Mitsubishi Electronics QD75D Override function, Feedrate becomes a value of 1 or less. When

12CONTROL SUB FUNCTIONS

12.5.2 Override function

MELSEC-Q

The override function changes the command speed by a designated percentage (1 to 300%) for all control to be executed.

The speed can be changed by setting the percentage (%) by which the speed is

changed in "

Cd.13

Positioning operation speed override".

However, when a machine OPR is performed, an override cannot be made after a deceleration start to the creep speed following the detection of near-point dog ON.

[1]Control details

[2]Precautions during control

[3]Setting the override function

[1]Control details

The following shows that operation of the override function.

1)A value changed by the override function is monitored by " Md.22 Feedrate". (When Md.22 " becomes "0", the warning "Less than minimum

speed" (warning code: 110) is generated and the axis is controlled in the then speed unit of "1".)

2) If "

Cd.13

Positioning operation speed override" is set to 100%, the speed

will not change.

3) If "

Cd.13

Positioning operation speed override" is set a value less than

100%, control will be carried out at speed unit "1" at the time "

Md.22

Feedrate" becomes a value of "1" or less. (When

Md.22

becomes "0", the

warning "Less than minimum speed (warning code: 110)" is generated and the axis is controlled in the then speed unit of "1".)

4)If there is not enough remaining distance to change the speed when the speed is changed during the position control of speed-position switching control or position-speed switching control, the operation will be carried out at the speed that could be changed.

5) If the speed changed by the "override function" is greater than the "

Pr.8

Speed limit value", a warning "Speed limit value over (warning code: 501)"

will occur and the speed will be controlled at the " The " Md.39 Speed limit flag" will turn ON.

Pr.8

Speed limit value".

Da. 8 Command speed	50
Cd. 13 Positioning operation
	100		1		50		150	100	200
speed override
Md. 22 Feedrate	50	1		25		75		50	75
V									Not enough remaining
								Not affected by the override value
								during deceleration	distance could be secured,
									so operation is carried out
									at an increased speed.

t

Fig. 12.28 Override function operation

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