Mitsubishi Electronics QD75D, QD75P user manual Current feed value during 2-axis speed control

9 MAJOR POSITIONING CONTROL

MELSEC-Q

Current feed value during 2-axis speed control

The following table shows the " Md.20 Current feed value" during 2-axis speed

control corresponding to the " Pr.21 Current feed value during speed control" settings. (Note that the reference axis setting values are used for parameters.)

"		Current feed value during speed
	Pr.21
				Md.20	Current feed value
		control" setting
0: Do not update current feed value			The current feed value at speed control start
			is maintained.
1: Update current feed value			The current feed value is updated.
2: Zero clear current feed value			The current feed value is fixed at 0.

Speed	In speed control	Speed
		t

Current feed value during speed control start is maintained

In speed control	Speed	In speed control
t		t
Current feed value is updated		0

(a) Current feed value not updated (b) Current feed value updated (c) Current feed value zero cleared

Restrictions

(1) Set "Positioning complete" in "

Da.1

Operation pattern". An axis error

"Continuous path control not possible (error code: 516)" will occur and the operation cannot start if "continuous positioning control" or "continuous path control" is set.

("Continuous positioning control" and "continuous path control" cannot be set in speed control.)

(2) Set the WITH mode in "

Pr.18

M code ON signal output timing" when using

an M code. The M code will not be output, and the M code ON signal will not turn ON if the AFTER mode is set.

(3) Set the "reference axis speed" in "

Pr.20

Interpolation speed designation

method". An "Interpolation mode error (error code: 523)" will occur and the operation cannot start if a composite speed is set.

(4)When either of two axes exceeds the speed limit, that axis is controlled with the speed limit value. The speeds of the other axes are limited at the ratios of

"Da.8

Command speed".

(Examples)

		Axis
			Axis 1 setting	Axis 2 setting
Setting item
	Pr.8	Speed limit value	4000.00mm/min	5000.00mm/min
	Da.8	Command speed	8000.00mm/min	6000.00mm/min

With the settings shown above, the operation speed in speed control is as follows.

Axis 1: 4000.00 mm/min (Speed is limited by

Pr.8

).

Axis 2: 3000.00 mm/min (Speed is limited at an ratio of an axis 1 command speed to an axis 2 command speed).

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