Mitsubishi Electric MELSERVO-J4 Instruction Manual page 44

1. TROUBLESHOOTING FOR SERVO AMPLIFIER (DRIVE UNIT)
Alarm No.: 25 Name: Absolute position erased
Alarm content
Detail
Detail name
No.
25.2 Scale (1) After the scale
measurement
encoder -
Absolute
position erased
(2) The battery was
(3) The power was turned
(4) The battery voltage is
(5) The voltage has
(6) A battery cable is
(7) There is a loose
(8) The servo amplifier is
(9) The scale
The absolute position data is faulty.
Power was switched on for the first time in the absolute position detection system.
After the scale measurement encoder was set to the absolute position detection system, the power was
switched on for the first time.
Cause
Check if this is the
measurement encoder first time to switch on
was set to the absolute the power after the
position detection scale measurement
system, the power was encoder was set to
switched on for the first the absolute position
time. detection system.
Check if the battery
removed (replaced) was removed when
when the control circuit the control circuit
power supply was off. power supply was off.
Check if the power
off with the battery was turned off in this
disconnected from state.
CN4.
Check the battery
low. The battery is voltage with a tester.
consumed.
Check if a
dropped greatly in the recommended cable
encoder cable wired to is used for the
the battery. encoder cable.
Check for the loose
malfunctioning. connection with a
tester.
Check for the loose
connection of the connection with a
encoder cable on the tester. Measure the
scale measurement voltage on the scale
encoder side. measurement
encoder side.
Replace the servo
malfunctioning. amplifier, and then
check the
repeatability.
Replace the scale
measurement encoder measurement
is malfunctioning. encoder, and then
check the
repeatability.
Check method Check result
This is the first time. Check that the
This is not the first
time.
It was removed.
It was not removed.
It was turned off.
It was not turned off. Check (4).
It is less than 3 V
DC.
It is 3 V DC or more. Check (5).
It is not used.
It is used.
It has a failure.
It has no failure.
It has a failure.
It has no failure.
It is not repeatable.
It is repeatable.
It is not repeatable.
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Action Target
[B]
battery is mounted [WB]
correctly, and make [GF]
home position return.
Check (2).
Check that the
battery is mounted
correctly, and make
home position return.
Check (3).
Check that the
battery is mounted
correctly, and make
home position return.
Replace the battery.
Use a
recommended wire.
Check (6).
Replace the battery
cable.
Check (7).
Repair or replace
the encoder cable.
Check (8).
Replace the servo
amplifier.
Check (9).
Replace the scale
measurement
encoder.