Remedies For Warnings - Mitsubishi Electric Melservo MR-J3-A Instruction Manual

9. TROUBLESHOOTING
Display Name
(Note) Watchdog
88888
Note. At power-on, "88888" appears instantaneously, but it is not an error.

9.3 Remedies for warnings

CAUTION
If AL.E6 or AL.EA 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 Configurator to refer to a factor
of warning occurrence.
Display Name
AL.92 Open battery
cable warning
AL.96 Home position
setting warning
AL.99 Stroke limit
warning
AL.9F Battery warning
AL.E0 Excessive
regenerative
warning
AL.E1 Overload
warning 1
Definition
CPU, parts faulty Fault of parts in servo amplifier
Alarm (88888) occurs if power is
switched on after disconnection of
all cables but the control circuit
power supply cable.
If an absolute position counter warning (AL.E3) occurred, always make home
position setting again. Otherwise, misoperation may occur.
POINT
When any of the following alarms has occurred, do not resume operation by
switching power of the servo amplifier OFF/ON repeatedly. The servo amplifier
and servo motor may become faulty. If the power of the servo amplifier is
switched OFF/ON during the alarms, allow more than 30 minutes for cooling
before resuming operation.
Excessive regenerative warning (AL.E0)
Overload warning 1 (AL.E1)
Definition
Absolute position
detection system battery
voltage is low.
Home position setting
could not be made.
The stroke end (LSP or
LSN) of the direction
which gave instructions
was turned off.
Voltage of battery for
absolute position
detection system
reduced.
There is a possibility that
regenerative power may
exceed permissible
regenerative power of
built-in regenerative
resistor or regenerative
option.
There is a possibility that
overload alarm 1 or 2
may occur.
Cause
Checking method
Cause
1. Battery cable is open.
2. Battery voltage supplied from the servo
amplifier to the encoder fell to about 3V
or less.
(Detected with the encoder)
1. Droop pulses remaining are greater than
the in-position range setting.
2. Command pulse entered after clearing
of droop pulses.
3. Creep speed high.
The limit switch became valid.
Battery voltage fell to 3.2V or less.
(Detected with the servo amplifier)
Regenerative power increased to 85% or
more of permissible regenerative power of
built-in regenerative resistor or
regenerative option.
Checking method
Call the status display and check
regenerative load ratio.
Load increased to 85% or more of overload
alarm 1 or 2 occurrence level.
Cause, checking method
Refer to AL.50,51.
9 - 8
Action
Change servo amplifier.
Action
Repair cable or changed.
Change battery.
Remove the cause of droop
pulse occurrence
Do not enter command pulse
after clearing of droop pulses.
Reduce creep speed.
Reexamine the
pattern to turn LSP/LSN ON.
Change the battery.
1. Reduce frequency of
positioning.
2. Change regenerative option
for the one with larger
capacity.
3. Reduce load.
Refer to AL.50, AL.51.
operation