Mitsubishi Electronics QD75P, QD75D user manual 3 QD75 sub functions and common functions

3 SPECIFICATIONS AND FUNCTIONS

3.2.3QD75 sub functions and common functions

Sub functions

MELSEC-Q

The functions that assist positioning control using the QD75 are described below. (Refer to Section 2 for details on each function.

Sub function

Details

Reference

section

This function retries the machine OPR with the upper/lower

Functions

OPR retry function

limit switches during machine OPR. This allows machine OPR

12.2.1

to be carried out even if the axis is not returned to before the

characteristic

near-point dog with JOG operation, etc.

to machine

After returning to the machine OP, this function compensates

OPR

OP shift function

the position by the designated distance from the machine OP

12.2.2

position and sets that position as the OP address.

Backlash compensation

This function compensates the mechanical backlash. Feed

pulses equivalent to the set backlash amount are output each

12.3.1

function

time the movement direction changes.

By setting the movement amount per pulse, this function can

Functions that

freely change the machine movement amount per commanded

pulse.

compensate

Electronic gear function

12.3.2

When the movement amount per pulse is set, a flexible

control

positioning system that matches the machine system can be

structured.

This function suppresses the machine vibration when the

Near pass function

1

speed changes during continuous path control in the

12.3.3

interpolation control.

If the command speed exceeds "

Speed limit value"

Pr.8

Speed limit function

during control, this function limits the commanded speed to

12.4.1

within the "

Speed limit value" setting range.

Pr.8

If the torque generated by the servomotor exceeds "

Pr.17

Functions that

Torque limit function

2

Torque limit setting value" during control, this function limits the

12.4.2

limit control

generated torque to within the "

Pr.17

Torque limit setting

value" setting range.

Software stroke limit

If a command outside of the upper/lower limit stroke limit

setting range, set in the parameters, is issued, this function will

12.4.3

function

not execute positioning for that command.

Hardware stroke limit

This function carries out deceleration stop with the limit switch

12.4.4

function

connected to the QD75 external device connector.

This function changes the speed during positioning.

Set the new speed in the speed change buffer memory

Speed change function

(

New speed value), and change the speed with the

12.5.1

Cd.14

Speed change request (

).

Cd.15

Functions that

This function changes the speed within a percentage of 1 to

change control

details

Override function

300% during positioning. This is executed using "

Cd.13

12.5.2

Positioning operation speed override".

Acceleration/deceleration

This function changes the acceleration/deceleration time during

12.5.3

time change function

speed change.

Torque change function

This function changes the "torque limit value" during control.

12.5.4

Absolute position restoration function

3

This function restores the absolute position of designated axis.

12.6

1: The near pass function is featured as standard and is valid only for position control. It cannot be set to be invalid with parameters.

2: Using "Torque limit function" requires a "D/A conversion module" and a "drive unit capable of torque limit command with analog voltage". 3: Using "Absolute position restoration function" requires a "16-point input module", a "16-point output module", and a "drive unit that can

construct absolute position detection system".

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