Mitsubishi MELDAS MDS-C1 Instruction Manual page 271

Overload 2
Alarm No.
With the servo, a current command exceeding 95% of the unit's maximum current continued for one
51 second or more. With the spindle, a load exceeding the continuous rating continued for 30 minutes or
more.
Investigation details
1 Did the alarm occur immediately after
READY ON?
2 Check that the PN voltage is supplied
to the drive unit.
• Is the CHARGE lamp ON?
3 Check the motor power cable (U, V,
W phases).
• The power cable is not connected.
• Is the cable connected to the motor
for another axis?
4 Check the detector cable connection.
• Is the cable connected to the motor
for another axis?
5 Check whether the machine has
collided.
6 Check whether the current value on
the NC Servo Monitor screen is
saturated during
acceleration/deceleration.
7 Check the detector FB.
8 Check the load meter value.
9 Check the PLG output waveform.
Excessive error 1
Alarm No.
The difference between the motor's actual position at servo ON and the theoretical position exceeded
52
the setting value.
Investigation details
1 Check the excessive error detection
width.
SV023 (Servo)
SP102 (Orientation control)
SP154, SP155 (C-axis control)
SP177, bitD, SP186 (Spindle
synchronous control)
SP193, bitD, SP218 (Synchronous
tap)
2 Check the position detector polarity.
SV017, bit4 (Servo)
SP097, bit5 (Orientation control)
SP129, bit5 (C-axis control)
SP177, bit5 (Spindle synchronous
control)
SP193, bit5 (Synchronous tap
control)
3 Check the alarm No. "51" items.
6. Troubleshooting
Investigation results
The alarm occurred after ready ON
before operation starts.
The alarm occurred after normal
operation.
The voltage is not supplied.
Approx. 300V is correctly supplied.
The connections are incorrect.
The connections are correct.
The connections are incorrect.
The connections are correct.
The machine has collided.
The machine has not collided.
The current is saturated during
acceleration/deceleration.
The current value during
acceleration/deceleration is
appropriate.
The FB signal is abnormal.
The FB signal is normal.
The load is large.
The load is not large.
There is a problem.
Normal
Investigation results
The excessive error detection width is
too small.
Servo standard value:
RAPID
÷ 2
SV023 =
60 × PGN1
For the spindle, a value larger than
the droop amount:
Droop amount =
Spindle rotation speed × No. of pulses
60 × position loop gain
Appropriate values are set.
The polarity is reversed.
Normal.
6 - 26
Remedies
Investigate item 2.
Investigate item 5.
Correctly supply the PN voltage.
Investigate item 3.
Connect correctly.
Investigate item 4.
Connect correctly.
Investigate item 5.
Check the machining program and
soft limit settings.
Investigate item 6.
Increase the acceleration/
deceleration time constant.
Investigate item 7.
Replace the detector.
(With the absolute position system,
the zero point must be established.)
Replace the drive unit.
Lower the load.
Investigate item 9.
Adjust the PLG output waveform.
Replace the drive unit.
Remedies
Set appropriate values.
Investigate item 2.
Correctly set the parameters.
Investigate item 3.
SV SP
SV SP