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6 SERVO MOTOR DRIVING
6.2 Point table mode (pt)
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Operation
Selecting the point table with "Target point table" and switching on "Controlword bit 4 (New set-point)" starts positioning to the
position data at the set speed, acceleration time constant and deceleration time constant.
Incremental value command method
• The incremental value command method ([Pr. PT01] = _ _ _ 1) is not available in the absolute position
detection system. When using the absolute position detection system, select the absolute value command
method ([Pr. PT01] = _ _ _ 0).
• When the servo is turned off with the incremental value command method ([Pr. PT01] = _ _ _ 1), the home
position is erased. Execute home position return again.
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Point table
Set the point table values using MR Configurator2 or "Point table 001 to 255". Set the position data, servo motor speed,
acceleration time constant, deceleration time constant, dwell time, and auxiliary function to the point table.
When you set a value outside the setting range to the point table, the setting value will be clamped with the maximum or
minimum value. If the value becomes out of the range because of the changes in the command unit or the connected servo
motor, [AL. 37] will occur.
*1 When the unit of the position data is
m or inch, the location of the decimal point is changed according to the STM setting. The setting
range of the position data in degrees is 000.000 to 999.999.
*2 In the linear servo motor control mode, the unit is mm/s.
Item
Object to be used
Setting
Point table mode (pt) selection
Modes of operation
Set "-101".
Point table selection
Target point table
Set the point table No. to use.
Start
Controlword
Switch on "Controlword bit 4 (New set-point)".
Item
Setting range
Unit
Description
Position data
0 to 999999
×10
STM
μ
m
×10
(STM-4)
inch
×10
-3
degree
pulse
Set the travel distance.
The unit can be changed by [Pr. PT03] (Feed length multiplication).
Servo motor speed
0 to permissible speed
0.01 r/min
0.01 mm/s
Set the command speed of the servo motor for execution of positioning.
The setting value must be equal to or less than the instantaneous
permissible speed of the servo motor used.
The fractional portion will be rounded down.
Acceleration time
constant
0 to 20000
ms
Set a time for the servo motor to reach the rated speed.
Deceleration time
constant
0 to 20000
ms
Set a time for the servo motor to stop from the rated speed.
Dwell
0 to 20000
ms
Set the dwell.
To disable the dwell, set "0" to the auxiliary function.
To perform a continuous operation, set "1", "8" or "9" to the auxiliary function
and "0" to the dwell.
When the dwell is set, a positioning of the next point table will be started
after the positioning of the selected data is completed, and the set dwell has
elapsed.
Auxiliary function
0, 1, 8, or 9
Set the auxiliary function.
0: Automatic operation for a selected point table is performed.
1: Automatic operation for the next point table is performed.
8: Automatic operation for a point table selected at start-up is performed.
9: Automatic operation for point table No. 1 is performed.
Setting "1" to point table No. 255 results in an error.
Refer to the following for details.
