Mitsubishi Electric MELSEC-L LD75D, User Manual

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APPENDICES
A
Appendix
8
ME
LSE
C
E
xplanat
ion
of
Pos
itioning T
e
rm
s
POSITION LOOP MODE
This is one servo control mode used in positioning. It is a mode for carrying out position control. The other servo
control modes are the speed loop mode for carrying out speed control, and the torque loop mode for carrying out
torque control (current control).
POSITIONING
Accurately moving the machine from a point to a determined point. The distance, direction, speed, etc., for that
movement are designated by the user.
Positioning is used in operations such as cutting sheets, drilling holes in plates, mounting parts on a PCB, and
welding. Positioning is also used with robots.
POSITIONING DATA
This is data for the user to carry out positioning. The No. of points to which positioning is carried out (the No. of
addresses) is designated by the user. In the LD75, these are 600 points. As a principle, positioning is executed in
the order of the data Nos.
POSITIONING COMPLETE Refer to the term "OPERATION PATTERN".
POSITIONING COMPLETE SIGNAL
This is a signal that occurs when the positioning is complete. A timer set beforehand starts when this signal is
output, and the machine movement stops for that time.
When this signal turns ON, the positioning start signal turns OFF.
POSITIONING START
This refers the act of designating a target data No. and starting the positioning.
The operation after the positioning is complete for that data No. is determined by the data No.'s positioning
pattern.
POSITIONING CONTINUED Refer to the term "OPERATION PATTERN".
POSITIONING PARAMETER
This is basic data for carrying out positioning control. Types of data include control unit, movement amount per
pulse, speed limit value, upper/lower stroke limit values, acceleration/deceleration time, positioning system, etc.
Parameters have an initial value, so that value is changed to match the control conditions.
POSITION DETECTION MODULE
This is an abridged version of positioning. There are two types on MELSEC, the A1S62LS. This module has
positioning and limit switch functions, and can use a total of 16 channels. The following drawing shows an
example for 5 channels. A resolver is used in the positioning detection.
POSITION CONTROL
This is mainly the control of position and dimension, such as in fixed-feed, positioning, numerical control, etc.
This is always controlled with feed pulses. There is also speed control.
Drive units may differ, even when the same motor is used.
Term Description
PLG
M
Servo amplifier
Pulse train
Droop pulses
Position
control
Speed
control
Current
control
Inverter
Current feedback
Speed feedback
Position feedback Interface
Servomotor
Dwell time
Positioning complete
signal
Positioning Different type of work
Time
ON
ON
N O N O
ON
ON
0 4095
Limit switch LS1
Positioning High speed
Positioning Low speed
Limit switch LS3
Limit switch LS2