Description
Designed to bridge the gap between high-speed EtherCAT networks and standard K-bus assemblies, the BK1120 serves as an efficient communication interface for modular automation systems. This bus coupler maps the technical signals from standard Beckhoff Bus Terminals directly into the EtherCAT protocol, enabling seamless integration into distributed control architectures without sacrificing legacy terminal compatibility.
The BK1120 establishes a high-performance link between physical I/O points and the controller. It automatically handles the conversion of process data and local bus diagnostic information, presenting it clearly to the EtherCAT master. With dual RJ45 interfaces, this module supports flexible line and daisy-chain topologies, simplifying field wiring and reducing installation costs in complex control environments.
Features
- Direct integration of standard K-bus terminals into high-speed EtherCAT networks.
- Supports up to 64 standard Bus Terminals directly, and up to 255 Bus Terminals using K-bus extensions.
- Equipped with two RJ45 ports for line topology networking up to 100 meters apart.
- High-density data handling with up to 1024 bytes of input and 1024 bytes of output process data.
- Integrated diagnostic LEDs for quick monitoring of power status, K-bus run, and network communication.
Applications
- Industrial machinery and high-speed packaging lines.
- Distributed I/O architectures in processing and manufacturing systems.
- Retrofitting existing legacy K-bus terminal configurations to modern EtherCAT masters.
- Building automation and HVAC control infrastructure requiring high-density point aggregation.
Technical Specifications
| Manufacturer |
BECKHOFF |
| Part Number / Model |
BK1120 |
| Product Type |
EtherCAT Bus Coupler for standard Bus Terminals |
| Number of Bus Terminals |
64 (up to 255 with K-bus extension) |
| Max. Process Data Space |
1024 bytes input / 1024 bytes output |
| Bus Interface |
2 x RJ45 |
| Distance Between Stations |
Max. 100 m (100BASE-TX) |
| Power Supply |
24 V DC (-15 % / +20 %) |
| Input Current |
70 mA + (total K-bus current)/4 (500 mA max.) |
| Starting Current |
Approx. 2.5 x continuous current |
| Current Supply K-Bus |
1750 mA |
| Power Contacts |
Max. 24 V DC / Max. 10 A |
| Recommended Fuse |
<= 10 A |
| Electrical Isolation |
500 V (power contact / functional ground / K-bus) |
| Operating Temperature |
-25 to +60 degC |
| Storage Temperature |
-40 to +85 degC |
| Relative Humidity |
95%, no condensation |
| Weight |
Approx. 0.15 kg |
Connections and Interfaces
| Interface Type |
Function |
| RJ45 Port 1 (IN) |
EtherCAT signal input connection from previous station or master |
| RJ45 Port 2 (OUT) |
EtherCAT signal output connection to next station in daisy-chain |
| Spring Force Terminals |
24 V DC power supply input and power contact distribution feed |
Installation Guidelines
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Mounting: Install on a standard 35 mm DIN rail (EN 60715). Ensure the mounting slide latches firmly onto the rail.
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Cabling: Use category 5e (or higher) shielded Ethernet cables to guarantee proper signal integrity and noise immunity.
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Grounding: Ensure the DIN rail is reliably connected to a low-impedance functional earth grounding point.
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Power Supply Routing: Keep power lines as short as possible and separate them from high-frequency signal cables to prevent interference.