KEBA SM250/A (KeConnect I/O High-Speed Serial Port / Ethernet Composite Module) I. Product Overview
KEBA SM250/A (KeConnect I/O High-Speed Serial Port / Ethernet Composite Module) I. Product Overview
The KEBA SM250/A is a multi-functional communication module under the Kemro K2 platform of the KeConnect I/O system of Austrian KEBA (Kemba). It integrates a high-speed serial port (RS-232/485/422) + Ethernet dual interface, specifically designed for injection molding, die-casting, machine tools, robots, and intelligent factory scenarios. It realizes three core functions: networking of serial port devices, expansion of Ethernet communication, and multi-protocol data interaction. The module is seamlessly connected to the C5/C1 series controllers through the dedicated K-bus backplane bus of KEBA and is the core expansion unit for the integration of serial ports and Ethernet communication in strong interference environments.
II. Core Positioning and Naming Explanation
Official Model: SM250/A (Composite Communication Module);
Series: Kemro K2-200/K2-400 Platform (KeConnect I/O);
Product Positioning: Integrated Serial Port + Ethernet Expansion Module, different from SM210/A (pure serial port), SM220/A (single serial port), focusing on Ethernet transmission of serial port devices, dual protocol parallel communication, and remote serial port management scenarios.
III. Core Functions
Dual Interface Composite Communication (Serial Port + Ethernet)
Equipped with 1 multi-function serial port (RS-232/485/422 combined) + 1 10/100Mbps Ethernet port. The dual interfaces work independently and can simultaneously connect serial port devices (instruments, sensors, drivers) and Ethernet devices (upper computer, PLC, cloud platform), achieving Ethernet forwarding of serial port data and dual network parallel communication.
Full-function serial port compatibility, anti-interference design
Serial port supports RS-232 (short distance), RS-485 (long distance / multi-node), RS-422 (full-duplex);
Baud rate 1200–115200 bps, 9600 bps when RS-485 transmission distance 1200 meters;
2500V AC electrical isolation, blocking inverter, motor interference;
Built-in 120Ω terminal resistor (dial switch control), compatible with bus networking.
High-speed Ethernet communication, multi-protocol support
Ethernet port: RJ45, 10/100Mbps adaptive, supports TCP/IP, Modbus TCP, HTTP;
Supports serial port server function (RS-232/485/422 ↔ Ethernet transmission);
Supports remote configuration and diagnosis, remotely manage serial port parameters via Ethernet;
Supports multiple connections concurrency, up to 8 serial port Ethernet connections managed simultaneously.
K-bus backplane bus, plug-and-play
Uses KEBA's dedicated K-bus high-speed backplane bus, automatically identifies, automatically configures, supports hot swapping, can directly replace modules during operation without stopping or power-off, shortening maintenance time.
Complete diagnosis and status indication
Power: Green LED (normal always on);
Serial port: Yellow TX/RX (data transmission flashing), Red FAULT (fault always on);
Ethernet: Green LINK (connection always on), Yellow ACT (data flashing);
Intuitively determine power supply, serial port communication, Ethernet connection status, quickly locate problems.
Industrial-grade reliable design
Strengthened PCB, industrial-grade components, fully sealed dustproof structure;
Operating temperature 0℃～+55℃, suitable for high-temperature, high-humidity, high-dust workshops;
IP20 protection level, dustproof and electric shock protection;
Overvoltage, overload, short circuit, reverse polarity, ESD protection, adapted to harsh industrial environments.
Isolation voltage: 2500V AC (Serial port ↔ System, Serial port ↔ Ethernet);
Terminal resistance: Built-in 120Ω, controlled by dip switch;
Transmission distance: RS-485/422 up to 1200 meters (9600 bps), RS-232 up to 15 meters.
Ethernet parameters:
Rate: 10/100Mbps adaptive;
Protocol: TCP/IP, Modbus TCP, HTTP, DHCP, DNS;
Connection: RJ45, supports automatic crossover (Auto-MDI-X);
Function: Serial port server, remote configuration, data transmission, multi-connection concurrency (up to 8 channels).
Power supply: 24V DC (K-bus backplane power supply, no external power required);
Power consumption: ≤3.0W;
Address configuration: 16-bit DIP address switch on the side (K-bus unique address);
Status indication: Green (power, Ethernet LINK), Yellow (Serial port TX/RX, Ethernet ACT), Red (Serial port FAULT);
Operating temperature: 0℃～+55℃;
Storage temperature: -40℃～+70℃;
Humidity: 10%～95% (no condensation);
Protection grade: IP20;
Size (width × height × depth): 22.5mm × 120mm × 100mm (including K-bus plug);
Weight: Approximately 140g;
Terminal: 5.08mm spacing open-gold terminals;
Certifications: CE (EMC/LVD), RoHS, UL 508, EN 61131-2.
VII. Mechanical and Environmental Characteristics
Compact standardized design
Adopt KeConnect I/O unified size (22.5×120×100mm), fully compatible with SM210/A, SI101, etc. modules, neat cabinet layout, saves space; lightweight (140g), suitable for high-density I/O expansion.
Reinforced dust-proof structure
PCB reinforcement, component sealed protection, front IP20 protection, prevents dust and foreign matter from entering, suitable for long-term operation in harsh industrial environments.
