12 - 5
MELSEC-Q
12 CONTROL SUB FUNCTIONS
(2) OPR retry operation when the workpiece is outside the range between the
upper/lower limits.
(a) When the direction from the workpiece to the OP is the same as the "
Pr.44
OPR direction", a
normal machine OPR is carried out.
Pr. 44 OPR direction
Upper limit
Lower limit
Movement range
Machine OPR start
OP
Zero signal
Near-point dog
(b) When the direction from the workpiece to the OP is the opposite direction from the "
Pr.44
OPR
direction", the operation carries out a deceleration stop when the near-point dog turns OFF, and
then carries out a machine OPR in the direction set in "
Pr.44
OPR direction".
Pr. 44 OPR direction
Near-point dog
Upper limit
Lower limit
Movement range
Machine OPR start
OP
Zero signal
Note) The above figures in (a) and (b) are examples where "
Pr.44
OPR direction" is set to "0:
Positive direction". When "0: Positive direction" is set in
Pr.44
, check that the limit switch
placed in the OPR direction acts as the upper limit. When "1: Negative direction" is set in
Pr.44
, check that the limit switch placed in the OPR direction acts as the lower limit. Incorrect
wiring of these limit switches may cause improper OPR retry operation. If any malfunction is
identified, check and correct "
Pr.6
Rotation direction setting" and the wiring.
Fig. 12.2 OPR retry operation from on limit (limit switch OFF)