beautypg.com

Melsec-q, 12 control sub functions – MITSUBISHI ELECTRIC Mitsubishi Programmable Logic Controller QD75D User Manual

Page 512

background image

12 - 36

MELSEC-Q

12 CONTROL SUB FUNCTIONS

(4) When the speed is changed by setting "

Cd.14

New speed value" to "0",

the operation is carried out as follows.

A deceleration stop is carried out, and the speed change 0 flag

(

Md.31

Status: b10) turns ON.

(During interpolation control, the speed change 0 flag on the reference axis

side turns ON.)

The axis stops, but "

Md.26

Axis operation status" does not change, and

the BUSY signal remains ON. (If a stop signal is input, the BUSY signal

will turn OFF, and "

Md.26

Axis operation status" will change to

"stopped".)

In this case, setting the "

Cd.14

New speed value" to a value besides "0"

will turn OFF the speed change 0 flag (

Md.31

Status: b10), and enable

continued operation.

Md. 31 status: b10

Positioning start signal

BUSY signal

Cd. 14 New speed value

Cd. 15 Speed change request

Positioning operation

1000

0

ON

OFF

ON

OFF

ON

OFF

ON

OFF

Speed change 0 flag

[Y10, Y11, Y12, Y13]

[XC,XD,XE,XF]

Fig. 12.25 Speed change at new speed value "0"

(5) A warning "Deceleration/stop speed change (warning code: 500)" occurs

and the speed cannot be changed in the following cases.

During deceleration by a stop command

During automatic deceleration during positioning control

(6) A warning "Speed limit value over (warning code: 501)" occurs and the

speed is controlled at the " Pr.8 Speed limit value" when the value set in

"

Cd.14

New speed value" is equal to or larger than the " Pr.8 Speed limit

value".

(7) When the speed is changed during interpolation control, the required speed

is set in the reference axis.

(8) When carrying out consecutive speed changes, be sure there is an interval

between the speed changes of 100ms or more.

(If the interval between speed changes is short, the QD75 will not be able to

track, and it may become impossible to carry out commands correctly.)

(9) When a speed change is requested simultaneously for multiple axes,

change the speed in the ascending axis number order.

(10) Speed change cannot be carried out during the machine OPR. A request

for speed change is ignored.

(11) When deceleration is started by the speed change function, the deceleration

start flag does not turn ON.