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Digital Operator Display
Fault Name
A damaged motor cable is creating a short
circuit.
• Check the motor cable.
• Remove the short circuit and turn the power back on.
• Check the resistance between the cable and the ground terminal .
• Replace the cable.
The leakage current at the drive output is too
high.
• Reduce the carrier frequency.
• Reduce the amount of stray capacitance.
The drive started to run during Current Offset
Fault or while coasting to a stop.
• The value set exceeds the allowable setting range while the drive automatically adjusts the current offset
(this happens only attempting to restart a PM motor that is coasting to stop).
• Enable Speed Search at start (b3-01 = 1).
• Perform Speed Search 1 or 2 (H1-
oo
= 61 or 62) via one of the external terminals.
Note:
Speed Search 1 and 2 are the same when using OLV/PM control mode.
Hardware problem.
• Replace the drive.
Digital Operator Display
Fault Name
LF
Output Phase Loss
• Phase loss on the output side of the drive.
• Phase Loss Detection is enabled when L8-07 is set to 1 or 2.
Cause
Possible Solution
The output cable is disconnected.
• Check for wiring errors and ensure the output cable is connected properly.
• 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.
Torque Specifications on page 66
.
The motor being used is less than 5% of the
drive rated current.
Check the drive and motor capacities.
An output transistor is damaged.
Replace the drive.
A single-phase motor is being used.
The drive being used 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 is 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 on the output side of the drive
are loose.
Apply the tightening torque specified in this manual to fasten the terminals.
Torque Specifications on page 66
No signal displays from the gate driver board. Replace the drive. Contact Yaskawa for assistance.
Motor impedance or motor phases are uneven.
• Measure the line-to-line resistance for each motor phase. Ensure all values are the same.
• Replace the motor. Contact Yaskawa for assistance.
Digital Operator 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.
• Check whether a Run command was accidentally entered via the terminals or from a comm. option
unit.
• Turn off the Run command when using the node setup function.
A Run command was issued while the node
setup function was active.
Digital Operator Display
Fault Name
oC
Overcurrent
Drive sensors have 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
272
YASKAWA ELECTRIC SIEP C710606 18F YASKAWA AC Drive – V1000 Technical Manual