Rockwell Automation 1775-MX_S4A,D17756.3.1 User Manual PLC-3 BACKUP CONC(OR.DU1 - Manual (Page 30)

Installing a Backup System
Chapter 2
2-15
There are four I/O serial communication channels per scanner. Depending
on your system architecture, you can use one or more of them for:
I/O communication
Peer-to-peer communication
Backup communication
To do this, you connect I/O cables to the terminal swing arm and configure
each channel for the type of communication desired. You configure I/O
channels by using LIST.
Figure 2.13 shows how to identify the terminals on a terminal swing arm.
Figure 2.13
I/O Cables Terminate at Terminal Swing Arms
Line 1
Shield
Line 2
Line 1
Shield
Line 2
Channel
No. 4
Channel
No. 2
Line 1
Shield
Line 2
Line 1
Shield
Line 2
Channel
No. 3
Channel
No. 1
10044
Important: For 1775-S4A or -SR scanner modules used as the number
one scanner, when using I/O channel 5 to communicate with a peripheral
device, I/O channel 4 of the number one scanner module cannot be used.
Do not make any connections to I/O channel 4.
Connecting the I/O
Channel Wiring