YASKAWA L1000H - Page 39

8 Troubleshooting
YASKAWA Europe TOEP C710616 92D AC Drive L1000H Quick Start Guide EN 39
Overcurrent
(oC)

• Short-circuit or ground fault on the drive output side.
• The drive is damaged.
• The load is too heavy.
• The acceleration or deceleration ramps are too short.
• The overcurrent level has exceeded the value set to
L8-27. (PM control modes)
• Incorrect motor data or V/f pattern settings.
• The motor contactor was switched while the drive was
running.
• Check the output wiring and the motor for short
circuits or broken insulation. Replace the broken
parts.
• Check the machine for damages (gears, etc.) and
repair any broken parts.
• Check the drive output side short circuit for broken
output transistor.
 B1 and U/V/W
 – (negative) and U/V/W
Contact your YASKAWA representative or nearest
YASKAWA sales office.
• Make sure the brake fully opens.
• Check accel/decel settings in C1- and C2-.
• Correct the value set to overcurrent detection gain
(L8-27).
• Check V/f pattern settings in E1- (E3- for
motor 2).
• Check the output contactor sequence.
Heatsink Overheat
(oH) or (oH1)

• Surrounding temperature is too high.
• The cooling fan has stopped.
• The heatsink is dirty.
• The airflow to the heatsink is restricted.
• Check the surrounding temperature and install
cooling devices if necessary.
• Check the drive cooling fan.
• Clean the heatsink.
• Check the airflow around the heatsink.
Motor Overload
(oL1)

• The motor load is too heavy.
• Acceleration and deceleration cycle times are too
short.
• Value set for the motor rated current is incorrect.
• Check the elevator mechanics.
• Check the sequence.
• Check the rated current setting.
Drive Overload
(oL2)

• The load is too heavy.
• The drive is too small.
• Too much torque at low speed.
• Check the load.
• Make sure that the drive is big enough to handle the
load.
• The overload capability is reduced at low speeds.
Reduce the load or increase the drive size.
DC Bus
Overvoltage
(ov)

• DC bus voltage rose too high.
• Braking transistor is too small.
• Braking chopper or resistor is broken.
• Unstable motor control in OLV.
• Input voltage is too high.
• Make sure the braking resistor and braking chopper
are working correctly.
• Check motor parameter settings and adjust torque and
slip compensation as needed.
• Make sure that the power supply voltage meets the
drives specifications.
Input Phase Loss
(PF)

• Input voltage drop or phase imbalance.
• One of the input phases is lost.
• Drive input wire are loose.
• Check the motor wiring.
• Make sure all terminal screws in the drive and motor
are properly tightened.
• Check the motor and drive capacity.
Braking Resistor
Fault
(rF)

• The proper braking resistor option has not been
installed.
• Regenerative converter, regenerative unit, or braking
unit is being used.
• Select the braking resistor option so that fits to the
drives braking transistor specification.
• Disable the braking transistor protection selection (set
L8-55 to 1).
Internal Braking
Transistor Fault
(rr)

The internal braking transistor is defective or the
braking resistor is connected wrong.
• Make sure the braking resistor is connected correctly.
• Cycle the power supply.
• Replace the drive if the fault reoccurs.
IGBT Short
Circuit
(SC)

• The motor has been damaged due to overheating or
the motor insulation is damaged.
• One of the motor cables has shorted out or there is a
grounding problem.
• The drive is damaged.
• Check the insulation resistance.
• Check the wiring to the motor. Turn the power supply
off and then on again to check operation.
• Check the drive output side short circuit for broken
output transistor.
 B1 and U/V/W
 – (negative) and U/V/W
Contact your YASKAWA representative or nearest
YASKAWA sales office.
Safety Circuit
Fault
(SCF)
 The safety circuit is damaged.
If the problem continues, replace the control board or
the entire drive. Contact YASKAWA or a YASKAWA
representative for instructions on replacing the control
board.
Digital Operator AL FLT Possible Cause Corrective Action