Mitsubishi Electric C70 Setup Manual page 594

Alarm No.
Safety observation: Feedback speed error
5E
In safety monitoring mode, the motor speed was detected to exceed the safe speed.
Investigation details
1 Check the DI input timing.
Check the wiring and setting environment.
1) Correctly grounded?
2) Any noise generating devices around the
2
unit?
3) Are the speed/position detector cables
correctly shielded?
Alarm No.
External contactor error
5F
A contact of the external contactor is welding.
Investigation details
Check whether the contactor's contact has
1
melted.
Check whether the axis where an alarm
2
occurred was a contactor control axis.
Alarm No.
Power supply: Power module overcurrent
61
Overcurrent protection function in the power module of power supply has started its operation.
Investigation details
Check the state of the operation when the
1
alarm occurs, and check the repeatability.
Check the load state of all motors (during
2
stopped).
Check the power capacity of the facility.
3 Check the capacity of the step-down
transformer (KVA).
Measure the voltage across wires.
4 Is the voltage 170V or more even when the
motor is accelerating?
Check whether there is any device
5
(machine) causing the power distortion.
Check if there is any abnormality in the
6 unit's ambient environment.
(Ex. Noise, grounding, etc.)
Investigation results
The feedback speed and safe speed limit
value are the same.
The feedback speed is slower than the safe
speed.
1) The grounding is incomplete.
2) The alarm occurs easily when a specific
device operates.
3) The cable is not correctly shielded.
No abnormality is found in particular.
Investigation results
The contactor is melted.
The contactor is not melted.
The alarm occurred at the axis where the
contactor control is not executed.
The alarm occurred at the axis where the
contactor control is executed.
Investigation results
The alarm occurs immediately after
200VAC is supplied or after READY is
turned ON.
The alarm occurs occasionally during
READY ON.
The alarm occurs after continuous operation
for a long time.
The unit is hot.
The total load of all motors exceeds the
rated capacity of the power supply unit.
The total does not exceed the capacity.
The power capacity of the facility 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.
Abnormal noise is heard from an AC reactor
when stopping at the servo ON.
Abnormal noise is not heard.
Take remedies according to the causes of the abnormality in the ambient environment.
Appendix 2.16 Troubleshooting
Remedies
Reduce the commanded speed on the NC
side or increase the safe speed limit value.
Replace the drive unit.
Correctly ground.
Use noise measures on the device
described on the left.
Correctly shield the cable.
Replace the drive unit.
Remedies
Replace the contactor.
Check the investigation item No. 2.
Check the parameter.(SVJ3/SPJ3)
With contactor control
Servo:SV082, Spindle:SP227
0800h is added to the setting value.
Without contactor control
Change "Bit A,B" to "00" in the parameter
above.
Replace the drive unit.
Remedies
Replace the unit.
Check the investigation item No. 3.
Check the investigation item No. 2.
Lower the motor load and operation
frequency.
Check the investigation item No. 3.
Increase the power capacity of the facility.
Check the investigation item No. 4.
Increase the power capacity of the facility.
Improve the power phase balance.
Check the investigation item No. 5.
Improve the source of the distortion.
For example, when abnormal noise is heard
from another machine that is in operation,
move the wiring to the power which is far
from the machine's power supply.
Check the investigation item No. 6.
C70 Setup Manual
SV SP
SV SP
CV
577