KEBA SI485/422 (KeConnect I/O serial port module, commonly known in the market, corresponding to the official SM210/A) I. Product Overview
KEBA SI485/422 (KeConnect I/O serial port module, commonly known in the market, corresponding to the official SM210/A) I. Product Overview
The KEBA SI485/422 is a dual-channel isolated RS-485/422 serial communication module under the Kemro K2 platform of the KeConnect I/O system of Austrian KEBA (Kemba). It is an industrial-grade serial port expansion unit specifically designed for injection molding, die-casting, machine tools, robots, and automated production lines. The module is seamlessly connected to the C5/C1 series controllers via the KEBA dedicated K-bus backplane bus, enabling long-distance, highly resistant-to-interference, and multi-node data interaction between third-party serial port devices (such as instruments, sensors, drivers, barcode scanners, RFID, etc.) and the main control system. It is the core component for serial port communication expansion in environments with strong electromagnetic interference.
II. Core Positioning and Naming Explanation
Official model: SM210/A (2-channel RS-485/422), SM220/A (1-channel RS-485/422);
Market nickname: SI485/422 (emphasizing interface type and protocol);
Product positioning: Dedicated differential serial port expansion module, different from SI101 (three-in-one serial port), focusing on long-distance, multi-node, and strong-interference scenarios of RS-485/422.
III. Core Functions
Dual-channel independent differential communication
Equipped with 2 completely independent RS-485/422 interfaces, each channel can be independently configured as RS-485 half-duplex or RS-422 full-duplex, without mutual interference, supporting simultaneous connection of two different serial port devices, enhancing expansion capability.
Long-distance high-speed transmission
Supports a wide range of baud rates from 1200 to 115200 bps; at 9600 bps standard rate, the maximum transmission distance can reach 1200 meters, suitable for cross-workshop, long-distance equipment communication.
Enhanced electrical isolation, strong anti-interference ability
Each channel achieves 2500V AC high-voltage electrical isolation with the system side and between channels, effectively blocking industrial interference such as frequency converter harmonics, motor start-stop impact, and power grid fluctuations, protecting the main control system and peripheral devices, and reducing communication error rates.
Multi-protocol compatibility, wide adaptability
Supports standard Modbus RTU, ASCII protocols, and user-defined serial port protocols, directly connecting to third-party temperature/pressure instruments, servo/step drives, barcode scanners, RFID readers, electronic scales, etc.
Built-in terminal resistor, convenient bus networking
Each channel is equipped with a 120Ω terminal resistor, enabled/disabled manually through the module side dip switch, suitable for RS-485 bus-type multi-node networking (up to 32 slave devices), no need for additional external resistors.
K-bus backplane bus, plug-and-play
Connected via the KEBA dedicated K-bus high-speed backplane bus, automatically recognized, automatically configured, supporting hot swapping, during operation, the module can be directly replaced without downtime and power-off, shortening maintenance time and improving system availability.
Complete diagnosis and status indication
Each channel is equipped with independent **TX (transmit, yellow), RX (receive, yellow), FAULT (fault, red)** LED indicators, combined with the power indicator light (green), can intuitively determine the power supply, data transmission, and communication fault (short circuit, reverse connection, parameter mismatch) status, quickly locate the problem.
Industrial-grade wide temperature and reliable design
Uses reinforced PCB, industrial-grade components, and fully sealed dustproof structure, operating temperature 0℃ to +55℃, suitable for high-temperature, high-humidity, and high-dust workshop environments, supporting 24-hour continuous stable operation.
IV. Technical Parameters (Official Standard Specifications)
Market nickname model: SI485/422
Official corresponding model: SM210/A Series: Kemro K2-200/K2-400 Platform (KeConnect I/O)
Serial ports: 2 independent RS-485/422 (each channel can be set to half-duplex / full-duplex)
Supported protocols: RS-485 (half-duplex), RS-422 (full-duplex), Modbus RTU, ASCII, custom protocol
Baud rate: 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 bps
Data frame format: 7/8 data bits, no / odd / even parity bits, 1/2 stop bits (software configurable)
Electrical isolation: Channel ↔ System, Channel ↔ Channel, isolation voltage 2500V AC
Terminal resistor: Built-in 120Ω per channel, switchable for enabling / disabling
Power supply method: 24V DC (supplied by K-bus backplane bus, no external power supply required)
Power consumption: ≤ 2.5W
Protection functions: Overvoltage, overload, short circuit, reverse polarity, communication abnormality, ESD protection
Address configuration: 16-bit DIP address switch on the side (sets K-bus communication address to avoid conflicts)
Status indication: Green (power), Yellow (TX/RX, independent per channel), Red (FAULT, independent per channel)
Operating temperature: 0℃～+55℃
Storage temperature: -40℃～+70℃
Humidity requirement: 10%～95% (no condensation)
Protection grade: IP20 (front of the module, dust-proof and anti-electric shock)
Size (width × height × depth): 22.5mm × 120mm × 100mm (including K-bus plug)
Weight: Approximately 135g
Terminal connections: 5.08mm spacing open-gold terminals, reliable contact, anti-corrosion
Certifications: CE (EMC/LVD), RoHS, UL 508, EN 61131-2 (industrial control standard)
V. Mechanical and Environmental Characteristics
Compact standardized design
Adopts unified size of KeConnect I/O modules (22.5×120×100mm), fully compatible with SI101, AI/AO/DI/DO series modules, neat cabinet layout, saves installation space; lightweight (135g), suitable for high-density I/O expansion scenarios.
