YASKAWA MP Series User Manual

9.3 Absolute Position Detection for Finite Length Axes
9.3.2 Setting the Zero Point for a Finite Length Axis
9-9
Absolute Position Detection
9.3.2 Setting the Zero Point for a Finite Length Axis
This section describes the procedure for setting the zero point (i.e., the absolute zero point or the zero point of the
machine coordinate system) for a finite length axis. It also describes the procedures for storing the zero point offset.
( 1 ) Calculating the Zero Point of the Machine Coordinate System
The Machine Controller calculates the axis position (i.e., current position for the machine coordinate system) as fol-
lows 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 Position in Machine Coordinate System Off-
set (setting parameter OL

48)
To set the current position of the machine coordinate system as the zero position, 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 coordinate system and to
create the machine coordinate system. The following illustration shows the procedure 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 Position in Machine Coordi-
nate System 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.
STEP to move to the zero point.
Set OL48 to OL48 - IL10.
Use the ZSET command to set the zero point.
Has the setting for the required axis been completed?

YASKAWA MP Series Specifications

General

Brand	YASKAWA
Model	MP Series
Category	Controller
Language	English