CPC MultiFlex PAK, User Manual

Page: 15 / 52

Wiring Types The I/O Network • 7
3 The I/O Network
All MultiFlex PAK boards and controllers
use an RS485 network connection to communi-
cate with E2 site controllers. Technicians who
are familiar with CPC’s previous generation
16AI, 8IO, and ARTC boards will find the net-
work setup procedure for the MultiFlex boards
to be very much the same.
3.1. Wiring Types
CPC specifies all RS485 I/O and MODBUS
wiring used by the E2 must be Belden 8641
(24AWG, 300V, CPC P/N 135-8641); Belden
8761 (22 AWG, 300V not stocked by CPC); or a
600V-shielded 22AWG equivalent stocked by
CPC (P/N 135-0600). These are two-connector
shielded twisted pair cable that support a maxi-
mum daisy chain cable distance of 4000 feet
(1219 m) between the E2 and the end device on
the network.
Provided the cable can be routed away from
noise generators and avoid running in parallel
with high-voltage wire, any of the three speci-
fied cables will provide adequate shielding from
external noise. For more instructions on best
practices for minimizing noise, refer to publica-
tion
026-1903, E2 Controller Wiring Practices,
available in the Product Manuals section of the
Emerson Retail Solutions website (
http://
www.emersonretailsolutions.com/library ).
3.2. Daisy Chains
The RS485 Input/Output (I/O) network is
wired in a daisy-chain configuration. In a daisy
chain, boards are wired together in series with no
branches or "star configurations," and the net-
work is terminated at either end of the daisy
chain.
A diagram of this network arrangement is
shown in Figure 3-1 .
3.2.1. Network ID Numbers
Each device on an RS485 segment has a net-
work dip switch that must be used to assign the
board a unique
network ID number .
The network ID number makes a board
unique from other boards on the network of the
same type. This allows the site controller to find
it and communicate with it.
Boards of the same type should be numbered
in sequence, starting with one and continuing
with two, three, etc.
3.2.1.1. Numbering the MultiFlex PAK
The network ID on the MultiFlex PAK is set
using the first five dip switches on dip switch
bank S3. Refer to
Figure 3-2 for dip switch set-
ting instructions.
Figure 3-1 - I/O Network Configurations
TERMINATION
TERMINATION