Mitsubishi Electronics QD75P, QD75D user manual Speed switching Refer to Pr.19 Speed switching mode

9 MAJOR POSITIONING CONTROL

MELSEC-Q

(4)Speed switching (Refer to " Pr.19

Speed switching mode".)

(a)Standard speed switching mode

1)If the respective command speeds differ in the "positioning data currently being executed" and the "positioning data to carry out the next operation", the machine will accelerate or decelerate after reaching the positioning point set in the "positioning data currently being executed" and the speed will change over to the speed set in the "positioning data to carry out the next operation".

2)The parameters used in acceleration/deceleration to the command speed set in the "positioning data to carry out the next operation" are those of the positioning data to carry out acceleration/deceleration.

Speed switching will not be carried out if the command speeds are the same.

	V	Speed
		switching			Dwell time	Dwell time
	Positioning					t
	Da. 1 Operation pattern	11	11	11	01	00
		ON
Positioning start signal
	[Y10, Y11, Y12, Y13]
Start complete signal		ON
	[X10, X11, X12, X13] OFF
		ON
BUSY signal	[XC, XD, XE, XF] OFF
Positioning complete signal			ON
	[X14, X15, X16, X17] OFF

Fig. 9.4 Operation for the standard speed switching mode

3)Speed switching condition

If the movement amount is small in regard to the target speed, the current speed may not reach the target speed even if acceleration/deceleration is carried out. In this case, the machine is accelerated/decelerated so that it nears the target speed.

If the movement amount will be exceeded when automatic deceleration is required (Ex. Operation patterns "00", "01"), the machine will immediately stop at the designated positioning address, and a "insufficient movement distance warning (warning code: 513)" will occur.

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