Mitsubishi Electronics QD75P Sub functions specifically for machine OPR, OPR retry function

12 CONTROL SUB FUNCTIONS

12.2 Sub functions specifically for machine OPR

MELSEC-Q

The sub functions specifically for machine OPR include the "OPR retry function" and "OP shift function". Each function is executed by parameter setting.

12.2.1 OPR retry function

When the workpiece goes past the OP without stopping during positioning control, it may not move back in the direction of the OP although a machine OPR is commanded, depending on the workpiece position. This normally means the workpiece has to be moved to a position before the near-point dog by a JOG operation, etc., to start the machine OPR again. However, by using the OPR retry function, a machine OPR can be carried out regardless of the workpiece position.

The details shown below explain about the "OPR retry function".

[1]Control details

[2]Precautions during control

[3]Setting the OPR retry function

[1]Control details

The following drawing shows the operation of the OPR retry function.

(1)OPR retry point return retry operation when the workpiece is within the range between the upper and lower limits.

1) The movement starts in the "

Pr.44

OPR direction" by a machine OPR start.

2)The operation decelerates when the limit signal OFF is detected.

3)After stopping at detection of the limit signal OFF, the operation moves at the "

direction opposite to the " Pr.44 OPR direction".

Pr.46

OPR speed" in the

4)The operation decelerates when the near-point dog turns OFF.

5)After stopping due to the near-point dog OFF, a machine OPR is carried out in the " direction".

6)Machine OPR completion

2)

Pr.44

OPR

5) 1)

6) 3)

4)

ON Limit signal OFF

Near-point dog

Zero signal

Fig. 12.1 OPR retry operation by limit signal detection

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