Omron R88D-KN series User Manual page 393

Symptom
The servo locks but the
motor does not operate.
The motor operates
momentarily, but then it
does not operate after
that.
The motor operates
without a command.
G5 Series AC Servo Drives With Built-in EtherCAT Communications, Linear Motor Type
Probable cause
The host controller does not
give a command.
The Servo Drive received a
command but it is not
accepted.
It is hard to determine if the
motor is rotating
The brake is operating.
The force limits set in the
Positive torque limit value
(60E0 hex) and the
Negative torque limit value
(60E1 hex) are too small.
The Positive or Negative
Drive Prohibition Input
(POT or NOT) is OFF.
The control mode does not
conform to the command.
The motor power cable is
wired incorrectly.
The external encoder cable
is wired incorrectly.
Power is not supplied.
The Servo Drive has broken
down.
The position commands
given are too little.
The motor power cable is
wired incorrectly.
The external encoder cable
is wired incorrectly.
There are inputs of small
values in speed control
mode.
The Servo Drive has broken
down.
12 Troubleshooting and Maintenance
Items to check
For a position command, check
to see if the speed and position
are set to 0.
Check to see if the Servo Drive
retains the object value for two
communications cycles or more
in Profile position mode (pp).
Check to see it the speed
command given by the host
controller is too small.
Check the brake interlock
output (BKIR) signal and the
+24 VDC power supply.
Check to see if the force limits
in objects 60E0 hex and
60E1 hex are set to a value
close to 0.
Check the ON/OFF state of the
POT and NOT signals from the
CX-Drive.
Check the set value of the
Control Mode Selection
(3001 hex).
Check the wiring.
Check the power supply and
the 7-segment display.
Check the voltage between the
power terminals.

Check the position data and the
electronic gear ratio at the host
controller.
Check the wiring of the motor
power cable's phases U, V, and
W.
Check the external encoder
cable's wiring.
Check if there is an input in
speed control mode.

Measures
Enter position and speed data.
Start the motor.
Set the Servo Drive so that it
retains the object value for two
communications cycles or
more.
Check the speed command
from the host controller.
Check to see if the brake is
released.
Set the maximum force to be
used for each of these objects.
• Turn ON the POT and NOT
signals.
• Disable them in the settings
when the POT and NOT
signals are not used.
Set the control mode according
to the command.
Wire correctly.
Turn ON the power.
Wire the power-ON circuit
correctly.
Replace the Servo Drive.
Set the correct data.
Wire correctly.
Wire correctly.
Set the speed command to "0."
Alternatively, change the mode
to position control mode.
Replace the Servo Drive.
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