Rockwell Automation 1747-DCM,D17476.8 Direct Communication Module - Manual (Page 41)

Chapter 5
Installation and Wiring
5–3
A 1/2 watt terminating resistor must be attached across line 1 and line 2 of
the connectors at each end (scanner and last physical device) of the network.
The size of the resistor depends upon the baud rate and extended node
capability, as shown below:
Baud Rate Terminating Resistor Size
Maximum Cable Distance
(Belden 9463)
Using Extended
Node Capability
All Baud Rates 82 W 1/2 Watt
10,000 feet at 57.6K baud
5,000 feet at 115.2K baud
2,500 feet at 230.4K baud
Not Using
57.6K baud 150 W 1/2 Watt 3048 meters (10,000 feet)
Not Using
Extended Node
apab l t
115.2K baud 150 W 1/2 Watt 1524 meters (5,000 feet) xten e o e
Capability
230.4K baud 82 W 1/2 Watt 762 meters (2,500 feet)
Terminating
Resistor
Terminating
Resistor
RIO Scanner
1747-DCM
Direct Communication Module
1747-DCM
Direct Communication Module
Line 1 – Blue
Shield – Shield
Line 2 – Clear
Line 1 – Blue
Shield – Shield
Line 2 – Clear
Line 1 – Blue
Shield – Shield
Line 2 – Clear
DCM
RIO Link
Connector
COMM
FAULT
CONFIGURATION
RACK SIZE
1/4 1/2 3/4 1
RACK ADDR
FIRST I/O GROUP
0 2 4 6
DATA RATE (K B/S)
57.6 115.2 230.4
LINE 1 _______
SHIELD ______
LINE 2 _______
1747–DCM
SW2
SW1
O N
1
2
3
4
567
8
O N
1
2
3
4
567
8
I/O
GROUP
(LSB)
RACK
ADDRESS
(MSB)
RACK
SIZE
DATA
RATE
X
X
LAST RACK
CLR ON FLT
Network Wiring