COMSOFT FNL-RS485 Network Gateway

Basic Definition

Vollständiger Name: Fieldbus Network Link RS485 (Fieldbus Network Gateway)

Marke: COMSOFT (Hardware shares the same platform as Kunbus FNL series)

Positionierung: Industrial protocol conversion gateway for PROFIBUS DP ↔ Modbus TCP, compact bus bridge for DIN rail mounting

Core Model Code Explanation

FNL-RS485

FNL: Fieldbus Network Link Bus Converter

RS485: Front-end PROFIBUS physical layer interface (DB9 RS485, max. 12 Mbps DP)

2. RJ45 Ethernet Port (10/100 Mbps Auto-negotiation)

Protokoll: Modbus TCP Slave. Automatically maps PROFIBUS IO data without manual address pairing.

3. Stromversorgung: 24 VDC DIN rail power supply with industrial isolation power circuit.
4. Kernelektrik & Communication Specifications

3.1 PROFIBUS DP Side (RS485)

Baudrate: Fully compatible with 9.6 kbps ~ 12 Mbit/s

Bus Capacity: Bis zu 124 DP slaves per single master

Unterstützte Protokolle: DP Class1/Class2 Master, DPV1, DP Slave Mode

Physical Layer: Electrically isolated RS485, anti-interference industrial bus standard

3.2 Ethernet Modbus TCP Side

Hafen: 100Base-TX, native TCP/IP Socket support

Betriebsmodus: Modbus TCP Slave

Data Forwarding: DP IO and diagnostic data are automatically mapped to Modbus registers in real time, no mapping table configuration required.

Multi-Client Support: Multiple PLC/HMI host computers can access DP bus data simultaneously.

3.3 Mechanisch & Umweltspezifikationen

Montage: Standard 35 mm DIN-Schiene

Gehäuse: Green industrial flame-retardant plastic

Betriebstemperatur: 0 ℃ ~ +55 ℃

Schutzklasse: IP20 (For cabinet installation only)

HS-Zollkodex: 853810 (Industrial bus conversion module)

4. Funktionsprinzip
5. Downstream Side: As a PROFIBUS DP master, FNL-RS485 cyclically collects input/output signals and diagnostic messages from all DP slaves.
6. Internal Mapping: Hardware automatically converts DP process data and status words into standard Modbus register blocks (0x/1x/3x/4x).
7. Upstream Side: Connect to upper systems (Siemens/Mitsubishi/Omron PLCs, SCADA, touch screens) via Ethernet. Upper devices only perform Modbus TCP read/write without installing PROFIBUS drivers.
8. Reverse Write Function: Data sent via Modbus TCP is automatically forwarded to output slaves on DP bus to realize bidirectional real-time synchronization.
9. Typische Anwendungsszenarien
10. Renovation of legacy PROFIBUS production lines: Add Modbus TCP upper monitoring without modifying original DP equipment.
11. Cross-brand system interconnection: DP inverters/sensors ↔ Ethernet PLCs (Modbus TCP master).
12. Factory data acquisition: Centralize multiple DP stations and connect to SCADA & MES systems.
13. Remote equipment maintenance: Connect the Ethernet port to switches to remotely read PROFIBUS fault diagnostics.
14. Key Configuration Operations

Supporting Software: Kunbus FNL Configuration Tool (Compatible with all COMSOFT FNL series)

1. Connect PC to FNL Ethernet port via network cable and search for device IP address.
2. Configure gateway IP, subnet mask and gateway address.
3. Set PROFIBUS bus baud rate and slave address table.
4. Download parameters to the gateway and restart for activation.
5. Upper devices directly read/write Modbus registers with automatic synchronization of DP IO signals.
6. Alternative Models in the Same Series
7. FNL-ETH: Pure Ethernet DP gateway (no independent RS485 terminal, Ethernet to DP only)
8. FNL-RS232: DP to RS232 serial converter (rarely used)
9. Kunbus PR10110801: Original hardware model, fully compatible with FNL-RS485 for direct replacement.
10. Common Fault Troubleshooting Matrix

9. Beschaffung & Spare Part Information

Standard Spare Part Model: FNL-RS485 (Abbreviated as FNLRS485)

