BK9100 Beckhoff Bus Coupler Modbus TCP TwinCAT ADS 24VDC

BK9100 Beckhoff Ethernet TCP/IP Bus Coupler

The BK9100 from Beckhoff links Ethernet to modular terminal blocks. One node holds one coupler, 1 to 64 terminals, and one end terminal. With K-bus extension, it handles up to 255 Bus Terminals. The coupler reads connected terminals and maps inputs and outputs into the process image automatically. It supports 10 Mbit/s and 100 Mbit/s Ethernet through standard RJ45 ports. The IP address is set by DIP switch or DHCP. Unlike the BK9000, the BK9100 adds a second RJ45 port. Both ports work as a 2-channel switch. This allows line topology instead of star topology. Wiring effort and cable cost drop in many machines. The max distance between couplers is 100 m. Up to 20 BK9100 units cascade for a 2 km line. The coupler supports ADS TwinCAT and Open Modbus (Modbus TCP). It is a solid choice for distributed I/O on legacy and current Beckhoff systems.

Core Function and Topology

• Connects Ethernet to modular electronic terminal blocks.
• One unit: coupler, 1 to 64 terminals, one end terminal.
• K-bus extension supports up to 255 Bus Terminals.
• Auto-assigns inputs and outputs to process image words.
• Two RJ45 ports act as a 2-channel switch.
• Line topology replaces classic star topology.
• Cascades up to 20 couplers, max 2 km line length.
• Max 100 m between hub/switch and coupler.
• Max 100 m between coupler and coupler.

Fieldbus and Protocol Support

• Protocols: TwinCAT ADS, Modbus TCP, Beckhoff real-time Ethernet.
• Data transfer: 10/100 Mbit/s with automatic rate detection.
• Bus interface: 2 x RJ45, 2-channel switch.
• Medium: 4 x 2 twisted pair copper cable.
• Cable category: Cat 3 for 10 Mbit/s, Cat 5 for 100 Mbit/s.
• Max fieldbus bytes: 512 byte input and 512 byte output.
• Digital signals: 512 inputs/outputs.
• Analog signals: 128 inputs/outputs.
• Configuration: via KS2000.

Electrical Data

• Power supply: 24VDC, -15%/+20%.
• Input current: 70mA plus total K-bus current divided by 4.
• Max input current: 500mA.
• Starting current: 2.5 x continuous current.
• Recommended fuse: 10A or less.
• K-bus current supply: 1750mA.
• Power contacts: max 24VDC, max 10A.
• Electrical isolation: 500V between power contact, supply voltage, and fieldbus.

Environment and Protection

• Operating temperature: -25 to +60°C.
• Storage temperature: -40 to +85°C.
• Relative humidity: 95%, no condensation.
• Vibration and shock: EN 60068-2-6 and EN 60068-2-27.
• EMC immunity and emission: EN 61000-6-2 and EN 61000-6-4.
• Protection rating: IP20.
• Installation position: variable.
• Weight: approx 170 g.

Housing and Mounting

• Design: Compact terminal housing with signal LEDs.
• Material: Polycarbonate.
• Dimensions: 51 mm x 100 mm x 69 mm.
• Mounting: 35 mm DIN rail per EN 60715 with lock.
• Side-by-side mounting: Double slot and key connection.
• Wiring: Spring actuation by screwdriver.
• Solid conductor: 0.08 to 2.5 mm².
• Stranded conductor: 0.08 to 2.5 mm².
• Ferrule: 0.14 to 1.5 mm².
• Stripping length: 8 to 9 mm.
• Current load power contacts: Imax 10A.

Approvals and Ex Marking

• Approvals: CE, UL, ATEX, IECEx, DNV GL.
• ATEX: II 3 G Ex ec IIC T4 Gc.
• IECEx: Ex ec IIC T4 Gc.
• Confirm final compliance with local site rules.

Installation Guide

• Mount on 35 mm DIN rail per EN 60715.
• Use double slot and key connection for side-by-side units.
• Keep 100 m max between hub/switch and coupler.
• Keep 100 m max between coupler and coupler.
• Use Cat 5 cable for 100 Mbit/s links.
• Set IP address by DIP switch or DHCP.
• Wire 24VDC with correct polarity.
• Use a fuse rated 10A or less.
• Strip wires 8 to 9 mm before insertion.
• Check signal LEDs after power-up.

Commissioning and Maintenance

• Use KS2000 for configuration.
• Use TwinCAT I/O for ADS communication.
• Access ADS through an OPC server if needed.
• Check RJ45 ports for link and activity LEDs.
• Inspect DIN rail lock during service.
• Verify K-bus current budget before adding terminals.
• Back up configuration before replacement.
• Clean with a dry cloth only.

Compatibility Notes

• Works with Beckhoff Bus Terminals.
• Supports Modbus TCP masters and slaves.
• Supports TwinCAT ADS system communication.
• OPC clients can reach ADS through an OPC server.
• Fits legacy BK9000 style installations with added second port.
• Check project I/O mapping before swapping couplers.

Typical Equipment and Applications

• Distributed I/O stations on Ethernet.
• Line topology machine networks.
• Legacy Beckhoff BK9000 upgrades.
• Modbus TCP control systems.
• TwinCAT ADS automation cells.
• Packaging, handling, and assembly lines.
• Obsolete control system support.

Oiltech Controls Review and Insight

• The BK9100 saves cable cost by using line topology.
• Two RJ45 ports simplify daisy-chain wiring.
• Engineers like the DIP switch IP setup for quick service.
• Modbus TCP support helps mix Beckhoff I/O with third-party PLCs.
• Check K-bus current before adding many terminals.
• Confirm firmware and TwinCAT version before ordering.

Why Buy From Oiltech Controls?

• 15+ years in industrial automation spare parts.
• Global shipment support for hard-to-find items.
• Tested industrial surplus and refurbished options.
• 12-month warranty on eligible products.
• Technical verification before every shipment.
• Support for obsolete control systems.

Packing List and Shipping

• 1 x BK9100 Ethernet TCP/IP Bus Coupler.
• 1 x Quick reference if available.
• 12-month warranty on eligible products.
• Ships in 24 to 28 hours after order confirmation.
• Shipping by FedEx, UPS, and DHL.
• Tracking sent after dispatch.

FAQ

Q: How many Bus Terminals can the BK9100 handle?

A: Up to 64 terminals on one node. With K-bus extension, up to 255 terminals.

Q: What is the real difference between BK9000 and BK9100?

A: The BK9100 adds a second RJ45 port. Both ports work as a 2-channel switch for line topology.

Q: Why does my K-bus current alarm trip after adding terminals?

A: The coupler supplies 1750mA for K-bus. Add up terminal current draw. Use a power terminal if the budget is tight.

Q: Can I use the BK9100 with a non-Beckhoff PLC?

A: Yes, if the PLC supports Modbus TCP. Check register mapping and byte order before commissioning.

Q: How do I choose the right coupler for an obsolete Beckhoff system?

A: Match protocol, port count, terminal type, and power budget. Send us your old model number and we will verify fit.

Contact info@oiltechcontrols.com or WhatsApp +86 158 8020 0923 for stock and fit checks.

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