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8. TROUBLESHOOTING
Alarm No.: A.E9
Name: Main circuit off warning
The servo motor stops.
Warning contents
Servo-on (SON) was switched on when the main circuit power is off.
The bus voltage decreased while the servo motor speed operates at 50r/min or slower.
Detailed
display
Detailed
Name
Cause
Checking method
Result
Action
E9.1
Servo-on
(SON) ON
when the
main circuit
is OFF.
1) Main circuit power supply
is off.
Check if the main
circuit power supply is
input.
Not input.
Switch on the main circuit
power.
Input.
Check 2).
2) Main circuit power supply
connector is disconnected.
Check the main circuit
power supply
connector.
The connector is
disconnected.
Connect properly.
No problem.
Check 3).
3) Main circuit power supply
voltage is low.
Check if the main
circuit power supply
voltage is the following
or less.
MR-JN- A:140VAC
MR-JN- A1:70VAC
MR-JN- A:140VAC
or less
MR-JN- A1:70VAC
or less
Raise the main circuit
power supply voltage.
MR-JN- A:Above
140VAC
MR-JN- A1:Above
70VAC
Check 4).
4) Servo amplifier for 1-
phase 200VAC input is
used for 100VAC power
supply circuit.
Check the model of
servo amplifier.
The model of servo
amplifier is "MR-JN-
A".
Replace the servo
amplifier whose model is
"MR-JN- A1".
The model of servo
amplifier is "MR-JN-
A1".
Check 5).
5) Faulty servo amplifier for
1-phase 100VAC input is
used.
Check if the charge
lamp is turned on.
The charge lamp is
not turned on.
Replace the servo
amplifier.
6) Bus voltage dropped.
Check the value of
status display Pn (bus
voltage).
The value of the
status display Pn
(bus voltage) is "1"
(overvoltage) or "2"
(low voltage).
Revise the wiring.
Check the power supply
capacity.
E9.2
Bus voltage
drop at low-
speed
rotation
1) When the set value of
parameter No. PC29
(function selection C-5) is
" 1 ", the bus voltage
decreased while the servo
motor operates at 50r/min
or slower.
Check the value of
status display Pn (bus
voltage).
The value is "1"
(undervoltage).
Check the power supply
capacity.
Increase the acceleration
time constant.
Summary of Contents for MELSERVO-JN Series
Page 31: ... 22 MEMO ...
Page 49: ...2 6 2 INSTALLATION MEMO ...
Page 181: ...5 30 5 DISPLAY AND OPERATION SECTIONS MEMO ...
Page 199: ...6 18 6 GENERAL GAIN ADJUSTMENT MEMO ...
Page 303: ...11 46 11 OPTIONS AND PERIPHERAL EQUIPMENT MEMO ...
Page 351: ...12 48 12 SERVO MOTOR MEMO ...
Page 445: ...13 94 13 POSITIONING MODE MEMO ...