Filter
Top Products
10 - 4
10. TROUBLESHOOTING
Display Name Definition
Cause
Action
A10 Undervoltage Power supply
voltage dropped.
MR-J3-
T:
160VAC or less
MR-J3-
T1:
83VAC or less
MR-J3-
T4:
280VAC or less
1. Power supply voltage is low. Check the power supply.
2. There was an instantaneous control
power failure of 60ms or longer.
3. Shortage of power supply capacity
caused the power supply voltage to
drop at start, etc.
4. The bus voltage dropped to the
following value or less.
MR-J3-
T: 200VDC
MR-J3-
T1: 158VDC
MR-J3-
T: 380VDC
5. Faulty parts in the servo amplifier
Checking method
Alarm (A10) occurs if power is
switched on after disconnection
of all cables but the control
circuit power supply cables.
Change the servo amplifier.
A12 Memory error 1
(RAM)
RAM, memory fault Faulty parts in the servo amplifier
Checking method
Alarm (any of A12 and A13)
occurs if power is switched on
after disconnection of all cables
but the control circuit power
supply cables.
Change the servo amplifier.
A13 Clock error Printed board fault
A15 Memory error 2
(EEP-ROM)
EEP-ROM fault 1. Faulty parts in the servo amplifier
Checking method
Alarm (A15) occurs if power is
switched on after disconnection
of all cables but the control
circuit power supply cables.
Change the servo amplifier.
2. The number of write times to EEP-
ROM exceeded 100,000.
A16 Encoder error 1
(At power on)
Communication error
occurred between
encoder and servo
amplifier.
1. Encoder connector (CN2)
disconnected.
Connect correctly.
2. Encoder fault Change the servo motor.
3. Encoder cable faulty
(Wire breakage or shorted)
Repair or change the cable.
4. Encoder cable type (2-wire, 4-wire)
selection was wrong in parameter
setting.
Correct the setting in the fourth digit of
parameter No. PC22.
A17 Board error CPU/parts fault Faulty parts in the servo amplifier
Checking method
Alarm (A17 or A19) occurs if
power is switched on after
disconnection of all cables but the
control circuit power supply cable.
Change the servo amplifier.
A19 Memory error 3
(Flash ROM)
ROM memory fault
A1A Motor
combination
error
Wrong combination
of servo amplifier
and servo motor.
Wrong combination of servo amplifier
and servo motor connected.
Use correct combination.
A20 Encoder error 2 Communication error
occurred between
encoder and servo
amplifier.
1. Encoder connector (CN2)
disconnected.
Connect correctly.
2. Encoder cable faulty
(Wire breakage or shorted)
Repair or change the cable.
3. Encoder fault
Change the servo motor.