10.3 Using an Absolute Encoder
10-13
10
The Zero Point Offset (setting parameter OL
48) is always valid for a finite length axis. If the machine coor-
dinate system zero point is changed during machine operation, the current position may become inaccurate.
The meaning of setting parameter OL
48 will differ for a finite length axis and infinite length axis.
• Finite Length Axis
Set OL
48 to the difference between IL
48 and OL
10 (IL
48 – OL
10) to make the cur-
rent position of the machine coordinate system the zero position.
IL
10 = 10,000 and OL
48 = 100
Setting the current position of the machine coordinate system to 0.
100
−
10000 =
−
9900 Set OL
48 to
−
9,900
IL
10:
Target Position (CPOS)
(3) Setting the Zero Point for a Finite Length Axis
Set the zero point after initializing the absolute encoder to set the zero point of the machine coordinate system
and to establish the machine coordinate system.
The following illustration shows the procedure for setting the zero point for a finite length axis.
* 1. The OL
48 value must be saved when it is set.
* 2. See the information on the next page for more details on saving the OL
48 value.
* 3. Execute with the ZSET command.
EXAMPLE
Repeat for every axis.
Start
Servo ON
STEP to move to the
zero point.
OL
48 = OL
48 - IL
10
Save OL
48
*2
End
JOG to move close to
the zero point.
YES
NO
Set the zero point.
* 3
* 1
Has the setting for the required
axis been completed?