. Replace the control
board. Power off the servo drive, ensure that there is no display, and then
power on the servo drive again. If the display is normal, it indicates that the
control board is faulty. In this case, contact the IMM manufacturer.
Power supply to drive For the servo drive of 37 kW above, replace the drive board. Power off the