Omron NX-EC0112, User Manual

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7 SSI Input Units
7 - 4 NX-series Position Interface Units User’s Manual (W524)
7-2 System Configuration
The following figure shows the system configuration of an SSI Input Unit.
Precautions for Correct Use
SSI Input Units provide only I/O interface functions for a synchronized serial interface. For
errors related to communications data, checks are made for communications errors and parity
errors (if there is parity), but error correction and other communications protocol processing are
not supported.
Therefore, you must check for data errors and perform any error processing on input data, such
as the present value or status data, in the Controller.
SSI Input Units have an auxiliary function that you can use to separate error data based on the
amount of change in the present value since the last value. Refer to
7-9-8 Error Data Detection
on page 7-55 for information on this auxiliary function.
Use this auxiliary function or other methods to handle communications data errors when you
use SSI Input Units together with the MC Control Module in an NJ/NX-series Controller.
Symbol Description
(A) Support Software (Sysmac Studio)
(B) Connection to the peripheral USB port or built-in EtherNet I/P port on an NJ/NX-series CPU Unit
(C) EtherCAT master (NJ/NX-series CPU Unit)
(D) EtherCAT communications cable
(E) EtherCAT Coupler Unit
(F) SSI Input Unit
(G)
SSI encoder
*1
*1. The SSI encoder is supplied with 24-VDC power from the SSI Input Unit.
(H) I/O power supply
(E)
(A)
(B)
(D)
(C)
(F)
(H)
(G)