Installation guide

44 Elements of Network Planning
890 USE 100 00
2.1 An Overview of Network Planning
You should consider the following factors in the layout of your Modbus
Plus network:
V You can design your control system from a wide range of controller
performance features. You can choose your system layout from
many variations in distributed control, local and remote
input/output systems, and user interfaces. A major factor
determining your Modbus Plus networking requirement will be your
definition of the types, quantities, and site locations of the
programmable control components required for your application.
V Planning of your overall programmable control system is beyond the
scope of this document. For further information refer to the books
for Modicon controllers listed in the Related Publications section in
the front of this book.
V If you intend that your network will primarily service I/O processes,
you should refer to the Modbus Plus Network I/O Servicing Guide
for further information to assist you in your design. That book
gives guidelines and performance estimates for those kinds of
applications.
V Typically, you will be defining the site locations of your system
components according to your process flow and work cell layout.
Your network design should support your requirements for the
transfer of information between those processes. Your design
should also accommodate any host or supervisory computer involved
in the job of monitoring the process activity, loading configuration
and recipe files, retrieving statistics, and providing reports.
V Your network layout should provide ready access for debugging your
application and for future maintenance. Plan to include extra
inline taps and drop cables at convenient points. You will be able to
use them for connecting a device to monitor the network activity
and collect statistics, without having to disconnect some active
device. This service access will also allow you to temporarily
connect, test, and debug future devices as you expand your
networking application.
Your planning should include preparation of documents that describe
the network plan. These should support ordering of materials,
installation of the network, and future maintenance. Worksheet
examples are provided in this guidebook. You’ll also find blank