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12 CONTROL AUXILIARY FUNCTIONS
12.1 Outline of auxiliary functions
"Auxiliary functions" are functions that compensate, limit, add functions, etc., to the
control when the main functions are executed. These auxiliary functions are executed
by parameter settings, commands from the AD75 software package, auxiliary function
sequence programs, etc.
12.1.1 Outline of auxiliary functions
The following table shows the types of auxiliary functions available.
Auxiliary function Details
Functions
characteristic
to machine
zero point
return
Zero point return retry
function
This function retries the machine zero point return with the upper/lower limit
switches during machine zero point return. This allows machine zero point
return to be carried out even if the axis is not returned to before the near-
point dog with JOG operation, etc.
Zero point shift function
After returning to the machine zero point, this function offsets the position by
the designated distance from the machine zero point position and sets that
position as the zero point address.
Functions that
compensate
control
Backlash compensation
function
This function compensates the mechanical backlash. Feed pulses equivalent
to the set backlash amount are output each time the movement direction
changes.
Electronic gear function
By setting the movement amount per pulse, this function can freely change
the machine movement amount per commanded pulse.
When the movement amount per pulse is set, a flexible positioning system
that matches the machine system can be structured.
Near pass mode function
This function suppresses the machine vibration when the speed changes
during continuous path control in the interpolation control.
Functions that
limit control
Speed limit function
If the command speed exceeds "
Pr.7
Speed limit value" during control,
this function limits the commanded speed to within the "
Pr.7
Speed limit
value" setting range.
Torque limit function *
1
If the torque generated by the servomotor exceeds "
Pr.18
Torque limit
setting value" during control, this function limits the generated torque to
within the "
Pr.18
Torque limit setting value" setting range.
Software stroke limit
function
If a command outside of the upper/lower limit stroke limit setting range, set in
the parameters, is issued, this function will not execute positioning for that
command.
Hardware stroke limit
function
This function carries out deceleration stop with the limit switch connected to
the D75P2 external device connection connector.
Functions that
change control
details
Speed change function
This function changes the speed during positioning.
Set the changed speed in the speed change buffer memory "New speed
value (RWwm+4 to 5, RWwm+12 to 13)", and change the speed with the
speed change request "Speed change request (RY(n+2)7, RY(n+4)7)".
Override function
This function changes the speed within a percentage of 1 to 300% during
positioning. This is executed using "Positioning operation speed override
(RWwm+1, RWwm+9)".
Acceleration/deceleration
time change function
This function changes the acceleration/deceleration time during speed
change.
Torque change function This function changes the "torque limit value" during control.
*
1
To carry out "torque limit", the "D/A conversion module" and a "drive unit capable of the torque limit command with an
analog voltage" must be prepared.