Reinforced dust-proof structure
PCB board reinforced treatment, component sealed protection, front IP20 protection grade, can block dust and foreign matter intrusion, suitable for long-term operation in harsh industrial environments.
Wide temperature stable operation
Working temperature covers 0℃～+55℃, meets the requirements of injection molding, die-casting, machine tools, etc. in high-temperature workshops; storage temperature -40℃～+70℃, convenient for transportation and storage.
VI. Wiring Specifications
RS-422 (4-wire full-duplex) wiring
Module TX+ ↔ Device RX+
Module TX- ↔ Device RX-
Module RX+ ↔ Device TX+
Module RX- ↔ Device TX-
Module GND ↔ Device GND (common ground, reduces interference)
RS-485 (2-wire half-duplex) wiring
Module A+ ↔ Device A-
Module B- ↔ Device B-
Module GND ↔ Device GND
Enable 120Ω terminal resistor at both ends of the bus (start and end nodes) to avoid signal reflection.
Cable selection and grounding
Use shielded twisted pair (0.75–1.5mm²), single-ended grounding of the shield layer (module side), reduces electromagnetic interference;
When the cable length exceeds 500 meters, it is recommended to use dedicated industrial shielded cables to ensure transmission stability. VIII. Typical Application Scenarios
Injection Molding Machine Control System
Connect serial temperature / pressure instruments, RFID readers, barcode scanners, etc., to achieve real-time collection of injection process parameters, upload of product traceability data, and monitoring of equipment status.
Multi-drive Control for Die-Casting Machines
Connect multiple servo drives via RS-485 bus to synchronize control of injection, pressurization, mold opening, ejection, etc., and adapt to non-standard drive equipment integration, improving control synchronization.
Serial Port Expansion for Industrial Machines
Connect spindle encoders, tool sensors, serial digital display instruments to achieve data collection for machine processing, tool life monitoring, and data upload for precision detection, suitable for upgrading of old machines.
Data Interchange in Automated Production Lines
Connect electronic scales, testing instruments, barcode devices, vision sensors to achieve product weight detection, quality data collection, and product information traceability in the production line, suitable for packaging, electronics, and automotive manufacturing industries.
Long-distance Multi-node Networking
In large factories and cross-department scenarios, network via RS-485 bus, connect serial devices (sensors, instruments, actuators) distributed in different areas, achieve centralized monitoring and data management.
IX. Installation and Commissioning Key Points
Installation Steps
When the power is off, align the module with the K2 series backplane slot and push it in smoothly, locking with the snap catch;
Set the unique K-bus address through the 16-bit address switch on the side to avoid conflicts with other modules;
After powering on, the controller automatically recognizes the module, and configures each channel parameters (protocol, baud rate, data frame format, terminal resistor) in the programming software;
Support hot swapping, after replacing the module during operation, the system automatically reidentifies, no restart required.
Commissioning Considerations
Before wiring, confirm the interface type of the equipment (RS-485/422), avoid wiring errors and interface burnout;
When networking via bus, only the first and last nodes enable the terminal resistor, and the intermediate nodes are disabled to prevent signal reflection;
Communication parameters (baud rate, parity bit, data bit, stop bit) must be exactly the same as the slave devices;
If communication is abnormal, prioritize checking wiring, terminal resistor, and parameter configuration, then investigate the module and equipment hardware.
X. Core Differences from SI101
SI485/422 (SM210/A): 2 RS-485/422 dedicated channels, 2500V isolation, long distance (1200 meters), multi-node networking, priority in strong interference scenarios;
SI101: 1 RS-232/422/485 three-in-one, 500V isolation, short distance (≤500 meters), single-device connection, universal scenarios compatible.
XI. Troubleshooting Guide
Green Power LED does not light up, module not recognized
Check if the K-bus backplane bus is securely plugged in and the 24V DC power supply is normal;
Confirm the side address switch settings are correct and there is no address conflict;
Check if the slot is damaged, replace the slot for testing;
Check if the environmental temperature is outside the range of 0℃ to +55℃, power off and cool down before retrying.
Red FAULT LED lights up (single channel / dual channel)
Immediately power off, check if the serial port wiring is short-circuited, reversed, or loose;
Confirm that the communication parameters (baud rate, parity bit, data frame format) are completely matched with the slave devices;
Check if the slave devices are damaged, if the power supply is normal;
Check if the shielding layer grounding is good, and there are no strong electromagnetic interference sources nearby (frequency converter, large power motor).
Yellow TX/RX LED does not flash, no data transmission
Confirm the serial port wiring is correct (RS-422 crossed, RS-485 A/B wiring sequence is correct);
Check if the terminal resistor settings comply with networking requirements (enable at both bus ends);
Check if the slave devices are working normally, if there is data transmission;
Test whether the serial port interface of the module is damaged, and replace the module for verification.