9MAJOR POSITIONING CONTROL

POINTS

MELSEC-Q

The machine recognizes the presence of a command speed change request when the data is

written to "

Cd.25

Position-speed switching control speed change register" with the sequence

program.

The new command speed is validated after execution of the position-speed switching control before the input of the position-speed switching signal.

The command speed change can be enabled/disabled with the interlock function in speed control

using the "position-speed switching latch flag" (

Md.31

Status: b5) of the axis monitor area.

Restrictions

(1)An axis error (error code: 516) will occur and the operation cannot start if "continuous positioning control" or "continuous path control" is set in

" Da.1 Operation pattern".

(2)"Position-speed switching control" cannot be set in "

Da.2

Control system" of

the positioning data when "continuous path control" has been set in

"

Da.1

Operation pattern" of the immediately prior positioning data. (For

example, if the operation pattern of positioning data No. 1 is "continuous path control", "position-speed switching control" cannot be set in positioning data No. 2.) An axis error (error code: 516) will occur and the machine will carry out a deceleration stop if this type of setting is carried out.

(3) The software stroke limit range is only checked during speed control if the "1:

Update current feed value" is set in "

Pr.21

Current feed value during speed

control".

The software stroke limit range is not checked when the control unit is set to "degree".

(4)An error (error code: 507 or 508) will occur and the operation cannot start if the start point address or end point address for position control exceeds the software stroke limit range.

(5)Deceleration stop will be carried out if the position-speed switching signal is not input before the machine is moved by a specified movement amount. When the position-speed switching signal is input during automatic deceleration by positioning control, acceleration is carried out again to the command speed to continue speed control.

When the position-speed switching signal is input during deceleration to a stop with the stop signal, the control is switched to the speed control to stop the machine.

Restart is carried out by speed control using the restart command.

(6)A warning (warning code: 501) will occur and control is continued by

"

Pr.8

Speed limit value" if a new speed exceeds "

Pr.8

Speed limit value" at

the time of change of the command speed.

(7)If the value set in " Da.6 Positioning address/movement amount" is negative, an error (error code: 530) will occur.

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Image 403
Mitsubishi Electronics QD75D, QD75P user manual Status b5 of the axis monitor area, Speed limit value if a new speed exceeds