Hardware Manual

Saia-Burgess Controls AG

Hardware Manual PCD 1 / PCD 2 Series│Document 26 / 737│Edition EN 15│2008-07-22

Communication interfaces

4

Serial interface on Port #6

4.4.5 RS 485 communiaction interface PORT # 6, only on PCD2.M480

On the PCD2.M480, on Port #6, is a built-in RS 485 interface.

29

27

26

25

24

23

22

21

20

D

/D

WD

WD

PCD 2 .M 480

RX - TX

/RX - /TX 28

RS 485

Bus-cable

Screw terminal block

O

C

Choice of the termination resistors

PCD 2 .M 480

Port #6

PCD 1 .M1xx

PCD2.Mxx0

PCD 1 .M1xx

PCD2.Mxx0

PCD 1 .M1xx

PCD2.Mxx0

/RX-/TX

n n

n

/n

/n /n

RX-TX

+ 5 V

29

28

+ 5 V

Pullup

330 Ohm

Termination

Resistor

150 Ohm

Segment length max. 1200 m

max. 32 stations

BusRS 485

First station Middle stations End station

Pulldown

330 Ohm

At the first and last stations, the jumper must be set to the “C“ (closed) position.

At all other stations, the jumper must be set to “O” (open) position (factory setting).