REX 300, Ethernet Router

REX 300, WAN + Analogmodem, PROFIBUS/MPI, serielle Schnittstelle
REX 300, WAN + Analogmodem, PROFIBUS/MPI, serielle Schnittstelle

REX 300 WAN+analog Modem, PROFIBUS/MPI, serial interface

The REX 300 Ethernet routers are specially designed for use in an industrial environment.

They enable reliable and secure Internet remote maintenance of machines and systems. Thanks to the integrated Firewall, remote access is allowed only for authenticated users.
In combination with the myREX24 V2 portal, the complete scope of performance of industrial routers with the functions of remote maintenance, visualization, WEB2go, alarm and logging of the PLC data is possible.

An additional serial port makes it possible to also incorporate serial devices into your remote maintenance (Serial-over-IP).

  • Secure OpenVPN remote maintenance access via myREX24 V2 portal
  • Integrated firewall
  • Data server for data access to PLCs via RFC1006 (ISO on TCP), MPI, PROFIBUS, Modbus TCP/RTU, Allen Bradley, etc.
  • Directly connect S7-MPI/PROFIBUS devices
  • S7-MPI/PROFIBUS driver included
  • Remote maintenance of PROFIBUS (RS232/RS485) and Ethernet-compatible devices
  • Serial-over-IP
Download PDF datasheet
General information
Order number 700-872-MDM02
Article name REX 300 WAN + analog modem, PROFIBUS/MPI, serial interface
Scope of delivery REX 300, telephone cable, Ethernet cable, Quick Start Guide
Dimensions (DxWxH) 125 x 40 x 128
Weight Approx. 300 g
Analog modem
Analog modem Analog interface, max. 56 kbps (V.92)
Data transmission rate Set speed of 115.2 kbps
Modem port RJ-12 socket
Transmission standards / protocols V.90, V.34+, V.34, V.32bis, V.32, V.22, V.22bis, V.21, V.23
WAN interface
Number 1
Type 10 Base-T/100 Base-T
Connection RJ45 socket
Transmission rate 10/100 Mbps
LAN interface
Number 1
Type 10 Base-T/100 Base-T
Connection RJ45 socket
Transmission rate 10/100 Mbps
USB interface
Protocol USB 2.0 host
Connection USB A socket
Serial Interface
Type RS232/RS485
Protocol transparent access via virtual COM port
Transmission rate 300 Baud ... 115 kBaud
Connection RJ45 socket
MPI/PROFIBUS interface
Transmission rate 9.6 kbps ... 12 Mbps
Connection Socket, SUB-D, 9-pin
Status indicator 6 LEDs, function status
4 LEDs, Ethernet status
Voltage supply 24 V DC, 10–30 V DC
Current draw Max. 500 mA with DC 24 V
Ambient conditions
Ambient temperature 0 °C ... +50 °C
Transport and storage temperature -20 °C … +60 °C
Relative air humidity 95 % r H without condensation
Pollution degree 2
Protection rating IP20
Certifications CE
RoHS Yes


 Name Version Size Tags
REX 300, Firmware (for devices with order numbers ending in 02) 3.7.0 12 MB History
REX Ethernet Router, shDIALUP 3.7 R1.0 34 MB


 Name Version Size Tags
NETLink-S7-NET Driver, for Windows 7/8/10 32/64 Bit 11 MB History

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