Mitsubishi Electric MELSERVO MR-J3 A Series, Instruction Manual

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14 - 15
14. ABSOLUTE POSITION DETECTION SYSTEM
(4) At the time of emergency stop reset
(a) If the power is switched ON in the emergency stop state
The emergency stop state can be reset while the ABS data is being transferred.
If the emergency stop state is reset while the ABS data is transmitted, the base circuit is turned ON
95[ms] after resetting. If the ABS transfer mode (ABSM) is OFF when the base circuit is turned ON, the
ready (RD) is turned ON 5[ms] after the turning ON of the base circuit. If the ABS transfer mode (ABSM)
is ON when the base circuit is turned ON, it is turned OFF and then the ready (RD) is turned ON. The
ABS data can be transmitted after the emergency stop state is reset.
The current position in the servo amplifier is updated even during an emergency stop. When servo-on
(SON) and ABS transfer mode (ABSM) are turned ON during an emergency stop as shown below, the
servo amplifier transmits to the controller the current position latched when the ABS transfer mode
(ABSM) switches from OFF to ON, and at the same time, the servo amplifier sets this data as a position
command value. However, since the base circuit is OFF during an emergency stop, the servo-lock
status is not encountered. Therefore, if the servo motor is rotated by external force or the like after the
ABS transfer mode (ABSM) is turned ON, this travel is accumulated in the servo amplifier as droop
pulses. If the emergency stop is cleared in this status, the base circuit turns ON and the motor returns to
the original position rapidly to compensate for the droop pulses. To avoid this status, reread the ABS
data before clearing the emergency stop.
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
95[ms]
OFF
ON
5[ms]
Power
supply
Servo-on
(SON)
Emergency stop
(EMG)
ABS transfer mode
(ABSM)
ABS request
(ABSR)
ABS transmission
data ready
(ABST)
Send (ABS) data
Base circuit
Ready
(RD)
Reset
During transfer of ABS
ABS data
Operation
enabled