Interface And Bus Topology; Interface Technology, Rs 485-Bus Systems; Principle; General Information - Honeywell ACS-8 Installation Instructions Manual

Installation Instructions / ACS-8
7.

Interface and bus topology

7.1 Interface technology, RS 485 bus systems
There are two types of data transmission. These are known as point-to-point and multipoint.
In a point-to-point connection two controllers are communicating with each other directly. A point-to-point
connection might use an RS 232 or a current loop interface.
In a multipoint connection, several controllers communicate with one another. The RS 485 interface would
be used for a multipoint connection.
A bus topology is used for the RS 485 interface.

7.1.1 Principle:

7.1.2 General information

The RS 485 interface is a bidirectional interface with bus capability. Up to 32 users can be connected, each
of which can transmit as well as receive. The line ends must have terminating resistors (fitted as standard)
that can be configured on the interface by means of jumpers.
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