YASKAWA JEPMC-MP2300-Y Series

9
Absolute Position Detection
9.3.2
Setting the Zero Point for a Finite Length Axis
9-10
( 1 ) Calculating the Zero Point of the Machine Coordinate System
The MP2300 calculates the axis position (i.e., current position for the machine coordinate system) as
follows when power is turned ON if an absolute encoder is used for positioning.
Current position for the machine coordinate system (monitoring parameter IL

10
*1
or
IL

16
*1
) = Encoder position when servo power is turned ON
*2
+ Zero Point Offset (setting
parameter OL

48)
To make the current position of the machine coordinate system the zero position, set OL

48
(encoder position when servo power turns ON) to a negative value. In other words, set OL

48 to
the difference between OL

48 and IL

10 (or IL

16).
* 1. Use IL

10 to select a positive value for the reference position for the machine coordinates, and
use IL

16 to make the current position of the machine coordinates into a positive position.
* 2. The encoder position when servo power is turned ON is as follows: Multiturn data
×
Number of
encoder pulses + initial increment pulses. Refer to your SERVOPACK manual for information on
the initial increment pulses.
Example: IL

10 = 10,000 and OL

48 = 100
Set the encoder position when servo power is turned ON to a negative value as shown below.
OL

48
－
IL

10 = 100
－
10000
=
－
9900
Set OL

48 to -9900 to make the current position in the machine coordinate system the zero point.
( 2 ) Setting the Zero Point of the Machine Coordinate System
Set the zero point after initializing the absolute encoder to set the zero point of the machine coordi-
nate system and to create the machine coordinate system. The following illustration shows the proce-
dure for setting the zero point for a finite length axis.

OL

48 is always valid for a finite length axis. Do not change the Zero Point
Offset (OL

48) during the operation of a machine with a finite length axis.
Otherwise the machine may be damaged or an accident may occur.
CAUTION
Repeat for every axis.
Start
End
YES
NO
Servo ON
JOG to move close to the zero point.
JSTEP to move to the zero point.
Set OL48 OL48 - IL10.
Use the ZSET command to set the zero point.
Has the setting for the required axis been completed?