11 Inspection, Maintenance, and Troubleshooting
11-42
11.5
Troubleshooting Malfunction Based on Operation and
Conditions of the Motor
Troubleshooting for the malfunctions based on the operation and conditions of the motor is provided in this
section.
Be sure to turn OFF the servo system before troubleshooting items shown in bold lines in the table.
Problem
Probable Cause
Investigative Actions
Corrective Actions
Motor Does Not
Start
The control power supply is not
ON.
Check voltage between control
power terminals.
Correct the wiring.
The main circuit power supply is
not ON.
Check the voltage between main
circuit power terminals.
Correct the wiring.
Wiring of I/O signal connector CN1
faulty or disconnected.
Check if the connector CN1 is prop-
erly inserted and connected.
Correct the connector CN1 connec-
tion.
Motor or encoder wiring discon-
nected.
Check the wiring.
Correct the wiring.
Overloaded
Run under no load and check the
load status.
Reduce load or replace with larger
capacity motor.
Settings for the input signal selec-
tions (Pn50A and Pn50B) is incor-
rect.
Check the settings for parameters
Pn50A and Pn50B.
Correct the settings for parameter
Pn50A and Pn50B.
Motor type differs from parameter
setting (Pn01E.0).
Check the settings for parameter
Pn01E.0.
Set parameter Pn01E.0 to the motor
type being used.
Encoder type differs from parame-
ter setting (Pn01F.0).
Check the settings for parameter
Pn01F.0.
Set parameter Pn01F.0 to the
encoder type being used.
SV_ON command (Enable opera-
tion) is not sent.
Check the command sent from the
host controller.
Send the SV_ON command (Enable
operation).
The forward run prohibited (P-OT)
and reverse run prohibited (N-OT)
input signals are turned OFF.
Check P-OT or N-OT input signal.
Turn P-OT or N-OT input signal
ON.
The safety input signal (/HWBB1 or
/HWBB2) remains OFF.
Check the /HWBB1 and /HWBB2
input signal.
Set the /HWBB1 and /HWBB2
input signal to ON.
SERVOPACK failure
−
Replace the SERVOPACK.
Motor Moves
Instantaneously,
and then Stops
Servomotor wiring is incorrect.
Check the motor wiring.
Correct the wiring.
Encoder wiring is incorrect.
Check the encoder wiring.
Correct the wiring.
Motor Speed
Unstable
Wiring connection to motor is
defective.
Check connections of power line
(phases U, V, and W) and encoder
connectors.
Tighten any loose terminals or con-
nectors and correct the wiring.
Motor Rotates
Without
Reference Input
SERVOPACK failure
−
Replace the SERVOPACK.
Dynamic Brake
Does Not Operate
Improper Pn001.0 setting
Check the setting for parameter
Pn001.0.
Correct the setting for parameter
Pn001.0.
Improper Pn01E.1 setting
Check the setting for parameter
Pn01E.1.
Correct the setting for parameter
Pn01E.1.
Improper Pn601 setting
Check the setting for parameter
Pn601.
Correct the setting for parameter
Pn601.
External DB circuit fault
Check the wiring and components
for external DB circuit.
Correct the wiring for external DB
circuit, or replace the components.
DB resistor disconnected
Check if excessive moment of iner-
tia, motor overspeed, or DB fre-
quently activated occurred.
Replace the SERVOPACK, and
reduce the load.
DB drive circuit fault
−
There is a defective component in
the DB circuit. Replace the SER-
VOPACK.
