Emerson E2 operation manual Echelon Network and Hardware Setup, Wiring Type, Loop Resistance

8 Echelon Network and Hardware Setup

8.1Overview

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-enabledE2 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).

8.2Wiring Type

Retail Solutions specifies one type of cable for Echelon Network wiring. This cable type’s properties are listed in Table 8-1.

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

8.3Echelon 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.

Overview Echelon Network and Hardware Setup • 8-1