Mitsubishi Electric A173UHCPU Programming Manual page 340

APPENDICES
Table 2.12 Servo Amplifier Error List (2000 to 2799) (Continued)
Error Amplifier
Code Type
Name
A
Position sensor
2020
error 2
M
Converter RD off
M
(400VAC series
2021
servo only)
Output ground
M
2024
fault
Absolute position
A
erase
2025
M
Battery alarm
A
2026 Module mismatch
Excessive
M
2030
regeneration
A
2031 Overspeed
M
Error Cause
Description
• During operation, communication
with the encoder is not normal.
• Fault in communication with the
encoder
• The servo-on (SON) signal turned
ON when the ready signal (RD) of
the converter is OFF.
1. Bus voltage is low.
2. Alarm occurring in converter.
• U, V, or W of the servo amplifier
output grounded
• In the absolute value encoder, the
voltage of the super capacitor in
the encoder is less than 2.5±0.2V.
• In the absolute value encoder,
speed was 500rpm or higher during
a power failure.
• The voltage of the supercapacitor
inside the absolute position sensor
has dropped.
• The battery voltage is low.
• Failure of battery cable or battery.
(Zeroing must be re-executed after
clearing the error.)
• The servo parameter (system
settings) does not match the real
servo amplifier.
• The frequency of ON/OFF
switching of the power transistor for
regeneration is too high. (Caution
is required since the regenerative
resistor could overheat.)
• Servo parameter (system settings)
setting error
• Incorrect wiring of regenerative
resistor
• Failure of regenerative resistor
• Power transistor for regeneration
damaged by short circuit
• The command speed is too high.
• Overshoot occurred during
acceleration.
• Encoder fault.
• Encoder cable fault or wiring
mistake.
• The motor rpm has exceeded
115% of the rated rpm.
• An overshoot has occurred
because the acceleration time
constant is too small.
• An overshoot has occurred
because the servo system is
unstable.
• Encoder fault.
When Error Checked Error Processing
At any time during operation
• At power-on of servo
amplifier
• At servo error reset
• When the servo amplifier
power is turned ON
• At the leading edge of the
PLC READY flag (M2000)
• When a servo error is reset
• When the power to the
servo system CPU is
turned ON
• At power-on of servo
amplifier
• At servo error reset
Immediate stop
At any time during operation
APP − 23
Corrective Action
• Check wiring between the encoder and
ADU.
• Change the servo motor (encoder).
• Check the encoder cable connector for
disconnection.
• Change the servo motor.
• Change the encoder cable.
• Remove the cause of the converter
alarm. Deactivate the alarm.
• Use a multimeter to check between the
U, V, and W terminals and the case.
• Use a multimeter and megger to check
between the U, V, and W terminals of
the motor and the core.
• Change the battery (MR-JBAT ).
• Check the wiring between encoder and
ADU.
• Turn the power ON for 2 to 3 minutes to
charge the supercapacitor, switch the
power OFF then ON again, and
execute a zeroing.
• Turn the servo amplifier power OFF,
then measure the battery voltage.
• Replace the servo amplifier battery.
• Reconsider the system settings.
• Reduce the frequency of acceleration
and deceleration or feed speed while
checking the servo monitor
regeneration level (%).
• Reduce the load.
• Increase the servomotor capacity.
• Check the servo parameters
(regenerative resistor and motor type
settings in the system settings).
• Connect the regenerative resistor
correctly.
• Replace the regenerative resistor.
• Replace the servo amplifier.
• Reconsider the command speed.
• Reconsider the servo parameter.
• Change the encoder.
• Check the wiring between encoder and
ADU.
• Check the motor rpm in the servo
parameters.
• Check if the number of pulses per
revolution and travel value per
revolution in the fixed parameters
match the machine specifications.
• If an overshoot occurs during
acceleration, check the acceleration
time and deceleration time in the fixed
parameters.
• If overshoot occurs, increase the speed
integral compensation by adjusting the
position loop gain / position control
gain 1, 2, speed loop gain / speed
control gain 1, 2 in the servo
parameters.
• Check the encoder cable for wire
breakage.
• Change the servo motor.