Designing a remote i/o link, Designing a remote i/o link -4 – Rockwell Automation 1785-Lxxx Enhanced and Ethernet PLC-5 Programmable Controllers User Manual
Page 76

Publication 1785-UM012D-EN-P - July 2005
6-4 Communicating with Remote I/O
Follow these steps for setting up a remote I/O system:
Designing a Remote I/O
Link
Designing a remote I/O link requires applying:
•
remote I/O link design guidelines
•
cable design guidelines
Link Design Guidelines
For this Step
See
1.configure the remote I/O adapter devices
the device’s user manual
2.layout and connect the remote I/O link cable
•
•
chapter 3 for cable routing information
•
your controller’s installation information
(For enhanced PLC-5 controllers, see publication
1785-IN062; for Ethernet PLC-5 controllers
publication 1785-IN063)
3.configure the scanner channel
TIP
Keep these rules in mind as you design remote I/O links:
•
All devices connected to a remote I/O link must
communicate using the same communication rate,
either 57.6, 115.2, or 230.4 kbps. Choose a rate that all
devices support.
•
Two or more channels of the same controller operating
in scanner mode cannot scan the same partial or full
rack address. Assign unique partial and full racks to
each channel used in remote I/O scanner mode.
•
You can split rack addresses between scanner channels;
however, issues arise when performing block-data
transfer. See page 6-15.
•
A scan list can have a maximum of 16 rack numbers or
a maximum of 32 physical devices connected to it using
82-
Ω
termination resistors. See page 6-9 for more
information about scan lists.