YASKAWA CR700

13 Troubleshooting
YASKAWA TOEPC71061723A YASKAWA AC Drive CR700 Quick Start Guide 65
Code Name Causes Possible Solutions
The output current is fluctuating due to input power
supply phase loss.
• Examine for wiring errors or disconnected wires in main
circuit drive input power, and repair problems.
• Make sure that there is no phase loss, and repair problems.
oL3 Overtorque Detection 1
A fault occurred on the machine.
Example: The machine is locked.
Examine the machine and remove the cause of the fault.
oL4 Overtorque Detection 2
A fault occurred on the machine.
Example: The machine is locked.
Examine the machine and remove the cause of the fault.
oL5 Overload Detection (oL5)
A fault occurred on the machine.
Example: Overload occurred.
Examine the machine and remove the cause of the fault.
oL6 Light-load Accel 2 Fault (oL6)
The setting for hold level and fault detection level
of Light-load 2 functions are not appropriate.
Adjust S4-10 [L-L 2 Motoring Hold Level], S4-12 [L-L 2 Regen
Hold Level], and S4-15 [L-L 2 Fault Detection Level] settings.
oPr Keypad Connection Fault
The keypad is not securely connected to the
connector on the drive.
Examine the connection between the keypad and the drive.
oS Overspeed
Overshoot is occurring. Reduce C5-01 [ASR Proportional Gain 1] and increase C5-02
[ASR Integral Time 1].
ov Overvoltage
Deceleration time is too short and regenerative
energy is flowing from the motor into the drive.
• Set L3-04 = 1 [Stall Prevention during Decel = General
Purpose] to enable stall prevention.
• Increase the value set in C1-02, C1-04, C1-06, or C1-08
[Deceleration Time].
• Connect a dynamic braking option to the drive.
• Perform Deceleration Rate Auto-Tuning.
The acceleration time is too short. • Examine if sudden drive acceleration causes an overvoltage
fault.
• Increase the value set in C1-01, C1-03, C1-05, or C1-07
[Acceleration Time].
• Increase the value set in C2-02 [S-Curve Time @ End of
Accel].
The braking load is too large. Connect a dynamic braking option to the drive.
Surge voltages are entered into input power supply. Connect a DC reactor to the drive.
Note:
Within the same power supply system, turning phase
advancing capacitors on and off, and operating thyristor
converters may apply surge voltages and cause the input
voltage to rise abnormally.
The drive output cable or motor is shorted to ground
(the current short to ground is charging the main
circuit capacitor of the drive through the power
supply).
1. Examine the motor main circuit cable, terminals, and motor
terminal box, and then remove ground faults.
2. Re-energize the drive.
The power supply voltage is too high. Decrease the power supply voltage so that it matches the drive
rated voltage.
The braking resistor or braking resistor unit wiring
is incorrect.
Correct wiring errors in the connection to the braking resistor or
braking resistor unit.
The encoder cable is incorrectly wired or
disconnected.
Examine for wiring errors or disconnected wires in the encoder
cable, and repair problems.
Noise interference along the encoder cable. Separate the encoder cable from the source of the noise such as
the drive output line.
A drive malfunction occurred due to electrical
interference.
• Examine the control circuit lines, main circuit lines, and
ground wiring, and decrease the effects of electrical
interference.
• Make sure that a magnetic contactor is not the source of the
electrical interference, then use a Surge Protective Device if
necessary.
The load inertia is not set correctly. • Examine the load inertia settings when using Stall Prevention
during Deceleration function.
• Adjust L3-25 [Load Inertia Ratio] settings in accordance with
the machine.
Motor hunting occurs. • Adjust the parameters that control hunting.
• Adjust n1-02 [Hunting Prevention Gain Setting] settings.
• Adjust n2-02 [Automatic Freq Regulator Time 1] and n2-03
[Automatic Freq Regulator Time 2] settings.
PF Input Phase Loss
There is a phase loss in the drive input power. Correct errors with the wiring for main circuit drive input power.
There is loose wiring in the drive input power
terminals.
Tighten the terminal screws to the correct tightening torque.
The drive input power voltage is changing too
much.
• Examine the input power for problems.
• Make the drive input power stable.
• If the input power supply is good, examine the magnetic
contactor on the main circuit side for problems.
There is unsatisfactory balance between voltage
phases.
• Examine the input power for problems.
• Make the drive input power stable.
• Set L8-05 = 0 [Input Phase Loss Protection Sel = Disabled].
EN