Yaskawa AC Drive Z1000 Bypass Technical Manual User Manual
Page 231

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 started to run during a current offset fault
or while coasting to a stop
Set b3-01 to 1 to enable Speed Search at Start.
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.
HOA Keypad 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.
and Tightening Torque Specifications on page 62
The rated current of the motor being used is less
than 5% of the drive rated current
Check the drive 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.
HOA Keypad 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.
and Tightening Torque Specifications on page 62
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.
HOA Keypad Display
Fault Name
nSE
Node Setup Error
A terminal assigned to the node setup function closed during run.
Cause
Possible Solution
The node setup terminal closed during run
Stop the drive when using the node setup function.
A Run command was issued while the node setup
function was active
HOA Keypad Display
Fault Name
oC
Overcurrent
Drive sensors detected an output current greater than the specified overcurrent level.
Cause
Possible Solution
The motor has been damaged due to overheating
or the motor insulation is damaged
• Check the insulation resistance.
• Replace the motor.
6.4 Fault Detection
YASKAWA ELECTRIC SIEP YAIZ1B 01D YASKAWA AC Drive – Z1000 Bypass Technical Manual
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6
Diagnostics & Troubleshooting