Babel Buster SPX-GW Modbus TCP/RTU Pass-Through Gateway

Part #: CS BBSPX

Babel Buster SPX-GW will translate Modbus RTU queries directly into Modbus TCP queries, or vice versa. Babel Buster SPX-GW is used to connect Modbus RTU devices to a Modbus TCP network, or Modbus TCP devices to a Modbus RTU network without register remapping.
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  • Overview

Babel Buster SPX-GW, transparent pass-through gateway, is used when you simply want to convert Modbus RTU to Modbus TCP or vice versa. Access multiple RTU devices from a single TCP port, or access multiple TCP devices from a single RTU port.

RTU Devices on a TCP Network: Mapping multiple RTU devices to a single TCP IP address means the TCP port looks like a Modbus slave while the RTU port looks like a Modbus master to multiple slaves on the EIA485 link. The TCP master must provide valid unit numbers to select the different RTU devices.

TCP Devices on an RTU Network: Mapping multiple TCP devices to multiple Modbus RTU addresses means the RTU side acts as a Modbus slave while the TCP side acts as Modbus master connecting to multiple Modbus TCP slaves.

If register renumbering is needed, then the standard SPX must be used. The SPX-GW does not interpret or process any data or register numbers. The SPX-GW only processes packet source and destination. 


  • Modbus RTU Master or Slave
  • Modbus TCP Client and Server
  • Modbus RTU RS-485 (only)
  • Modbus TCP over Ethernet 10/100BaseT
  • 240 Modbus RTU Devices Supported
  • 20 Modbus TCP Devices Supported
  • Web UI for Configuration and Diagnostics
  • DHCP or Static IP address
  • Powered by 9 to 30VDC @ 0.37A to 0.11A
  • FCC Class A, CE Mark
  • Operating temperature -40°C to +85°C
  • Humidity 5% to 90%
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