MITSUBISHI ELECTRIC Mitsubishi Programmable Logic Controller QD75D - Manual (Page 285)

8 - 7
MELSEC-Q
8 OPR CONTROL
Restrictions
A pulse generator with a zero signal is required.
When using a pulse generator without a zero signal, generate a zero signal using an
external signal.
Precautions during operation
(1) An error "Start at OP (error code: 201)" will occur if another machine OPR is
attempted after a machine OPR completion when the OPR retry function is not set
("0" is set in " Pr.48 OPR retry").
(2) Machine OPR carried out from the near-point dog ON position will start at the
" Pr.47 Creep speed".
(3) The near-point dog must be ON during deceleration from the OPR speed " Pr.47
Creep speed".
The workpiece will continue decelerating and stop if the near-point dog is turned OFF
before it has decelerated to the creep speed, thus causing an error "Dog detection
timing fault (error code: 203)".
t
V
ON
OFF
ON
OFF
OFF
0
ON
Near-point dog OFF
In error
Pr. 46 OPR speed
Pr. 47 Creep speed
In OPR Standing by
Inconsistent
Inconsistent Value the machine moved is stored Address at stop
Machine OPR start
(Positioning start signal)
OPR request flag
[ Md.31 Status : b3]
OPR complete flag
[ Md.31 Status : b4]
Md.26 Axis operation status
Md.34 Movement amount
after near-point dog ON
Md.20 Current feed value
Md.21 Machine feed value
Fig. 8.3 Operation when the near-point dog is turned OFF before the creep speed is reached
(4) When a machine OPR is stopped with the stop signal, perform a machine OPR again.
If the restart command is turned ON after a stop with the stop signal, an error "OPR
restart not possible" (error code: 209) occurs.