Emerson E2 - Manual (Page 87)

Overview Echelon Network and Hardware Setup • 8 - 1
8 Echelon Network and Hardware Setup
8.1 Overview
Echelon is an optional, two-conductor network that interconnects E2s and other associated devices, such as CC-100
case controllers, TD3 temperature displays, and ESR8 evaporator stepper regulator boards. All Echelon devices are wired
together using the daisy-chain method of network structuring. If an Echelon network-enabled E2 is required, it must be
specifically ordered from Retail Solutions as an Echelon-enabled E2, and equipped with an Echelon plug-in card. See
Section 4.3.1, Echelon Card Plug-In (P/N 537-4860) with mounting screw (P/N 101-4201).
8.2 Wiring Type
Retail Solutions specifies one type of cable for Echelon Network wiring. This cable type’s properties are listed in
Table 8-1.
8.3 Echelon Network
Structuring (Daisy-Chains)
Echelon devices are networked together into configu-
rations called segments. A segment is a group of up to 64
Echelon devices that are connected together on an unbro-
ken series of wires.
The recommended way of constructing an Echelon
Network is called daisy-chaining. In the daisy-chain net-
work configuration, devices are arranged by subnets,
which consist of one E2 and all Echelon devices associ-
ated with the E2.
First, all devices in a subnet are connected in an unbro-
ken chain without branches or “star configurations” (see
Figure 8-1). Then, if more than one E2 is present on-site,
all chains are connected so that the entire network forms a
large unbroken chain, called a daisy chain
(see Figure 8-2). This allows for all devices in the Eche-
lon Network to be hard wired together for trouble free
communication.
Cable Type Level 4, twisted pair, stranded, shielded
Wire Diam./AWG 0.65mm/22AWG
Loop Resistance 106(ohms/km)
Capacitance 49(nF/km)
Table 8-1 - Echelon Network Cable Specifications
Cable Type Retail Solutions Part Number
1 pair, non-plenum 135-2300
1 pair, plenum 135-2301
Table 8-2 - Recommended Wiring