Omron NX-EC0112, User Manual

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7 SSI Input Units
7 - 36 NX-series Position Interface Units User’s Manual (W524)
7-8 Setting Methods
This section describes the setting methods for the SSI Input Units.
You can use an SSI Input Unit as an encoder axis input device if you also use the MC Function Module.
This section describes the settings for using an NJ/NX-series Controller and the MC Function Module to
control SSI Input Units.
For details on the functions of the MC Function Module, refer to the NJ/NX-series CPU Unit Motion
Control User’s Manual (Cat. No. W507).
Precautions for Correct Use
To assign a Position Interface Unit to an axis in the MC Function Module, you must assign NX
Unit I/O Data Active Status

in the EtherCAT Coupler Unit. Replace “

” with 15, 31,
63, or 125 according to the highest NX Unit number of the EtherCAT Coupler Units. Refer to the
N
X-series EtherCAT Coupler Unit User’s Manual (Cat. No. W519) for details.
SSI Input Units are mounted after an EtherCAT Coupler Unit to build an NX Unit Slave Terminal. The
Slave Terminal is connected through EtherCAT communications.
Refer to the NX-series EtherCAT Coupler Unit User’s Manual (Cat. No. W519) for information on how to
build NX Unit systems.
Refer to 7-5 Terminal Block Arrangement on page 7-10 for information on wiring SSI Input Units to
external devices, such as SSI encoders.
This section describes the minimum parameter settings that are required to use SSI Input Units with the
MC Function Module.
Refer to 7-9-1 Parameters on page 7-38 for information on SSI Input Unit parameters.
You can set SSI Input Unit parameters for a variety of SSI encoder communications data formats, tim-
ings, coding methods, and other settings.
Set the parameters based on the communications specifications of the connected SSI encoder.
Refer to 7-9-2 SSI Data Settings on page 7-40 for information on SSI communications settings.
Use the Encoder Count Direction parameter to specify the incrementing/decrementing direction in the
Unit in comparison to the incrementing/decrementing direction of the SSI Encoder.
You can reverse the count direction from the Unit for SSI encoders that provide the absolute position in
the communications data.
The default setting for the SSI Input Unit is 0 (Not to invert the sign).
Refer to 7-9-4 Encoder Count Direction on page 7-50 for information on setting the count direction.
7-8-1 Building and Wiring the System
7-8-2 Setting Examples
Setting Up SSI Communications
Count Direction Setting