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Interface rs-485, Connection way of the serial interface – CIRCUTOR DHB Series User Manual

Page 28

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28

PrH1, PrH2,

PrH3, PrH4

4, 5, 6, 7

2000

dLY1, dLY2,
dLY3, dLY4,

4, 5, 6, 7

0

LEd1, LEd2,

LEd3, LEd4

4, 5, 6, 7

oFF

P_An

8

InP1

tYPA

8

0_10U

AnL

8

0

AnH

8

99999

bAud

8

19.2

prot

8

r8n1

Addr

8

1

SEt

9

no

SEC

9

0

HOUR

9

Not defined

unit

9

off

tESt

9

off

6. INTERFACE RS-485

DHB-424 programmable digital meters have serial links in RS-485 stan-
dards for the communication in computer systems and with other de-
vices fulfilling Master function. An asynchronous communication cha-
racter protocol MODBUS has been implemented on the serial link. The
transmission protocol describes ways of information between devices
through the serial link.

6.1. Connection Way of the Serial Interface

The RS-485 standard allows to a direct communication of 32 devices
on a single serial link of 1200 m long (at baud rate 9600 b/s). For the