YASKAWA U1000 - Page 373

Digital Operator Display Fault Name
Cause Possible Solution
Motor insulation is damaged
• Check the insulation resistance of the motor.
• Replace the motor.
A damaged motor cable is creating a short
circuit
• Check the motor cable.
• Remove the short circuit and reapply power to the drive
• Check the resistance between the cable and the ground terminal .
• Replace the cable.
Excessive leakage current at the drive output
• Reduce the carrier frequency.
• Reduce the amount of stray capacitance.
The drive performed a current offset
adjustment while the motor was rotating
• The set value exceeds the allowable setting range while the drive automatically adjusts the current
offset. This generally only happens when attempting to restart a PM motor that is coasting to stop.
• Set b3-01 to 1 to enable Speed Search at Start.
•
Perform Speed Search 1 or 2 (H1-oo = 61 or 62) via one of the external terminals.
Hardware problem
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 Display Fault Name
LF
Output Phase Loss
• Phase loss on the output side of the drive.
• Setting L8-07 to 1 or 2 enables Phase Loss Detection.
Cause Possible Solution
The output cable is disconnected
• Check for wiring errors and properly connect the output cable.
• Correct the wiring.
The motor winding is damaged
• Check the resistance between motor lines.
• Replace the motor if the winding is damaged.
The output terminal is loose
• Apply the tightening torque specified in this manual to fasten the terminals. Refer to Main Circuit
Wire Gauges and Tightening Torque on page 98 for details.
The rated current of the motor being used is
less than 5% of the drive rated current
Check the drive selection and motor capacities.
An output transistor 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.
A single-phase motor is being used The drive cannot operate a single phase motor.
Digital Operator Display Fault Name
LF2
Output Current Imbalance
One or more of the phases in the output current are lost.
Cause Possible Solution
Phase loss has occurred on the output side of
the drive
• Check for faulty wiring or poor connections on the output side of the drive.
• Correct the wiring.
Terminal wires are loose on the output side of
the drive
Apply the tightening torque specified in this manual to fasten the terminals. Refer to Main Circuit Wire
Gauges and Tightening Torque on page 98 for details.
The output 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.
Motor impedance or motor phases are uneven
• Measure the line-to-line resistance for each motor phase. Ensure all values match.
• Replace the motor.
6.4 Fault Detection
YASKAWA ELECTRIC SIEP C710636 04D U1000 Industrial MATRIX Drive Technical Manual
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Troubleshooting