12 - 8 
MELSEC-Q
12   CONTROL SUB FUNCTIONS 
 
12.2.2 OP shift function  
When a machine OPR is carried out, the OP is normally established using the near-
point dog, stopper, and zero signal. However, by using the OP shift function, the 
machine can be moved a designated movement amount from the position where the 
zero signal was detected. A mechanically established OP can then be interpreted at 
that point.  
The OP shift function can be used without relation to "
Pr.43
 OPR method".  
 
The details shown below explain about the "OP shift function".  
  [1] Control details 
  [2] Setting range for the OP shift amount  
  [3] Movement speed during OP shift 
  [4] Control Precautions 
  [5] Setting method 
 
[1]   Control details 
The following drawing shows the operation of the OP shift function.  
 
Machine OPR start 
Pr.53 OP shift amount 
Speed selected by the " Pr. 56
Speed designation during OP 
shift"
Pr.47  Creep speed
Shift operation carried out after
the deviation counter clear and reset. 
Pr. 44  OPR direction 
Near-point dog
Pr. 46 OPR speed 
Zero signal 
 
Fig. 12.4 OP shift operation