Garantie: 12 months for refurbished units, 24 months for brand-new original units

Anwendbare Branchen: Automotive production lines, Verpackungsmaschinen, Metallurgie, Wasseraufbereitung, chemical automation (mainstream PROFIBUS application sectors)

Full Application Scenarios of COMSOFT FNL-RS485

Precondition: Core Product Positioning

FNL-RS485 is a protocol conversion gateway between PROFIBUS DP Master and Modbus TCP Slave. It connects to legacy DP buses via DB9 RS485 and outputs standard Modbus TCP over Ethernet. IO mapping is automatic without manual configuration, converting DP slave data to Modbus registers. It solves three core pain points: connecting legacy DP lines to Ethernet upper systems, cross-brand system compatibility, and cloud data collection.

1. Intelligent Renovation of Production Lines (Most Common Scenario)

1.1 Upgrade Legacy PROFIBUS Lines with New Ethernet Monitoring

Massive existing equipment (Siemens S7-300/400, DP inverters, servos, encoders, Sensoren) only supports PROFIBUS, while upgraded HMI, MES and SCADA systems adopt Modbus TCP. Install FNL-RS485 to realize data interconnection without replacing original DP equipment:

Automotive welding, coating and assembly lines: Upload data from DP servos, robots and conveyor inverters to central touch screens/host computers.

Verpackung, printing and plastic extrusion equipment: Collect rotating speed, temperature and pressure from multiple DP inverters and temperature controllers in a centralized manner.

Machine tool machining centers: Integrate data from DP spindle drives and tool magazine encoders into factory monitoring systems.

Vorteile: Retain original bus wiring and equipment programs with extremely low renovation cost; one gateway supports up to 124 DP slaves.

1.2 Cross-Brand PLC System Interconnection

Two sets of control systems coexist in projects:

Untere Schicht: Siemens DP bus equipment (Wechselrichter, valve islands, Sensoren)

Obere Schicht: Ethernet PLCs only supporting Modbus TCP, such as Mitsubishi, Omron, Innovation, Delta, usw.

As a bridge, FNL-RS485 allows upper PLCs to directly read/write DP bus IO signals and fault diagnostic words without complex extra communication programming.

2. Factory Data Acquisition / MES / Energiemanagement

2.1 Centralized Collection of Full-Plant Equipment Data for MES

Deploy one FNL-RS485 per DP production line. Gateways connect to workshop switches via Ethernet, and MES servers poll all gateways through Modbus TCP to collect:

Equipment running status, start/stop signals, production counters

Inverter current, power and energy consumption data

Fault alarm codes and equipment downtime

No separate acquisition modules required for each DP device; centralized collection simplifies wiring layout.

2.2 Workshop Energy Monitoring System

DP smart meters, multi-functional power analyzers and DP pump/fan inverters upload energy consumption parameters to energy management platforms via FNL-RS485, realizing equipment/team-based energy statistics, load analysis and energy-saving optimization.

3. Process Automation Industries (Continuous Process Industry)

3.1 Wasseraufbereitung & Municipal Sewage Plants

A large number of DP water quality analyzers, flow meters, electric valves and submersible pumps are deployed on site, while central DCS/upper systems adopt Modbus TCP architecture:

Collect influent COD, pH value, liquid level and flow rate

Remotely send commands for valve opening and pump frequency adjustment

The gateway’s electrically isolated RS485 bus adapts to humid and high-electromagnetic-interference pump room environments.

3.2 Chemisch, Öl & Gas, Metallurgie, Zement

Chemische Industrie: Upload data from DP pressure/temperature transmitters, explosion-proof DP valve banks and compressor DP controllers to DCS.

Iron & Steel Metallurgy: Connect DP drive inverters of rolling lines and DP instruments of cooling systems to monitoring platforms.

Cement Building Materials: Integrate DP drive systems of kilns and fans into full-plant SCADA.

FNL-RS485 matches long-distance DP buses (hundreds of meters) to transmit data to central control rooms via Ethernet over long distances.

