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MELSEC-Q
 
6   SEQUENCE PROGRAM USED FOR POSITIONING CONTROL 
 
[2]   Types of stop processes 
The operation can be stopped with deceleration stop, sudden stop or immediate 
stop. 
 
(1) Deceleration stop 
1 
 
The operation stops with "deceleration time 0 to 3" (
Pr.10
, 
Pr.28
, 
Pr.29
, 
Pr.30
). 
Which time from "deceleration time 0 to 3" to use for control is set in positioning 
data (
Da.4
). 
 
(2) Sudden stop 
 
The operation stops with "
Pr.36
Sudden stop deceleration time". 
 
(3)  Servo OFF or free run (The operation stops with dynamic brake or 
electromagnetic brake.) 
 
The operation does not decelerate. 
The QD75 immediately stops the command, but the operation will coast for the 
droop pulses accumulated in the servo amplifier deviation counter. 
 
Actual deceleration time
Set deceleration time
Positioning speed
Actual sudden stop 
deceleration time
Pr. 36 Sudden stop 
deceleration time
Coast for the droop pulses accumulated 
in the servo amplifier deviation counter.
Positioning speed Positioning speed
 
 
Fig. 6.15 Types of stop processes 
 
 
REMARK 
1  "Deceleration stop" and "sudden stop" are selected with the details parameter 2 
"stop group 1 to 3 sudden stop selection". (The default setting is "deceleration 
stop".)