Mitsubishi MELDAS MDS-C1 Instruction Manual page 281

Overvoltage
Alarm No.
The main circuit PN bus voltage exceeded the tolerable value.
75
Investigation details
1 Check the repeatability.
2 Check the power supply's alarm
history.
3 Check the power capacity.
4 Measure the voltage across wires.
• Is the voltage 170V or more even
when the motor is accelerating?
5 Measure the power voltage with a
synchroscope, and check whether
there is any distortion.
• Are there any other devices
causing the power distortion?
6 Check if there is any abnormality in
the unit's ambient environment.
(Ex. Noise, grounding)
External emergency stop setting error
Alarm No.
The rotary switch setting for the external emergency stop does not match the parameter setting.
76
Investigation details
1 Check the rotary switch settings and
parameter settings.
Power module overheat
Alarm No.
The power module's temperature protection function activated.
77
Investigation details
1 Confirm that the fan is rotating
correctly.
2 Check whether the heat dissipating
fins are dirty.
3 Measure the drive unit's ambient
temperature.
4 Check if there is any abnormality in
the unit's ambient environment.
(Ex. Ambient temperature, noise,
grounding)
6. Troubleshooting
Investigation results
The alarm occurs each time the
motor decelerates.
The alarm occurs occasionally.
Auxiliary regeneration frequency over
(E8) occurs just before the
overvoltage occurs.
Others.
The power capacity is insufficient.
The specified power capacity is
secured.
The voltage drops to 170V or less
occasionally.
The difference of the voltage across
wires is 10V or more.
The difference of the voltage across
wires is less than 10V.
The power voltage is distorted.
The power voltage waveform is not
abnormal.
No abnormality is found in particular.
The grounding is incomplete.
An alarm will occur easily if another
device operates.
Investigation results
When using external emergency stop:
• Add 0040h to the normal setting for SV036 or SP041, and set the power
supply's rotary switch to "4".
Investigation results
Large amounts of cutting oil or cutting
chips, etc., are adhered, or the
rotation is slow.
The fan is rotating properly.
Cutting oil or cutting chips, etc., are
adhered, and the fins are clogged.
The fins are normal.
55°C or more
Less than 55°C.
No abnormality is found in particular.
An abnormality was found in the
ambient environment.
6 - 36
Remedies
Investigate item 3.
Investigate item 2.
Limit the occurrence of the excessive
instantaneous regeneration by not
decelerating multiple axes at the
same time.
Investigate item 3.
Increase the power capacity.
Investigate item 4.
Increase the power capacity.
Improve the power phase balance.
Investigate item 5.
Improve the source of the distortion.
Install an AC reactor.
Investigate item 6.
Replace the unit.
Take remedies according to the
causes of the abnormality.
Ex. Incomplete grounding:
Additionally ground.
Noise: Noise measures for
other devices.
Remedies
Remedies
Clean or replace the fan.
Investigate item 2.
Clean the fins.
Investigate item 3.
Improve the ventilation and cooling
for the power distribution panel.
Investigate item 4.
If the alarm occurs even after the unit
temperature has dropped, replace
the unit.
Take remedies according to the
causes of the abnormality.
Ex. High temperature:
Check the cooling fan.
Incomplete grounding:
Additionally ground.
CV CR
CV CR
CV CR