15.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 80[ms] after resetting. If the ABS transfer mode signal (ABSM) is OFF when the base circuit is turned ON, the ready signal (RD) is turned ON 20[ms] after the turning ON of the base circuit. If the ABS transfer mode signal (ABSM) is ON when the base circuit is turned ON, it is turned OFF and then the ready signal (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.

Power

ON

 

 

 

 

 

 

 

 

 

 

supply

OFF

 

 

 

 

Servo-on

 

 

 

ON

 

 

 

 

 

 

 

 

 

(SON)

 

 

 

 

OFF

 

 

 

 

 

Emergency stop

ON

 

(EMG)

 

 

 

 

OFF

 

 

 

 

 

ABS transfer mode

ON

 

(ABSM)

 

 

 

 

OFF

 

 

 

 

 

ABS request

ON

 

(ABSR)

 

 

 

 

OFF

 

 

 

 

 

Send data ready

ON

 

(TLC)

 

 

 

 

OFF

 

 

 

 

 

Send (ABS) data

 

 

ON

Base circuit

 

 

OFF

Ready

ON

 

(RD)

OFF

 

Reset

During transfer of ABS

ABS data

80[ms]

20[ms]

Operation

enabled

15 - 15

Page 266
Image 266
Mitsubishi Electronics MR-J2S- A instruction manual At the time of emergency stop reset, Emg Off