Mitsubishi Electric Melservo-J2-JR SERIES Instruction Manual page 132

9. TROUBLESHOOTING
Display Name
A. 17 Board error 2
A. 18 Board error 3
A. 20 Encoder error 2 Communication
A. 24 Motor outout
ground fault
A. 31 Overspeed
A. 32 Overcurrent
A. 33 Overvoltage
Definition
CPU/parts fault Faulty parts in the servo amplifier
Alarm (A. 17 or A. 18) occurs if
power is switched on after
Printed board fault
connectors CN1A, CN1B,
CNP2, CNP3 are disconnected.
Motor cable faulty
error occurred
(Encoder wiring broken or shorted)
between encoder
and servo amplifier.
Servo motor power cable insulation
Ground fault
occurred at the deteriorated.
servo motor outputs
(U,V and W phases)
of the servo
amplififer.
Speed has exceeded 1. Input command pulse frequency
the instantaneous exceeded the permissible
permissible speed. instantaneous speed frequency.
2. Small acceleration/deceleration
time constant caused overshoot to
be large.
3. Servo system is instable to cause
overshoot.
4. Electronic gear ratio is large
(parameters No. 3, 4)
5. Encoder faulty.
Current that flew is 1. Short occurred in servo amplifier
higher than the output phases U, V and W.
permissible current
2. Transistor (IPM) of the servo
of the servo
amplifier faulty.
amplifier.
Alarm (A. 32) occurs if power is
switched on after U, V and W
are disconnected.
3. Ground fault occurred in servo
amplifier output phases U, V and
W.
4. External noise caused the
overcurrent detection circuit to
misoperate.
Input value of Power supply voltage is outside the
converter bus permissible voltage range.
voltage reached or
exceeded 35V.
Cause
Checking method
Checking method
9 - 8
Action
Change the servo amplifier.
Repair or change the cable.
Change the cable.
Set command pulses correctly.
Increase acceleration/deceleration time
constant.
1. Re-set servo gain to proper value.
2. If servo gain cannot be set to proper
value:
1) Reduce load inertia moment ratio; or
2) Reexamine acceleration/
deceleration time constant.
Set correctly.
Change the servo motor.
Correct the wiring.
Change the servo amplifier.
Correct the wiring.
Take noise suppression measures.
Change battery.