Rockwell Automation 1747-ACNR15 ControlNet Adapter Module User Manual - Manual (Page 63)

Publication 1747-UM003A-EN-P
4-35
NOTE
There is a 2-word offset for input data for rack connections.
Therefore, for this example, the input data for the input
module in slot 1 of the remote 1747-ACN15 chassis is
written to I:3.3 in the SLC processor’s input image.
The starting input address configured in RSNetWorx for
this rack connection was I:3.1, but I:3.1 and I:3.2 are used
for status information. Therefore, the actual input data
begins after the 2 words of status information. I:3.4 is not
used in this example because an output module resides in
slot 2.
Also, note that there is no offset for the outputs in a rack
connection. O:3.2 is the output image word written to the
output module located in slot 2 of the 1747-ACN15
chassis. O:3.1 is not used because an input module resides
in slot 1. In addition, no offset applies to module
connections at all.