CC-Link IE to Profinet Gateway for Industrial Data Collection
In modern industrial automation, multi-vendor PLC systems often coexist within the same facility. A common challenge arises when a Siemens S7-1200 controller on Profinet needs to exchange data with a Mitsubishi FX5U PLC running CC-Link IE Field Basic. Without a proper bridge, these systems become isolated data islands, forcing manual intervention and reducing overall efficiency. This article explores how a dedicated protocol conversion gateway can solve this problem, using a real-world boiler house upgrade as an example.
The Challenge: Two Networks, One Goal
A thermal power plant in East China added a new 2×50 t/h circulating fluidized bed boiler house. The main control system was built around a Siemens SIMATIC S7-1200 (CPU 1215C AC/DC/Rly, order number 6ES7 215-1HG40-0XB0), managing combustion, drum level, and safety interlocks via Profinet. Later, environmental upgrades introduced auxiliary systems—baghouse dust collectors, pneumatic ash conveying, and water softening skids—controlled by a Mitsubishi MELSEC FX5U-64MT/ES using CC-Link IE Field Basic. Although each PLC worked perfectly on its own, they couldn’t communicate. The SCADA system (WinCC) couldn’t read auxiliary temperatures, pressure differentials, or ash conveying cycles. Operators had to manually start feeders based on boiler load, and maintenance teams needed both TIA Portal and GX Works3 software, slowing down troubleshooting.
The plant’s requirements were strict: no boiler shutdown, no PLC program changes, and completion within one day. The solution was an industrial protocol conversion gateway acting as a transparent bridge between CC-Link IE Field Basic and Profinet.
Network Topology and Data Flow
The existing setup included a Siemens Scalance XB208 switch in the main cabinet, with the Profinet network on subnet 192.168.1.0/24. The auxiliary remote I/O box housed the FX5U PLC on CC-Link IE FB subnet 192.168.2.0/24. The gateway was installed between these two networks:
- Profinet port (RJ45-1): Connected to the XB208 switch, assigned IP 192.168.1.126.
- CC-Link IE FB port (RJ45-2): Directly connected to the FX5U built-in Ethernet port, assigned IP 192.168.2.126.
- Power: 24 VDC from a redundant Phoenix QUINT-PS/1AC/24DC/10A power supply.
The gateway functioned as a transparent bridge. On the Profinet side, the S7-1200 saw the FX5U as a 32-byte input and 32-byte output IO device. On the CC-Link IE FB side, the FX5U treated the gateway as station number 1, occupying 64 points of RWw (write) and 64 points of RWr (read).
Key Hardware Components
Step-by-Step Implementation Without Downtime
The entire integration was completed in one day without stopping the boiler. Here’s how:
Preparation
A 110 mm wide slot was reserved on the 35 mm DIN rail in the cabinet. The gateway’s GSDML file (e.g., “GSDML-V2.35-YC-PN-CCLKIE-20251007.xml”) was installed in TIA Portal V18 beforehand.
Hardware Connection
Only the auxiliary 24 VDC circuit was powered off—boiler operation continued. Shielded Cat5e cables (1 m and 2 m) connected the gateway ports. After power-up, the PWR LED stayed solid, PN LED flashed quickly, and CCLKIE LED flashed slowly, indicating physical layer readiness.
Gateway Configuration
Using the vendor’s configuration tool (e.g., YCConfig V3.1.2), the gateway was scanned and identified by its serial number. Settings applied:
- Profinet tab: Device name “PN-CCLKIE-Boiler01”, IP 192.168.1.126, 32 bytes input, 32 bytes output.
- CC-Link IE tab: Station number 1, RWw/RWr each 32 words, linear mapping.
After downloading, both PN and CCLKIE LEDs turned solid, confirming protocol stacks were running.
Siemens Side Configuration
In TIA Portal, the gateway was added as a Profinet IO device under the S7-1200 network. It automatically assigned input addresses IB100–IB131 and output addresses QB100–QB131. After compilation and download, the CPU reported no errors, and the diagnostic buffer showed “IO device PN-CCLKIE-Boiler01 available”.
Mitsubishi Side Configuration
In GX Works3, under CC-Link IE FB detailed settings, a new station was added: station 1, 64 points RWw, 64 points RWr. The mapping was:
- RWw0–31 → D1000–D1031 (data written to gateway, i.e., Siemens inputs)
- RWr0–31 → D2000–D2031 (data read from gateway, i.e., Siemens outputs)
After writing to the PLC and resetting, FX5U’s SD10610 (station status) changed from 0 to 1, confirming communication.
Commissioning and Validation
Several tests were performed:
- Analog value test: FX5U wrote 16#1234 to D1000; S7-1200 immediately showed 16#1234 at IB100–IB101, with a round-trip delay of 8 ms.
- Digital signal test: FX5U set M1000; the gateway mapped it to IB106.0, and WinCC updated within 1 second.
- Load interlocking: S7-1200 logic: when steam flow >38 t/h and baghouse differential pressure <1200 Pa, QB112.0 was set. The gateway forwarded this to FX5U's M812, automatically starting the feeder—no manual intervention.
- Fail-safe test: Disconnecting either network cable triggered a diagnostic bit within 300 ms. S7-1200 called OB82 to log the event, and FX5U’s M815 alarmed, ensuring safe shutdown.
After 4 hours of continuous testing with zero packet loss or signal jumps, the project was accepted on the first attempt.
Performance and Benefits
The gateway delivered impressive results:
- Data refresh cycle: Profinet 4 ms + gateway 2 ms + CC-Link IE FB 2 ms = ≤10 ms total.
- Communication reliability: >99.997% success rate over 30 consecutive days.
- Maintenance efficiency: Monthly inspection reduced from 4 people × 2 hours to 1 person × 0.5 hours.
- Energy savings: Automatic feeder start/stop based on load reduced electricity consumption per ton of steam by 1.8%, saving approximately $25,000 annually.
Key Takeaways for Protocol Integration
This case demonstrates that heterogeneous industrial networks can be unified quickly and cost-effectively. A protocol gateway eliminates data silos, preserves existing investments, and lays the foundation for future MES or energy management system integration. When selecting a gateway, consider these factors:
- Real-time performance: Look for deterministic latency under 10 ms for control-critical data.
- Ease of configuration: GSDML support and intuitive mapping tools reduce engineering time.
- Robustness: Industrial-grade design with wide temperature range and redundant power inputs.
- Diagnostics: Built-in status LEDs and diagnostic bits simplify troubleshooting.
By bridging CC-Link IE Field Basic and Profinet, plants can achieve seamless data exchange, improve automation levels, and reduce operational costs—all without disrupting existing processes.
Note: The hardware models and performance figures mentioned are based on typical industrial applications. Actual results may vary depending on network load and configuration. Always refer to the manufacturer’s documentation for specific installation guidelines.
