Mitsubishi Electric C70 Setup Manual page 583

MITSUBISHI CNC
Appendix 2 Explanation of Alarms
Alarm No.
Power module overcurrent
32
Overcurrent protection function in the power module has started its operation.
Investigation details
Disconnect the power cable (U, V, W) from
the unit's terminal block and motor, and
1
check whether a short-circuit between the
power cable or whether conduction at both
end of wiring occurs with a tester.
Check the motor insulation with a (megger)
tester.
-Between motor power and ground earth
Check the unit capacity.
2
[1] The same size but smaller than the
selected capacity.
[2] The combination of the motor and axis is
alternated in a 2-axis unit.
3 Check the current loop gain parameters.
Jiggle the detector connectors (drive unit
4 side and detector side) and check if they are
disconnected.
Turn the power OFF, and check the detector
5
cable connection with a tester.
6 Check the repeatability.
Replace with another unit, and check
7 whether the fault is on the drive unit side or
detector side.
Check for any abnormalities in the unit's
ambient environment.
8
(Ex.: Ambient temperature, noise,
grounding)
Alarm No.
Overvoltage:
33
The main circuit bus voltage exceeded the tolerable value.
Investigation details
1 Is an external regenerative resistor used?
Is the short wire connected between P and
D terminal?
2
Are there any problems with the connection
condition?
Is the combination of the used regenerative
3
resistor and drive unit appropriate?
Is the connection of the regenerative
4 resistor or regeneration resistor cable
correct?
Is the regeneration resistor or the
regeneration resistor cable broken?
5 Disconnect the regenerative resistor
terminal and check the resistance value with
a tester.
The acceleration/deceleration time constant
is too short.
6
At acceleration/deceleration, has the speed
overshoot reached to the current limit?
566
Investigation results
[1] Before disconnecting the power cable,
the cable connector or screw has been
loosened.
[2] The short-circuit condition persists even
after disconnecting the cable from the unit
and motor.
There is no problem.
Less than 1M . (Grounding)
1M or more. (Normal)
The capacity is small.
The smaller capacity side was used in 2-
axis unit.
The motor meets the selected capacity.
Different from the standard parameter
settings.
Equivalent to the standard parameter
settings.
The connector is disconnected (or loose).
The connector is not disconnected.
Connection is faulty.
Connection is normal.
The state returns to normal once, but occurs
sometimes thereafter.
The error is always repeated.
The alarm is on the drive unit side.
The alarm is on the detector side.
Take remedies according to the causes of the abnormality in the ambient environment.
Investigation results
An external regenerative resistor is used.
A built-in regenerative resistor is used.
The wire is not connected.
The connector is disconnected.
The connector has a contact fault.
The connection is correct.
The combination is incorrect.
The combination is normal.
The connection is incorrect.
The connection is correct.
The regeneration resistor is broken.
Or the resistance value is large.
The regeneration resistor cable is broken.
The resistance value is normal.
Reached to the current limit.
The speed overshoot is applied.
The connection is normal.
Remedies
[1] Tighten it.
[2] Check the motor wiring.
[3] Replace the power cable.
Check the investigation item No. 2.
Replace the motor.
Check the investigation item No. 3.
Replace to the unit of the selected capacity
or change the axis.
Check the investigation item No. 3.
Adjust the value to the standard setting.
Check the investigation item No. 4.
Correctly install.
Check the investigation item No. 5.
Replace the detector cable.
Check the investigation item No. 6.
Check the investigation item No. 8.
Check the investigation item No. 7.
Replace the drive unit.
Replace the detector.
Remedies
Check the investigation item No. 3.
Check the investigation item No. 2.
Connect the wire.
Reconnect the connector.
Replace the connector.
Check the investigation item No.6.
Replace the correct regenerative resistor.
Check the investigation item No. 4.
Rewire.
Check the investigation item No. 5.
Replace the regenerative resistor.
Replace the cable.
Check the investigation item No. 6.
Increase the acceleration/deceleration time
constant.
Replace the drive unit.
SV SP
SV SP