3 PARAMETERS FOR POSITIONING CONTROL
3.3 Fixed Parameters
169
3
Unit Setting
Set the unit used for defining positioning operations.
Choose from the following units depending on the type of the control target: mm, inch, degree, or pulse.
Ex.
Different units (mm, inch, degree, and pulse) are applicable to different systems:
When you change the unit, note that the values of other parameters and data will not be changed automatically. After
changing the unit, check if the parameter and data values are within the allowable range.
Number of pulses per rotation/Travel value per rotation
The "Electronic gear function" adjusts the actual machine movement amount and number of pulse output to servo amplifier
according to the parameter set in the Motion CPU.
It is defined by the "Number of pulses per rotation" and "Travel value per revolution".
• The mechanical system error of the command travel value and real travel value is rectified by adjustment
the "electronic gear".
• The value of less than 1 pulse that cannot be execute an output when the machine travels is incremented in
the Motion CPU, and a total incremented output is performed when the total incremented value becomes
more than 1 pulse.
• The total incremented value of less than 1 pulse that cannot be execute an output is cleared and it is
referred to as "0" at the home position return completion, current value change completion, and fixed-pitch
feed control start. (When the total incremented value is cleared, the error occurs to the feed machine value
only a part to have been cleared.)
Number of pulses/travel value per rotation
Number of pulses (AP)/travel value (AL) per rotation is an item which determines how many rotations (number of pulses per
rotation) of the servomotor in order to make it a machine as the travel value ordered by the program.
The position control toward the servomotor is controlled with the number of feedback pulses of the encoder connected to the
servomotor in the servo amplifier.
The control content of the Motion CPU is shown below.
Unit
System
mm, inch
X-Y table, conveyor (Select mm or inch depending on the machine specifications.)
degree
Rotating body (360 degrees/rotation)
pulse
X-Y table, conveyor
Motion CPU
AP
AL
Command
value
Control
units
pulse
pulse
Machine
Reduction gear
Servo
amplifier
M
ENC
pulse
Feedback pulse
Summary of Contents for MELSEC iQ-R16MTCPU
Page 2: ......
Page 477: ...APPENDICES Appendix 1 Processing Times of the Motion CPU 475 A MEMO ...
Page 481: ......