4. Remote Equipment Maintenance & Cloud Platform Access
5. Connect gateway Ethernet port to 4G/5G industrial routers; remote servers access workshop DP equipment via Modbus TCP.
6. Remote diagnosis for equipment manufacturers: Read DP inverter fault codes and servo operation curves, remotely adjust parameters.
7. Equipment Cloud Integration: Connect to industrial internet platforms to realize predictive maintenance, equipment life monitoring and remote after-sales service.
8. Gebäude & HVAC Cleanroom Engineering

PROFIBUS DP air dampers, chillers and temperature/humidity instruments are widely used in clean workshops and pharmaceutical air-conditioning systems:

FNL-RS485 aggregates all DP HVAC equipment

Connect to building BMS and HVAC upper computers (Modbus TCP) to automatically adjust temperature, humidity and air pressure, and count air-conditioning energy consumption

Widely applied in pharmaceutical clean workshops, electronic dust-free workshops and HVAC systems of large commercial complexes.

6. Schienenverkehr & Logistics Warehousing
7. DP control cabinets for subway/tunnel ventilation and drainage: Upload data from DP fans, water pumps and smoke detectors to integrated monitoring systems via gateways.
8. Automated warehouses & logistics sorting lines: Connect DP stackers, conveyor DP servos and scanning devices to WMS warehouse management systems to collect sorting speed, cargo position and equipment faults.
9. Auxiliary Commissioning & Testing Scenarios
10. Laboratory testing of PROFIBUS equipment: Quickly connect DP inverter and sensor prototypes to PC Modbus debugging software.
11. Equipment factory test benches: Mass performance inspection of DP equipment with unified collection of operating parameters.
12. Temporary monitoring during line commissioning: Temporarily install gateways to quickly read bus data and troubleshoot faults without modifying original PLC programs.
13. Core Advantages in All Scenarios
14. No Complex Mapping Required: DP IO and diagnostic data are automatically converted to Modbus registers without manual mapping table configuration for high debugging efficiency.
15. High Bus Capacity: One gateway supports up to 124 DP slaves, suitable for large-scale production lines.
16. Wide Baud Rate Compatibility: Full coverage of 9.6 kbps ~ 12 Mbps PROFIBUS DP, compatible with both new and legacy DP equipment for renovation projects.
17. Industrial Isolation Protection: Electrically isolated RS485 resists electromagnetic interference from motors and inverters.
18. Compact DIN Rail Design: Direct cabinet mounting without occupying excessive cabinet space.
19. Multi-Client Access: Multiple host computers, PLCs and touch screens can read data from one gateway simultaneously.

Core Product Advantages of COMSOFT FNL-RS485

1. Core Advantages of Protocol Conversion: No Manual Mapping, Higher Debugging Efficiency Than Competitors
2. Automatic Dynamic IO Mapping with Zero Register Configuration

Built-in hardware protocol parsing engine converts all process IO and DPV1 diagnostic data of PROFIBUS DP slaves to standard Modbus TCP registers in real time. No manual drag-and-drop or address assignment, saving massive configuration hours.

Ordinary domestic DP gateways require byte-by-byte IO mapping, which takes hours for large lines with dozens of slaves. FNL-RS485 enables direct Modbus read/write after bus scanning upon power-on, completing debugging within 10 Minuten.

2. Full PROFIBUS Master Capability (Full Support for Class1/Class2 + DPV1)

Beyond simple data forwarding, it supports standard cyclic DP IO exchange, acyclic parameter reading/writing, equipment diagnosis and alarm message upload. Internal parameters of inverters, servos and instruments can be read to meet deep data collection demands for equipment maintenance.

3. Concurrent Multi-Client Access via Modbus TCP

Multiple host computers, third-party PLCs, SCADA and touch screens can read/write data from one gateway concurrently. Central control, MES and local HMI collect data in parallel without occupying bus resources mutually.

2. Bus Performance Advantages: Large Capacity, Full Baud Rate Compatibility & High-Speed Communication
3. Max. 124 DP Slaves per Gateway

A single gateway covers an entire large production line, replacing multiple small conversion modules to reduce cabinet equipment quantity, simplify wiring and cut procurement & maintenance costs.

2. Full DP Baud Rate Coverage from 9.6 kbps to 12 Mbit/s

Compatible with legacy low-speed DP instruments and high-speed servo/robot DP buses, universally applicable to new and renovated lines without adjusting field device baud rates.

