Advantech RS-485 user manual Line Termination, Figure C-4 ADAM-4000 and ADAM-5000 in a network

RS-485 Network

Combination of an ADAM-4000 and an ADAM-5000 in a RS-485 Network

The following figure shows how to integrate ADAM-4000 and ADAM-5000 systems in a network.

Coverter

RS232/RS485

RS-232

repeater

1

1

2

3

Repeater

2

RS-485

ADAM-5000

SYSTEM

ADAM-4000 I/O

MODULES

Figure C-4 ADAM-4000 and ADAM-5000 in a network

Note: The speed of ADAM-4000 and ADAM-5000 in a RS- 485 network should be the same.

C.2 Line Termination

Each discontinuity in impedance causes reflections and distortion. When a impedance discontinuity occurs in the transmission line the immediate effect is signal reflection. This will lead to signal distortion. Specially at line ends this mismatch causes problems. To eliminate this discontinuity, terminate the line with a resistor.

C-6 ADAM-5000