Emerson Copeland PerformanceAlert, Installation And Operation Manual

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Connecting the PerformanceAlert™ Modules To the Gateway Board Networking • 5
4 Networking
Networking the PerformanceAlert™ Gateway System
requires interconnecting the Gateway with all Perfor-
manceAlert™ modules on the MODBUS network, as well
as connecting the Gateway to the E2 via the RS485 I/O net-
work port.
Cable Type
Emerson Climate Technologies Retail Solutions speci-
fies 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 maximum daisy chain cable dis-
tance of 4000 feet (1219 m) between the E2 and the end de-
vice on the network.
4.1. Connecting the Perfor-
manceAlert™ Modules To
the Gateway Board
MODBUS network devices must be installed using a
daisy-chain network structure. A daisy-chain connects the
Gateway and all associated PerformanceAlert™ modules
in a single unbranched network segment, with termination
resistance applied to the network at the two end devices.
Figure 4-1 shows two diagrams of valid daisy-chain net-
work structures, one with the Gateway at the beginning of
the network segment, and one with the Gateway in the mid-
dle of a network segment.
4.1.1. PerformanceAlert™ Module
MODBUS Wiring
The MODBUS connector for the PerformanceAlert™
module is located as shown in Figure 4-2 . Connect the
MODBUS network cable segment(s) so that the BLACK
wire connects to all positive (+) terminals and the WHITE
wire connects to all negative (-) terminals. Connect the
SHIELD wire to the GND terminal of the connector.
The GND terminal of each module must also be con-
nected to a separate solid earth ground, using a 14AWG
wire no more than six (6) inches in length.
The best earth ground sources to use are listed below, in
priority order:
• A large metal panel or plate that is connected to a
good electrical ground. A panel or plate that is at
least 3 feet by 3 feet (0.9 m by 0.9 m) is desirable.
• Earth grounded steel rack.
• Water pipes (metal, assuming there are no plastic
sections).
• Electrical system earth ground.
Figure 4-1 - MODBUS Daisy Chain Structures
Figure 4-2 - PerformanceAlert™ MODBUS Wire Connection
Note: If grounding against a metal plate or
panel that is coated or painted, scrape away
the coating to expose the bare metal before
making the ground attachment.