Mitsubishi Electric C70, Setup Manual

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C70 Setup Manual
Appendix 2.16 Troubleshooting
581
Alarm No.
70
Power supply: External emergency stop error
A mismatch of the external emergency stop input and CNC emergency stop input continued for 30 seconds.
Investigation details Investigation results Remedies CV
1
Check the connection between external
emergency stop and NC emergency stop.
Not wired.
Correctly wire the external emergency stop
and NC emergency stop.
2
Check if there is any abnormality in the
unit's ambient environment.
No abnormality is found in particular. Replace the drive unit.
The grounding is incomplete.
Take remedies according to the causes of
the abnormality. Additionally ground and
review.
Alarm No.
71
Power supply: Instantaneous power interruption
The power was momentarily interrupted.
Investigation details Investigation results Remedies CV
1
Investigate the sequence to check whether
the contactor has been turned OFF with an
emergency stop button, etc. The contactor has been turned OFF
externally.
Review the machine sequence.
When turning the contactor OFF with
external means, such as an emergency stop
button, this alarm can be avoided by
inputting NC emergency stop at the same
time.
The contactor has not been turned OFF. Check the investigation item No. 2.
2 Check the repeatability.
The alarm occurs each time READY is
turned ON.
Check the investigation item No. 3.
The alarm occurs at a certain operation.
Check the investigation item No. 1.
If there is no problem, check the
investigation item No. 3.
The alarm occurs occasionally during
operation.
Check the investigation item No. 4.
3
Check whether the power input wire and
contactor are correctly wired.
The wiring is incorrect. Correctly connect.
There is no problem. Check the investigation item No. 4.
4
Check the power voltage waveform with a
synchroscope.
An instantaneous power failure or voltage
drop occurs frequently.
Correct the power facility.
There is no problem. Replace the unit.
Alarm No.
72
Power supply: Fan stop
A cooling fan built in the power supply unit stopped, and overheat occurred in the power module.
Investigation details Investigation results Remedies CV
1
Turn the unit power ON again, and confirm
the rotation of the fan.
Note) Assure more than 10 seconds for the
time from when the power is turned OFF till
when it is turned ON. For the fan used for
the drive unit, assuring more than 10
seconds for the time from when the power is
turned OFF till when it is turned ON is
required.
The fan is rotating, and an alarm did not
occur again.
Continue to use.
The power may be turned ON without
assuring more than 10 seconds for the time
from when the power is turned OFF till when
it is turned ON.
Leave for more than 10 seconds, and turn
the power ON again.
The fan did not rotate. Or, an alarm
occurred again.
Check the investigation item No. 2.
2
Check if the connector connected to a fan is
disconnected. The connector is disconnected. Correctly connect the connector.
The connector is not disconnected. Check the investigation item No. 3.
3
Check if oil or cutting chips are adhered to
the fan.
Oil or cutting chips are adhered.
Improve the use environment and replace
the drive unit.
Oil or cutting chips are not adhered.
The cable may be broken.
Replace the drive unit.