Networking; Connecting The Ch Breaker Gateway To The Breaker Panels; Terminating The Modbus Network; Setting The Prc100Mod Address - Emerson CH Breaker Gateway Installation And Operation Manual

4

Networking

4.1. Connecting the CH Breaker
Gateway to the Breaker Pan-
els
The Cutler-Hammer breaker panels connect to the
Gateway by MODBUS network connection. MODBUS is
a two-wire, polarity-sensitive network physically similar to
RS485. Using shielded, two-conductor 22AWG wire
(Belden #8761 or equivalent), connect all panels in a single
daisy-chain network configuration leading from the Gate-
way to each of the breaker panels in series.
Figure 4-1 shows how to connect the wires to the
MODBUS connectors.
IMPORTANT! The polarity of the PRC100MOD con-
nectors is the opposite of the Gateway board's connector.
The wire color connected to the positive (+) terminal of the
Gateway board should be wired to the negative (-) terminal
on the breaker panels, and vice-versa.
MODBUS
CONNECTOR
PRC100MOD
Gateway
Board
GATEWAY
MODBUS
CONNECTOR
- (BLACK)
0V (SHIELD)
+ (WHITE)
Figure 4-1 - MODBUS Connection Diagram
4.1.1. Terminating the MODBUS Net-
work
The two devices at the ends of the MODBUS network
must be terminated. If the Gateway board is one of the end
devices, terminate the network using the three termination
jumpers located next to the Gateway MODBUS Connector

Connecting the CH Breaker Gateway to the Breaker Panels

MODBUS
CONNECTORS
PRC100MOD
PRC 100
MODBUS
+ (BLACK)
CONNECTORS
- (WHITE)
NOTE: POLARITY
ON PRC 100
MODBUS
0V (SHIELD)
CONNECTORS
IS THE INVERSE
+ (BLACK)
OF THE GATEWAY
- (WHITE)
WIRE + on Gateway
to - on PRC100s
WIRE - on Gateway
0V (SHIELD)
to + on PRC100s
(Figure 4-2). PRC100MOD boards have no on-board ter-
mination and must be terminated with a 150-ohm resistor
across the + and - terminals (Figure 4-2).
TERMINATION
PRC100MOD
Gateway
Board
TERMINATION
NO
TERMINATION
Figure 4-2 - MODBUS Network Termination
4.1.2.

Setting the PRC100MOD Address

The PRC100MOD controllers on the Cutler-Hammer
breaker panels have a switch used to set the MODBUS ad-
dress. This switch must be used to give each PRC100MOD
a unique address from 1 through 4. Figure 4-3 shows the
switch location and positions for each MODBUS address.
MODBUS
CONNECTOR
PRC100MOD
Gateway
Board
GATEWAY
MODBUS
CONNECTOR
- (BLACK)
0V (SHIELD)
+ (WHITE)
Figure 4-3 - MODBUS Addressing Switch Positions
TERMINATION
PRC100MOD
150Ω
MODBUS
CONNECTORS
PRC100MOD
PRC 100
MODBUS
+ (BLACK)
CONNECTORS
- (WHITE)
NOTE: POLARITY
ON PRC 100
MODBUS
0V (SHIELD)
CONNECTORS
IS THE INVERSE
+ (BLACK)
OF THE GATEWAY
- (WHITE)
WIRE + on Gateway
to - on PRC100s
WIRE - on Gateway
0V (SHIELD)
to + on PRC100s
Networking • 3