Wiring Types
The I/O Network • 7
3
The I/O Network
Although the MultiFlex CUB can operate as
a stand-alone controller, it relies on an E2, Ein-
stein, or REFLECS unit for advanced features
such as remote dial-in/dial-out, logging, and
alarm control. All MultiFlex boards and control-
lers use an RS485 Network connection to com-
municate with an E2, Einstein, and REFLECS
site controllers. Technicians who are familiar
with CPC’s previous generation 16AI, 8IO, and
ARTC boards will find the network setup proce-
dure for the MultiFlex CUB boards to be very
much the same.
3.1. Wiring Types
CPC specs Belden #8761 shielded twisted
pair cables for use as I/O Network wiring (or
Belden #82761 and Belden #88761 for plenum
installations).
If the recommended cable is not available in
your area, be sure the wiring meets or exceeds
the following specs:
3.1.1. Daisy Chains
The RS485 Input/Output (I/O) Network con-
nects all input and output communication boards
together in a single open communications loop.
This loop, or “daisy chain,” connects the E2,
Einstein, or REFLECS to multiple input and out-
put communication boards, and terminates at the
last input or output board on the network. A dia-
gram of this network arrangement is shown in
Figure 3-1
.
3.1.2. 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 easily.
Boards of the same type should be numbered
in sequence, starting with one and continuing
with two, three, and so forth.
Shielded?
Yes
Conductor Type
Twisted Pair
Gauge
18 - 24 AWG
Capacitance between
signal wires
31 pF/ft or less
Capacitance between
signal and shield
59 pF/ft or less
Nominal Impedance
120
50
Table 3-1 - RS485 I/O Network Wiring Specifications
Figure 3-1 - I/O Network Configurations
