6.9
Absolute Linear Encoders
The absolute linear encoder records the current position of the stop position even when the power
supply is OFF.
With a system that uses an absolute linear encoder, the host controller can monitor the current
position. Therefore, it is not necessary to perform an origin return operation when the power supply to
the system is turned ON.
There are three types of linear encoders for Linear Servomotors. The usage of the linear encoder is
specified in Pn002 = n.
Refer to the following section for linear encoder models.
Feedback Resolution of Linear Encoder
•
Parameter Settings When Using an Incremental Linear Encoder
Parameter
n.
0
(default setting)
Pn002
n.
1
•
Parameter Settings When Using an Absolute Linear Encoder
Parameter
n.
0
(default setting)
Pn002
n.
1
6.9.1
Connecting an Absolute Linear Encoder
You can get the position data from the absolute linear encoder with MECHATROLINK
communications. Therefore, it is not necessary to wire the PAO, PBO, and PCO (Encoder Divided
Pulse Output) signals.
If they need to be wired, refer to the following section.
4.4.3
Wiring the SERVOPACK to the Encoder
4.5.3
I/O Signal Wiring Examples
6.9.2
Structure of the Position Data of the Absolute Linear
Encoder
The position data of the absolute linear encoder is the distance (number of pulses) from the origin of
the absolute linear encoder.
The position data is signed 36-bit data.
5
±
Upper 16 bit (with ign)
When the SERVOPACK sends the position data, it sends the upper 16-bit data (with sign) separately
from the lower 20-bit data.
X
.
on page 5-45
Use the encoder as an incremental linear encoder.
Use the encoder as an incremental linear encoder.
Use the encoder as an absolute linear encoder.
Use the encoder as an incremental linear encoder.
on page 4-27
on page 4-37
6.9.1 Connecting an Absolute Linear Encoder
Meaning
Meaning
20 19
Lower 20 bit
6.9 Absolute Linear Encoders
When Enabled Classification
After restart
Setup
When Enabled Classification
After restart
Setup
0
6
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