6 Incremental Encoder Input Units
6 - 24
NX-series Position Interface Units User’s Manual (W524)
Precautions for Correct Use
• If you use a Position Interface Unit and EtherCAT Coupler Unit together and you use
Free-Run refreshing, set the task period to a value that is greater than or equal to the refresh
cycle of the Position Interface Unit.
• If you use synchronous I/O refreshing or task period prioritized refreshing, set the task period
to a value within the specified refresh cycle range of the Position Interface Unit.
• If you set task period prioritized refreshing for the NX-EC022 and operate at 125 μs, a
WDT error will occur in the Incremental Encoder Input Unit and the TS indicator will light red.
An NX Unit Minor Fault error event will occur in the Communications Coupler Unit at the
same time.
For the communications cycle specifications of the built-in EtherCAT port on an NJ/NX-series CPU
Unit, refer to the NJ/NX-series CPU Unit Built-in EtherCAT Port User's Manual (Cat. No. W505). For the
communications cycle specifications of the EtherCAT Coupler Unit, refer to the NX-series EtherCAT
Coupler Unit User’s Manual (Cat. No. W519-E1-05 or later).
Use Free-Run refreshing to exchange data without worrying about the timing of when the Incremental
Encoder Input Unit obtains the position data.
Position data is obtained according to the Unit’s cycle, regardless of the Controller’s processing inter-
val.
Data is exchanged with the Controller based on the I/O refreshing timing of the Controller.
The data that is exchanged is the position data that was obtained in the last Unit cycle when I/O
refreshing is performed.
Precautions for Correct Use
If you use a Position Interface Unit and EtherCAT Coupler Unit together and you use Free-Run
refreshing, set the task period to a value that is greater than or equal to the refresh cycle of the
Position Interface Unit.
The refresh cycle is always 125 μs for unit version 1.2 or later.
The refresh cycle is always 250 μs for unit version 1.1 or earlier.
6-6-2 Free-Run Refreshing
I/O refreshing
Data
processing
I/O refreshing
Data
processing
Controller
Incremental Encoder
Input Unit
Controller cycle
time
Position data
Cycle to obtain position data and to execute commands