beautypg.com

Melsec-q, 3] precautions during control – MITSUBISHI ELECTRIC Mitsubishi Programmable Logic Controller QD75D User Manual

Page 509

background image

12 - 33

MELSEC-Q

12 CONTROL SUB FUNCTIONS

[2] Wiring the hardware stroke limit

When using the hardware stroke limit function, wire the terminals of the QD75

upper/lower limit stroke limit as shown in the following drawing.

(When "

Pr.22

Input signal logic selection" is set to the initial value)

QD75

FLS

RLS

COM

24VDC

Note) Connect the upper and lower limit switches to the directions of increasing and decreasing

current feed values respectively. When these switches are connected in wrong directions, the
hardware stroke limit function does not operate properly and the motor does not stop.
For "

Pr.6

Rotation direction setting", refer to "5.2.1 Basic parameters 1".

Fig. 12.20 Wiring when using the hardware stroke limit

[3] Precautions during control

(1) If the machine is stopped outside the QD75 control range (outside the

upper/lower limit switches), or if stopped by hardware stroke limit detection,
the "OPR control", "major positioning control", and "high-level positioning
control" cannot start. To carry out these types of control again, return the
workpiece to the QD75 control range by a "JOG operation", "inching
operation" or "manual pulse generator operation".

(2) When "

Pr.22

Input signal logic selection" is set to the initial value, the

QD75 cannot carry out the positioning control if FLS (upper limit signal) is
separated from COM or RLS (lower limit signal) is separated from COM
(including when wiring is not carried out).

[4] When the hardware stroke limit function is not used

When not using the hardware stroke limit function, wire the terminals of the QD75

upper/lower limit stroke limit as shown in the following drawing.

When the logic of FLS and RLS is set to "positive logic" using "

Pr.22

Input

signal logic selection", positioning control can be carried out even if FLS and RLS

are not wired.

(For details, refer to Section 13.4 "External I/O signal logic switching function".)

QD75

FLS

RLS

COM

24VDC

Fig. 12.21 Wiring when not using the hardware stroke limit function

(When "

Pr.22

Input signal logic selection" is the initial value)