Siemens ISOLATED MULTI-DROP SG-6048-01 用户手册

Appendices

Siemens Energy & Automation, Inc.

 13

The illustration below is a block diagram showing how the Isolated Multi-Drop converter operates. 
The diagram identifies the internal components that make up the converter.

Figure A.1. Block Diagram

25-pin D 
Connector

RXD

TXD

RTS

DCD

Signal 
Ground

RS-232 
Transceiver

3

2

4

8

7

Galvanically Isolated 
RS-485 Logic

Tx Enable

+

-

SHIELD

RS-485
Port 1

Tx Enable

+

-

SHIELD

RS-485
Port 2

Tx Enable

+

-

SHIELD

RS-485
Port 3

Tx Enable

+

-

RS-485
Port 4

Earth Ground

Baud 
Switch

Tx 

Enable 

Logic

RTS/DCD

AUTO/MAN

RTS

DCD

MAN

AUTO

RS-232 
Connector

Earth Ground

+

-

External 15V DC output

Isolated 
Supply

5V

Power Supply

5V

15V

120 VAC/

Source

125 VDC

DC

DC

SHIELD

Opto-isolators 
for each data 
channel

RS-485 
Transceiver (4)