8 OPR CONTROL

8.2.8 OPR method (6): Count method 2)

MELSEC-Q

The following shows an operation outline of the "method 2)" OPR method.

The "count method 2)" method is effective when a "zero signal" cannot be received. (Note that compared to the "count method 1)" method, using this method will result in more deviation in the stop position during machine OPR.)

Operation chart

The machine OPR is started.

(The machine begins the acceleration designated in " Pr.51 OPR acceleration time selection", in the

1)

Pr.44 OPR direction". It then moves at the "

Pr.46 OPR speed" when the

direction designated in "

acceleration is completed.)

2)The machine begins decelerating when the near-point dog ON is detected.

3)The machine decelerates to the " Pr.47 Creep speed", and subsequently moves at that speed. The pulse output from the QD75 will stop and the machine OPR will be completed when the machine

4)moves the movement amount set in " Pr.50 Setting for the movement amount after near-point dog ON " from the near-point dog ON position.

Pr. 46 OPR speed

V

Pr.50 Setting for the movement amount

 

 

after near-point dog ON

Creep speed

t

Md.34 Movement amount after near-point dog ON 1

 

Leave sufficient distance from the OP

ON

position to the near-point dog OFF

Near-point dog OFF

 

 

 

 

ON

 

 

Machine OPR start

OFF

 

 

 

 

(Positioning start signal)

 

 

 

 

 

 

 

 

 

 

 

ON

 

 

OPR request flag

OFF

 

 

 

 

[ Md.31 Status : b3]

 

 

 

 

 

 

 

 

 

 

 

 

 

ON

OPR complete flag

OFF

 

 

 

 

[ Md.31 Status : b4]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Md.26 Axis operation status Standing by

In OPR

Standing by

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Md.34 Movement amount

Inconsistent

0

Value of 1 .

after near-point dog ON

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Md.20 Current feed value

 

 

 

 

 

 

 

Inconsistent Value the machine moved is stored

OP address

 

Md.21 Machine feed value

Fig. 8.14 Count method 2) machine OPR

8 - 18

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Mitsubishi Electronics QD75P, QD75D user manual OPR method 6 Count method, Machine OPR is started, Direction designated