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Protection
*
Overcurrent
error
Cause
The current flowing in the converter
is larger than the specified value.
1) The amplifier failed (due to defective
circuits or IGBT parts).
2) Motor wires (U, V and W) are shorted.
3) Motor wires are grounded.
4) Motor burned
5) Poor connection of Motor wires
6) The relay for the dynamic brake is
melted and stuck due to the frequent
Servo-ON/OFF.
7) The motor is not compatible with the
amplifier.
8) Pulse input and Servo-ON occurs
simultaneously, or pulse input
occurs faster than Servo-ON.
Countermeasures
1) Disconnect the motor wires, and enter
Servo-ON. If this trouble happens imme-
diately, replace the amplifier with a new
one (that is working correctly).
2) Check if the U. V and W wires are shorted
at the connections. Reconnect them, if
necessary.
3) Measure the insulation resistance be-
tween U/V/W and earth wire. If the resis-
tance is not correct, replace the motor
with a new one.
4)
Measure the resistance between U, V and
W. If they are unbalanced, replace the mo-
tor with a new one.
5) Check if the U/V/W connector pins are
firmly secured with screws. Loosened
pins should be fixed firmly.
6) Replace the amplifier with a new one. Do
not start or stop the motor by entering
Servo-ON or OFF.
7) Check the capacity of the motor and am-
plifier on the nameplate. If the motor is
not compatible with the amplifier, replace
it with a correct one.
8) Pulse input should occur after at least
100 ms following Servo-ON. Refer to Ap-
pendix "Timing Chart".
Protective Functions