SIEMENS
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Siemens IK PI · 2015
Industrial Remote Communication
Remote Networks
Modems for the conventional telephone network
7
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Overview
SINAUT MD3 modem
Modems are used for wired transmission of signals and data
between individual stations and the control center of a tele-
control system. Siemens offers appropriate modems for both
dedicated lines and dial-up networks.
Like the TIM modules, these are accommodated in an S7-300
enclosure:
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MD2;
dedicated-line modem for multi-point connection,
can be tapped,
can also be used as a repeater,
max. 19 200 bps
•
MD3;
modem for the analog telephone network,
max. 33 600 bps;
can also be used as a dedicated-line modem for a point-to-
point connection,
max. 33 600 bps in voice band
These modems can be connected to the serial modem interface
of a TIM module.
The modems are supplied together with the WAN connecting
cable required in each case. Connecting cables for connecting
the modems to a TIM must be ordered separately.
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Benefits
•
Diverse application options for use in dedicated-line networks
or for conventional telephone networks (analog, ISDN, GSM)
•
Matched to the telecontrol system by means of the design of
the SIMATIC S7-300
•
Electrical isolation between power supply and WAN interface
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Application
The modems can be used in other applications as dedicated-
line modems or dial-up modems independently of the
SINAUT ST7 system.
Due to the design and the electrical properties, the modems are
suited above all for applications in the industrial sector.
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Design
All three modem types are identically designed and offer all the
advantages of the SIMATIC S7-300 design:
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Compact construction;
double standard width of SIMATIC S7-300 SM modules
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RJ12 socket for connecting the modem to the WAN
(leased line or dialup network)
•
9-pin Sub-D connector with an RS232 interface for connection
to the serial interface of a communication module, e.g. TIM
•
9-pin Sub-D socket with an RS 485 interface for connection to
the serial interface of a communication module, e.g. TIM
•
4-pin plug-in terminal strip for connection of the 24 V DC
external supply voltage
•
Front-panel LEDs indicating TXD, RXD, DTR, RTS/ONL,
CTS/RI and DCD
•
Simple installation;
on a mounting rail of the S7-300, or on a 35 mm standard rail
•
The SINAUT ST7 modems can be operated without a fan
© Siemens AG 2014