A functioning TB20 configuration will always require a bus coupler and at least one peripheral module, but can accommodate up to 64 modules of any kind connected in series with the bus coupler. The bus coupler supports hot-plug for replacing modules during operation.
It detects peripheral modules that are plugged in and assigns the I/O data and parameters of each module to the corresponding Modbus registers.
The Modbus/TCP bus coupler features an integrated two-port switch that allows for star and line topology configurations.
A large I/O image table size of 2 kbytes makes it possible to implement comprehensive and complex systems.
The control and status registers can be used to configure and monitor the coupler`s behavior with Modbus/TCP.
TB20 ToolBox can be used to easily configure the system and the various module parameters and transfer the corresponding settings to the coupler.

Note:

The 24 V power supply connector, the final bus cover, and the base module are included as standard.
TB20 ToolBox makes it easy to methodically design TB20 systems. Integrated terminal mapping, system width calculations, and current-carrying capacity monitoring all make it possible to quickly design systems without making any mistakes. 

Characteristics

• Watchdog for monitoring the connection
• Simultaneous access to up to 10 stations (TCP connections)
• Integrated two-port switch
• Up to 64 peripheral modules
• Modules can be replaced during operation (hot-plug)
• Two RJ45 connectors
• 2048 bytes of input data; 2048 bytes of output data
• 126 bytes of parameter data per module
• The coupler`s behavior can be configured using control registers
• The coupler`s state can be read using status registers
• Supports module diagnostics
• 24 VDC power supply
• Integrated power supply unit for powering peripheral modules (2.5 A)
• Supplies the system’s I/O voltage (24 VDC)
• 7 LEDs, two of them bi-color
• USB device port for online diagnostics, configuring parameters, setup, and firmware updates with "TB20 ToolBox"
• TB20 ToolBox simulation for setting up the I/O system without a higher-level controller in order to test the system`s 
  operation (I/O check)
• Concealed "factory reset" switch for restoring the module to its factory settings