Rockwell Automation 1747-ACNR15 ControlNet Adapter Module User Manual - Manual (Page 25)

Publication 1747-UM003A-EN-P
Planning to Use Your ControlNet Adapter Module 3-5
If we change the default number of words for the input and output values (to 4
and 4) when inserting the connection to the 1747-ACNR15 adapter, Node 2
will produce 4 input words over ControlNet and Node 1 will consume and
place those words at addresses I:e.1-4, where the slot 1 inputs correspond to
I:e.3 and the slot 2 inputs correspond to I:e.4. In addition, Node 1 will produce
4 output words over ControlNet originating from addresses O:e.1-4 and Node
2 will consume them. A total of 8 words (4 input and 4 output) are transmitted
on ControlNet.
Consider the following:
•
The 1747-SCNR has 31 input words and 31 output words available for
rack connections to 1747-ACNR15 adapters.
•
Each 1747-ACNR15 adapter requires 2 input words for status in addition
to the input words assigned to the slots.
•
Adjust the rack connection size to match the maximum density I/O
module:
– Discrete 8-bit Exclusive Owner for 4 and 8-point modules
– Discrete 16-bit Exclusive Owner for 16-point modules
– Discrete 32-bit Exclusive Owner for 32-point modules.
Module Keying
Missing or misplaced modules are detected if the module in question is
configured with RSNetWorx as an individual module connection and
“compatible module” is selected for electronic keying. If a module connection
is attempted to a module which is a missing or misplaced module, the
connection will fail. The green OK LED on the initiating scanner will flash
and the module will display “I/O” with a partially filled bar indicating all
connections are not established, as shown below.
NOTE
To optimize ControlNet network bandwidth, place the
devices in the following order (left to right on the chassis):
•
1747-ACNR15 adapter
•
Discrete input modules
•
Discrete output modules
•
Any intelligent and/or analog I/O modules that you want
to establish individual module connections to
I/O