Mitsubishi melservo-j2 series Instruction Manual page 208

11. TROUBLESHOOTING
Display Name
A.31 Overspeed
A.32 Overcurrent
A.33 Overvoltage
A.35 Command pulse
frequency alarm
Definition
Speed has exceeded 1. Input command pulse frequency
the instantaneous exceeded the permissible instantaneous
permissible speed. speed frequency.
2. Small acceleration/deceleration time
constant caused overshoot to be large.
3. Servo system is instable to cause
overshoot.
4. 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 amplifier
of the servo
faulty.
amplifier.
3. Ground fault occurred in servo
amplifier output phases U, V and W.
4. External noise caused the overcurrent
detection circuit to misoperate.
Converter bus 1. Lead of built-in regenerative brake
voltage exceeded resistor or regenerative brake option is
400V. open or disconnected.
2. Regenerative transistor faulty.
3. Wire breakage of built-in regenerative
brake resistor or regenerative brake
option
4. Capacity of built-in regenerative brake
resistor or regenerative brake option is
insufficient.
Input pulse 1. Pulse frequency of the manual pulse
frequency of the generator is too high.
manual pulse
2. Noise entered the pulses of the manual
generator is too high.
pulse generator.
3. Manual pulse generator failure
Cause
Checking method
Alarm (A.32) occurs if power is
switched on after U,V and W
are disconnected.
11 - 5
Action
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.
Change the servo motor.
Correct the wiring.
Change the servo amplifier.
Correct the wiring.
Take noise suppression
measures.
1. Change lead.
2. Connect correctly.
Change servo amplifier
1. For wire breakage of built-in
regenerative brake resistor,
change servo amplifier.
2. For wire breakage of
regenerative brake option,
change regenerative brake
option.
Add regenerative brake option
or increase capacity.
Change the pulse frequency to a
proper value.
Take action against noise.
Change the manual pulse
generator.