5.2.6 Position Management Method For Each Machine Operation Type - YASKAWA SVC User Manual

5.2 Absolute Encoders

5.2.6 Position Management Method for Each Machine Operation Type

5.2.6 Position Management Method for Each Machine Opera-
tion Type
Machine operation methods can be broadly classified into the following two types.
• Finite-length Operation
Finite-length operation is machine operation that performs round-trip operations within a
defined travel range.
This method is used when the travel range is within the absolute encoder's counting range.
No special management of the current value is required.
• Infinite-length Operation
Infinite-length operation is machine operation where movement is performed in only one
direction, such as for a conveyor belt.
Because the travel range exceeds the absolute encoder's counting range, special position
management is required, such as resetting the current value at a specific count value and
then starting the count again.
Finite-length Operation
Finite-length operation is machine operation that performs round-trip operations within a
defined travel range. This section describes parameter settings required with finite-length oper-
ation, precautions for parameter settings, setting the origin, and precautions for when the
power supply is turned OFF and ON.
 Parameter Settings
This section describes the parameter settings for each axis when performing finite-length oper-
ation.
 Fixed Parameter Settings Required for Finite Axis Position Management
Set bit 0 (Axis Selection) in fixed parameter No. 1 to 0 (Finite-length axis) to use the axis as a
finite-length axis.
No.
1
*
When a finite-length axis is selected, the setting of bit 9 is ignored.
 Fixed Parameter Settings Required for an Absolute Encoder System
The fixed parameters that must be set for an absolute encoder system are listed in the follow-
ing table.
No.
4
30
36
38
*
N is the number of encoder bits.
5-26
Bit Name
0 Axis Selection
Simple Absolute Infinite Axis Posi-
9
tion Management
Name
Reference Unit Selection
Encoder Selection
Number of Pulses Per Motor
Rotation
Maximum Number of Absolute
Encoder Rotations
Setting (Meaning)
0 (Finite-length
axis)
0* (Disabled)
Setting
Setting
Unit
0: pulse
1: mm
2: deg –
3: inch
4: μm
1: Absolute encoder –
N *
pulse
2
Rota-
31
0 to 2 - 1
tions
Reference

Function Selection Flags 1 on
page 3-28
Reference

Reference Unit Selection on
page 3-31

Encoder Selection on page 3-
33

Number of Pulses Per Motor
Rotation on page 5-27

Maximum Number of Abso-
lute Encoder Rotations on page
3-35