3. 100 Mbps Auto-Negotiation Ethernet with Low-Latency Real-Time Forwarding

Industriell 100 Mbps port synchronizes DP bus data to Modbus TCP within milliseconds, satisfying high-speed real-time data collection for transmission and assembly lines.

3. Industrial-Grade Hardware Reliability Advantages
4. Electrically Isolated DB9 RS485 Interface

Isolation circuit on DP bus side eliminates common-mode interference and ground potential difference generated by inverters and motors, ensuring stable long-term communication in humid and high-interference workshops and avoiding frequent bus dropouts and bit errors.

2. Compact Standard DIN Rail Body

35 mm universal rail mounting with small footprint, saving valuable cabinet space; 24 VDC wide-range industrial power supply adapts to unstable workshop power environments.

3. Wide-Temperature Industrial Design

Betriebstemperaturbereich: 0 ℃ ~ +55 ℃, suitable for harsh conditions including high-temperature cabinets, cold storage and outdoor equipment rooms; IP20 protection class designed for cabinet automation.

4. Native Standard DB9 PROFIBUS Interface

Directly mates standard DP plugs without terminal adapters for convenient on-site wiring; bus terminating resistors can be switched via standard DP plugs.

4. Software Configuration & Ecosystem Advantages with Outstanding Compatibility
5. Free Full Graphical Configuration Tool (CNC/Configurator II)

Visual gateway scanning, IP configuration and DP bus construction via imported GSD files; automatic bus topology generation with built-in bus diagnosis function to locate broken wires, slave faults and baud rate mismatches with one click.

2. Seamless Connection with Multi-Platform Upper Software

Supports OPC Server, perfectly compatible with SCADA/host software including WinCC, Intouch, LabVIEW, Excel and VB.

Native TCP/IP Socket interface for self-developed MES, cloud platforms and test programs, cross-compatible with Windows and Linux systems.

Compliant with FDT/DTM standard, integrable into mainstream equipment asset management software for unified full-plant equipment maintenance.

3. Standardized XML Storage for Configuration Files

Project configurations can be exported for backup and batch copied to multiple gateways for standardized deployment of multiple production lines, drastically reducing repetitive configuration work.

5. Cost Advantages for Renovation Projects
6. Zero-Modification Upgrade for Existing Production Lines

Original PROFIBUS DP equipment, wiring and PLC programs are fully retained. Only one gateway is added to connect Modbus TCP Ethernet systems without replacing inverters, valve islands or sensors, resulting in extremely low renovation investment.

2. All-in-One Bus Collection Reduces Peripheral Devices

One gateway replaces the combined solution of “DP communication card + acquisition PLC + serial server”, cutting cabinet equipment quantity, simplifying power and wiring layout and lowering potential fault points in later operation.

3. Remote Maintenance Reduces Travel Expenses

Connect Ethernet port to industrial 4G/5G routers; engineers remotely read DP equipment fault codes and parameters without on-site troubleshooting trips.

6. Differentiating Highlights Compared with Similar Gateways
7. Original German COMSOFT DP Protocol Certification with Zero Compatibility Defects

Low-cost generic gateways often suffer from missing DPV1 parameter reading and truncated long IO blocks. FNL-RS485 fully complies with PROFIBUS standards and is compatible with full series DP drive equipment from Siemens, Lenz, SEW and Danfoss.

2. Built-in Comprehensive Bus Diagnosis for Fast Troubleshooting

Real-time monitoring of bus voltage, communication messages and online slave status accurately locates offline equipment, drastically shortening downtime compared with generic gateways that only indicate communication failure.

3. Independent Hardware Gateway Without Permanent PC Drivers

Different from PC-side DP communication card solutions, the gateway operates independently without risks of system crashes or missing drivers, supporting stable 7×24-hour data collection.

7. Additional Industry-Specific Advantages

Prozessindustrie (Wasseraufbereitung & Chemicals): Isolated bus adapts to humid, high-interference pump rooms.

Automobil & Packaging Lines: High bus capacity suits dense DP stations with multiple servos and inverters.

Data Acquisition & MES: Automatic mapping shortens software integration development cycles.

OEM Equipment Matching: Compact size allows integration into equipment control cabinets as standard data upload modules.