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Rockwell Automation 1761 MicroLogix 1000 Programmable Controllers User Manual

Page 64

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Preface

MicroLogix 1000 Programmable Controllers User Manual

3–6

DH-485 Communication Cable

The suggested DH-485 communication cable is either Belden #3106A or #9842.
The cable is jacketed and shielded with one or two twisted wire pairs and a drain
wire.

One pair provides a balanced signal line, and one additional wire is used for a
common reference line between all nodes on the network. The shield reduces the
effect of electrostatic noise from the industrial environment on network
communication.

The communication cable consists of a number of cable segments daisy-chained
together. The total length of the cable segments cannot exceed 1219 m (4000 ft).

When cutting cable segments, make them long enough to route them from one AIC+
to the next with sufficient slack to prevent strain on the connector. Allow enough
extra cable to prevent chafing and kinking in the cable.

Use these instructions for wiring the Belden #3106A or #9842 cable. (If you are
using standard Allen-Bradley cables, see the Cable Selection Guide on page 3–12.)