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3. SIGNALS AND WIRING
3.3 Alarm occurrence timing chart
CAUTION When an alarm has occurred, remove its cause, make sure that the oper ation
signal is not being input, ensure safety, and reset the alarm before restarting
operation.
When an alarm occurs in the servo amplifier, the base circuit is shut off and the servo motor is coated to a
stop. Switch off the main circuit power supply in the external sequence. To deactivate the alarm, power
the control circuit off, then on or give the error reset or CPU reset command from the servo system
controller. However, the alarm cannot be deact ivated unless its cause is removed.
ON
OFF
ON
OFF
ON
OFF
NO YES
ON
OFF
1s NO YES
Main circuit
Control circuit power
Base circuit
Dynamic brake
Servo-on command
(from controller)
Alarm
Reset command
(from controller)
Valid
Invalid
Alarm occurs. Remove cause of trouble.
50ms or more 60ms or more
NO
Brake operation Br ake operation
Power on
Power off
(Note)
Note. Switch off the main circuit power as soon as an alarm occurs.
(1) Overcurrent, overload 1 or overload 2
If operation is repeated by switching control circuit power off, then on to reset the overcurrent (32),
overload 1 (50) or overload 2 (51) alarm after its occurrence, without removing its cause, the servo
amplifier and servo motor may become faulty due to temperature rise. Securely remove the cause of
the alarm and also allow about 30 minute s for cooling before resuming operation.
(2) Regenerative alarm
If operation is repeated by switching control circuit power off, then on to reset the regenerative (30)
alarm after its occurrence, the external regenerative brake resistor will generate heat, resulting in an
accident.
(3) Instantaneous power failure
Undervoltage (10) occurs if power is restored after a 60ms or longer power failure of the control circuit
power supply or after a drop of the bus voltage to or below 200VDC. If the power failure persists
further, the control circuit power switches off. When the power failure is reset in this state, the alarm
is reset and the servo amplifier returns to the initial state.