Remedies For Warnings - Mitsubishi Electric MR-J3-B Instruction Manual

8. TROUBLESHOOTING
Display Name
52 Error excessive The deviation
8A USB
communication
time-out error
8E USB
communication
error
(Note) Watchdog
888
Note. At power-on, "888" appears instantaneously, but it is not an error.

8.3 Remedies for warnings

CAUTION
If E6, E7 or E9 occurs, the servo off status is established. If any other warning occurs, operation can be
continued but an alarm may take place or proper operation may not be performed. Use the optional servo
configuration software to refer to the cause of warning.
Remove the cause of warning according to this section. Use the optional MR Configulator (servo
configuration software) to refer to a factor of warning occurrence.
Definition
1. Acceleration/deceleration time
between the model constant is too small.
position and the
2. Torque limit value set with controller
actual servo motor
is too small.
position exceeds the
3. Motor cannot be started due to
parameter No.PC01
torque shortage caused by power
setting value (initial
supply voltage drop.
value: 3 revolutions).
4. Model loop gain 1 (parameter
No.PB07) value is small.
5. Servo motor shaft was rotated by
external force.
6. Machine struck something.
7. Encoder faulty
8. Wrong connection of servo motor.
Servo amplifier's output terminals U,
V, W do not match servo motor's
input terminals U, V, W.
9. SSCNET cable fault
Communication with 1. USB cable breakage.
MR Configurator in
test operation mode
stopped for longer
than the specified
time.
Serial communication
1. USB cable fault
error occurred
(Open cable or short circuit)
between servo
2. Communication device (e.g.
amplifier and
communication
personal computer) faulty
device (e.g. personal
computer).
CPU, parts faulty Fault of parts in servo amplifier
Alarm (888) occurs if power is
switched on after disconnection of
all cables but the control circuit
power supply cable.
If an absolute position counter warning (E3) occurred, always make home position
setting again. Otherwise, misoperation may occur.
Cause
Checking method
8 - 7
Action
Increase the acceleration/deceleration time
constant.
Increase the torque limit value.
1. Review the power supply capacity.
2. Use servo motor which provides larger
output.
Increase set value and adjust to ensure
proper operation.
1. When torque is limited, increase the limit
value.
2. Reduce load.
3. Use servo motor that provides larger
output.
1. Review operation pattern.
2. Install limit switches.
Change the servo motor.
Connect correctly.
Change the SSCNET cable.
Change the USB cable.
Change the USB cable.
Change the communication device (e.g.
personal computer).
Change servo amplifier.