9MAJOR POSITIONING CONTROL

9.2.14 3-axis speed control

MELSEC-Q

In "3-axis speed control" (" Da.2 Control system" = Forward run: speed 3, Reverse

run: speed 3), control is carried out in the 3-axis direction in which the positioning data has been set by continuously outputting pulses for the speed set in " Da.8 Command

speed" until the input of a stop command.

The two types of 3-axis speed control are "Forward run: speed 3" in which the control

starts in the forward run direction, and "Reverse run: speed 3" in which control starts in the reverse run direction.

(Refer to Section 9.1.6 "Interpolation control" for the combination of the reference axis with the interpolation axes.)

Operation chart

The following chart shows the operation timing for 3-axis (axes 1, 2, and 3) speed control with axis 1 as the reference axis.

The "in speed control" flag ( Md.31 Status: b0) is turned ON during speed control. The "positioning complete signal" is not turned ON.

 

 

V

Da. 8

Command speed

Interpolation axis (axis 3)

 

 

 

t

 

 

V

Da. 8

Command speed

Interpolation axis (axis 2)

 

 

 

t

 

 

V

Da. 8

Command speed

Referense axis (axis 1)

 

 

 

t

 

 

ON

Positioning start signal

OFF

 

[Y10]

 

 

 

 

ON

BUSY signal

OFF

 

[XC,XD,XE]

 

Positioning complete signal

OFF

 

[X14,X15,X16]

 

Does not turn ON even when control is stopped by stop command.

ON

Axis stop signal (stop command) (Either Y4,Y5 or Y6)

In speed control flag

Md.31 Status: b0

OFF

ON

OFF

Fig. 9.11 3-axis speed control operation timing

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Image 373
Mitsubishi Electronics QD75D, QD75P user manual 14 3-axis speed control, 11 3-axis speed control operation timing