Mitsubishi Electronics MR-J2S- A Precautions for alarm occurrence, Son Off, Alm Off, Res Off

3. SIGNALS AND WIRING

3.5 Alarm occurrence timing chart

When an alarm has occurred, remove its cause, make sure that the operation CAUTION 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 reset the alarm, switch the control circuit power supply off, then on.

However, the alarm cannot be reset unless its cause of occurrence is removed.

Control power	ON
supply	OFF
Base circuit	ON
	OFF
Dynamic brake	Valid
	Invalid
Servo-on	ON
(SON)	OFF
Ready	ON
(RD)	OFF
Trouble	ON
(ALM)	OFF
Reset
	ON
(RES)	OFF

	Power off	Power on
Brake operation	Brake operation

1s

Alarm occurs. 50ms or more 60ms or more

Remove cause of trouble.

Precautions for alarm occurrence

1)Overcurrent, overload 1 or overload 2

If operation is repeated by switching control circuit power off, then on to reset the overcurrent (AL.32), overload 1 (AL.50) or overload 2 (AL.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 minutes for cooling before resuming operation.

2)Regenerative alarm

If operation is repeated by switching control circuit power off, then on to reset the regenerative (AL.30) alarm after its occurrence, the external regenerative brake resistor will generate heat, resulting in an accident.

3)Instantaneous power failure

Undervoltage (AL.10) occurs if power is restored after a 60ms or longer power failure of the control power supply or after a drop of the bus voltage to or below 200VDC. If the power failure persists further, the control power switches off. When the power failure is reset in this state, the alarm is reset and the servo motor will start suddenly if the servo-on signal (SON) is on. To prevent hazard, make up a sequence which will switch off the servo-on signal (SON) if an alarm occurs.

4)In position control mode (incremental)

When an alarm occurs, the home position is lost. When resuming operation after deactivating the alarm, make a home position return.

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