Trouble At Start-Up - Mitsubishi Electric Melservo MR-J3-A Instruction Manual

4. STARTUP

4.2.6 Trouble at start-up

CAUTION
The following faults may occur at start-up. If any of such faults occurs, take the corresponding action.
(1) Troubleshooting
No. Start-up sequence
1 Power on
2 Switch on servo-on
(SON).
3 Enter input
command.
(Test operation)
4 Gain adjustment
5 Cyclic operation
Excessive adjustment or change of parameter setting must not be made as it will
make operation instable.
POINT
Using the optional MR Configurator, you can refer to unrotated servo motor
reasons, etc.
Fault
LED is not lit. Not improved if connectors CN1,
LED flickers. CN2 and CN3 are disconnected.
Improved when connectors CN1 is
disconnected.
Improved when connector CN2 is
disconnected.
Improved when connector CN3 is
disconnected.
Alarm occurs. Refer to chapter 9 and remove cause.
Alarm occurs. Refer to chapter 9 and remove cause.
Servo motor shaft is 1. Check the display to see if the
not servo-locked servo amplifier is ready to
(is free). operate.
2. Check the external I/O signal
indication (section 6.7) to see if
the servo-on (SON) is ON.
Servo motor does Check
not rotate. pulses for the status display
(section 6.3).
Servo motor run in
reverse direction.
Rotation ripples Make gain adjustment in the
(speed fluctuations) following procedure:
are large at low 1. Increase the auto tuning
speed. response level.
2. Repeat acceleration and
deceleration several times to
complete auto tuning.
Large load inertia If the servo motor may be run with
moment causes the safety, repeat acceleration and
servo motor shaft to deceleration several times to
oscillate side to side. complete auto tuning.
Position shift occurs Confirm the cumulative command
pulses, cumulative feedback
pulses and actual servo motor
position.
Investigation
1. Power supply voltage fault
2. Servo amplifier is faulty.
Power supply of CN1 cabling is
shorted.
1. Power supply of encoder
2. Encoder is faulty.
Power supply of CN3 cabling is
shorted.
1. Servo-on (SON) is not input.
2. External 24VDC power is not
cumulative command 1. Wiring mistake
2. No pulses is input.
1. Mistake in wiring to controller.
2. Mistake in setting of parameter
Gain adjustment fault
Gain adjustment fault
Pulse counting error, etc.
due to noise.
4 - 7
Possible cause
cabling is shorted.
(Wiring mistake)
supplied to DICOM.
(a) For open collector pulse
train input, 24VDC power is
not supplied to OPC.
(b) LSP and LSN are not on.
No. PA14.
Reference
Chapter 9
Chapter 9
Section 6.7
Section 6.3
Chapter 5
Chapter 7
Chapter 7
(2) in this
section