Babel Buster SPX Modbus TCP/RTU Pass-Through Gateway

Part #: CS BBSPX

Babel Buster SPX will translate Modbus RTU queries directly into Modbus TCP queries, or vice versa. Babel Buster SPX 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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Babel Buster SPX, 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 does not interpret or process any data or register numbers. The SPX 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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