Modbus Bus Terminal Controller BC7300
Power LEDs
K-bus
Bus Coupler
supply
Input for
power contacts
Power contacts
Fieldbus connection
Address selector
Configuration and
programming interface
Address selector

BC7300 | Modbus Bus Terminal Controller

The Bus Terminal Controller BC7300 is a Bus Coupler with integrated PLC functionality and has a fieldbus interface for Modbus. The BC7300 is an intelligent slave and can be used as a non-central intelligence in the Modbus system. One unit consists of the Bus Terminal Controller, any number of terminals between 1 and 64, and a bus end terminal. Because of the low baud rate used by the Modbus protocol, use of the BC7300 may be of value to reduce the bus communication. Time-critical connections can also be programmed directly at the Bus Terminal Controller.

The Bus Terminal Controller is programmed using the TwinCAT programming system according to IEC 61131-3. The configuration/programming interface on the BC7300 is used to load the PLC program.

The inputs and outputs of the connected Bus Terminals are assigned in the PLC’s default setting. Each Bus Terminal can be configured in such a way that it exchanges data directly through the fieldbus with the higher-level automation device. Similarly, pre-processed data can be exchanged between the Bus Terminal Controller and the higher-level controller via the fieldbus. Configuration is performed using the KS2000 configuration software.

Controller for distributed signal processing

The programming system TwinCAT for the BC7300 operates, independently of the manufacturer, in accordance with IEC 61131-3. The PLC programs can be written in five different programming languages (IL, FBD, LD, SFC, ST). In addition, TwinCAT offers extensive debug functionalities (breakpoint, single step, monitoring, …), which facilitate commissioning. It is also possible to perform adjustment and measurement of the cycle time.

PLC data Modbus | BC7300
Programming TwinCAT (via programming interface or fieldbus)
Program memory 32/96 kbytes
Data memory 32/64 kbytes
Remanent data 512 bytes
Runtime system 1 PLC task
PLC cycle time approx. 3 ms for 1,000 instructions (without I/O cycle, K-bus)
Programming languages IEC 61131-3 (IL, LD, FBD, SFC, ST)
Online change
Technical data BC7300
Number of Bus Terminals 64
Max. number of bytes fieldbus 512 byte input and 512 byte output
Digital peripheral signals 256 inputs/outputs
Analog peripheral signals 128 inputs/outputs
Protocol RTU/ASCII (default: RTU)
Configuration possibility by rotary switch or KS2000
Data transfer rates 150, 300, 600, 1200, 2400, 4800, 9600, 19,200, 38,400 baud (default: 9600 baud)
Bus interface D-sub 9-pin, RS485
Power supply 24 V DC (-15 %/+20 %)
Input current 70 mA + (total K-bus current)/4, 500 mA max.
Starting current 2.5 x continuous current
Recommended fuse ≤ 10 A
Current supply K-bus 1750 mA
Power contacts 24 V DC max./10 A max.
Electrical isolation 500 V (power contact/supply voltage/fieldbus)
Weight approx. 170 g
Operating/storage temperature 0…+55 °C/-25…+85 °C
Relative humidity 95 %, no condensation
Vibration/shock resistance conforms to EN 60068-2-6/EN 60068-2-27
EMC immunity/emission conforms to EN 61000-6-2/EN 61000-6-4
Protect. class/installation pos. IP 20/variable
Approvals CE, UL, Ex, GL
Accessories  
KS2000 configuration software for extended parameterisation
TX1200 programming system conforms to IEC 61131-3
Cordsets cordsets and connectors
Related products  
BK7300 Modbus Bus Coupler for up to 64 Bus Terminals
BK7350 Modbus “Compact” Bus Coupler for up to 64 Bus Terminals (255 with K-bus extension)
System  
Modbus For further Modbus products please see the system overview