Rockwell Automation 1336-GM1 Remote I/O Communications Module - Manual (Page 32)

3–2 Installing the Module
Remote I/O Cables
Remote I/O communications modules are connected to Remote I/O
links with twinaxial cable used for Remote I/O and Data Highway
Plus (DH+) communications. When selecting a cable, remember the
following:
• Only 1770-CD Belden #9463 is tested and approved for RIO and
DH+ installations. Using other cables is at your own risk.
• The total cable length depends on the baud rate that you are
using. Refer to the following table:
• All three of the following conductors must be connected at each
node.
• Do not use a star topology. Only two cables may be connected at
any wiring point. You can use a series topology and daisy-chain
two wires at a point.
Selecting a Termination
Resistor You must terminate both ends of a Remote I/O link to ensure proper
operation. This termination is required only at the ends of the
physical cable. Each Remote I/O link should have exactly two
termination resistors.
If the device that you connect is an end device on the Remote I/O
link, it must be terminated. Refer to the following table to select a
resistor.
Important: You must use an 82 ohm external termination resistor if
the link is operating at 230.4 kbps.
Baud Rate Maximum Length
57.6 K 3,048 m (10,000 ft)
115.2 K 1524 m (5,000 ft)
230.4 K 762 m (2,500 ft)
Color Description
Blue 1
Shield SH
Clear 2
Device Description
Programmable Controller Refer to its manual.
1336-GM1
(Using Jumpers)
Set J2 in position 1-2 for termination and 2-3 for no termination.
Refer to Figure 3.8. The jumper enables a 150 ohm resistor
➀ .
1203-GD1, 1203-GK1, or
1336-GM1
(Using an external termi-
nation resistor)
Connect a resistor between terminals 1 and 2 on the Remote I/O
connector. Refer to Figure 3.4.
Use an 82 ohm termination resistor unless a device requires a
150 ohm termination resistor
➀ .
➀ The following scanners require 150 ohm termination resistors on the RIO link: 1771-SN, 1772-SD,
1772-SD2, 1775-SR, 1775-S4A, 1775-S4B, 6008-SQH1, and 6008-SQH.
The following adapters require a 150 ohm termination resistors on the RIO link: 1771-AS, 1772-ASB
(Series A), 1771-DCM.
The following devices require a 150 ohm termination resistors on the RIO link: 1771-AF.