2ć23, Termination – Rockwell Automation 1770-HT8 SMART TRANSMITTER User Manual
Page 48

Installing the Smart Transmitter Interface
Products
Chapter 2
2-23
Figure 2.20
RIO Connector
90014
POWER
RIO
Twinaxial Cable (1770-CD)
Blue
Clear
Shield
1 SH 2
RIO
The pinout is:
Signal
Label
Cable
A1
1
Blue wire
A2
SH
Shield
A3
2
Clear wire
Use Twinaxial Cable (1770-CD) for the RIO connections. Maximum
length for the cable depends on the baud rate:
For this baud rate:
Maximum cable length is:
57600
10,000 feet (3,048 m)
115200
5,000 feet (1,524 m)
230400
2,500 feet (762 m)
Termination
Terminate the farthest physical nodes on the RIO link with a 150 or 82
Ohm termination resistor. If the Communications Controller is the last
device on the RIO link, connect a 1/2 watt resistor across pins 1 and 2 of
the plug. The value of the resistor depends on the Remote I/O baud rate:
For this baud rate:
Use this terminating resistor:
AllenĆBradley Part Number
57600
150W
#740018Ć29
115200
150W
#740018Ć29
230400
82W
#740018Ć23