Wide temperature stable operation
Working temperature 0℃～+55℃, meets the requirements of injection molding, die-casting, machine tools, etc. high-temperature workshops; storage temperature -40℃～+70℃, convenient for transportation and storage.
VIII. Wiring Specifications
RS-232 (short distance, point-to-point)
Module TX ↔ Device RX;
Module RX ↔ Device TX;
Module GND ↔ Device GND;
Transmission distance ≤ 15 meters, no terminal resistance required.
RS-485 (long distance, multi-node, 2-wire half-duplex)
Module A+ ↔ Device A+;
Module B- ↔ Device B-;
Module GND ↔ Device GND;
Enable 120Ω terminal resistor at the first and last nodes of the bus, and disable at the intermediate nodes.
RS-422 (full-duplex, 4-wire)
Module TX+ ↔ Device RX+;
Module TX- ↔ Device RX-;
Module RX+ ↔ Device TX+;
Module RX- ↔ Device TX-;
Module GND ↔ Device GND.
Ethernet wiring
Standard network cable (CAT5e and above) connects module RJ45 with switch / host;
Supports automatic crossover, straight-through / crossover network cables are both acceptable;
Recommended shielded network cable, single-ended grounding of the shielding layer, reduces interference.
IX. Typical Application Scenarios
Intelligent networking of injection molding machines Serial port connection for temperature / pressure meters, RFID, barcode scanners, Ethernet connection to the host computer / cloud platform, enabling remote monitoring of injection molding parameters, uploading product traceability data, and networked management of equipment status.
Integration of multiple equipment in the press machine
RS-485 connection for multiple servo drives, Ethernet connection for PLC, synchronous control of injection / ejection actions, and uploading operation data to the MES system, suitable for networking of non-standard drive equipment.
Networked serial port devices for machine tools
Connecting spindle encoders, tool sensors, serial digital indicators, etc., remotely collecting processing data, monitoring tool lifespan, uploading precision test results, suitable for digital transformation of old machine tools.
Remote management of serial port devices on the production line
Connecting electronic scales, testing instruments, barcode devices, Ethernet connection to the factory local area network, enabling remote configuration of serial port devices, centralized data collection, and remote fault diagnosis, improving maintenance efficiency.
Long-distance serial port device networking
In large factories / across workshop scenarios, RS-485 connects distributed serial port devices, Ethernet converges data to the central control system, achieving centralized monitoring and management, reducing wiring costs.
VIII. Installation and Commissioning Key Points Installation steps
During power-off, the module is smoothly pushed into the K2 backplane slot and locked by the latch;
The 16-bit address switch on the side is set with a unique K-bus address to avoid conflicts;
After power-on, the controller automatically recognizes the module, and the programming software configures the serial port (protocol, baud rate, data frame, terminal resistor) and Ethernet (IP, subnet mask, gateway) parameters;
Supports hot swapping, and after replacing the module during operation, the system automatically reidentifies it.
Debugging precautions
Before connecting the serial port, confirm the interface type (RS-232/485/422), to avoid incorrect connection and burnout;
For RS-485 networking, only the first and last nodes enable the terminal resistor, and the intermediate nodes are turned off;
The serial port communication parameters (baud rate, parity bit, data bit, stop bit) are exactly the same as the slave station;
For Ethernet configuration, use a fixed IP (recommended) or DHCP to ensure the same network segment as the upper computer/PLC;
When there is a communication anomaly, first check the wiring, terminal resistor, and parameter configuration, and then investigate the hardware.
IX. Comparison with similar modules
SM250/A: Serial port + Ethernet composite interface, 2500V isolation, supports serial port server, suitable for networking of serial devices, dual protocol communication, and remote management;
SM210/A (SI485/422): Dual RS-485/422, pure serial port, suitable for multiple serial devices, long-distance networking, strong interference;
SI101: Single RS-232/485/422, pure serial port, suitable for single serial device, short distance, general scenarios.
X. Fault Troubleshooting Guide
Power LED does not light up, module not recognized
Check that the K-bus bus is tightened and the 24V DC power supply is normal;
Confirm that the address switch is set correctly and there is no address conflict;
Check for slot damage and replace the slot for testing;
Check if the environmental temperature exceeds 0℃ to +55℃, and retry after cooling off with power off.
Serial port FAULT LED lights up
Check the serial port wiring for short circuit, reverse connection, or looseness;
Confirm that the serial port parameters are completely matched with the slave station equipment;
Check for damage to the slave station equipment, abnormal power supply;
Check that the shielding layer is well grounded and there are no strong interference sources nearby.
Ethernet LINK LED does not light up
Check that the network cable is tightened and the switch port is normal;
Replace the network cable for testing (recommended CAT5e shielded cable);
Confirm that the module's Ethernet IP is in the same network segment as the upper computer/PLC;
Check for damage to the module's Ethernet interface, replace the module to verify.
Serial port data transmission is normal, Ethernet has no data
Check the Ethernet parameters configuration (IP, subnet mask, gateway);
Confirm that the firewall of the upper computer/PLC does not intercept the communication port;
Check the quality of the network cable, replace with shielded network cable;
Check if the serial port server function of the module is enabled.