Siemens 6FC5110-0BB04-0AA1 Sinumerik 840C NC-CPU

The Siemens 6FC5110-0BB04-0AA1 is an NC-CPU (Numerical Control Central Processing Unit) for the Sinumerik 840C CNC system. This high-performance controller is based on a 486DX4 processor running at 100 MHz and includes 4 MB of RAM. It executes part programs, interpolates axes, and manages the integrated PLC (Programmable Logic Controller) for machine tool functions. The 840C is a legacy CNC system widely used in milling machines, lathes, machining centers, and grinding machines. The CPU module is installed in the 840C main rack and communicates with servo drives, I/O, and operator panels.

Technical Specifications

Processor: Intel 486DX4, 100 MHz. RAM: 4 MB (expandable to 8 MB). Flash memory: 2 MB for system software. Interface: NC bus (SINEC L2-DP), serial ports (RS-232). Power supply: 5V DC from backplane, 3 A max. Dimensions: 300 mm × 140 mm × 40 mm. Weight: 1.2 kg. Operating temperature: 0°C to 50°C. Storage: -20°C to 60°C. The module includes status LEDs (RUN, STOP, FAULT) and a 7-segment display for diagnostic codes. It is compatible with Sinumerik 840C software version 3 and above.

Key Features

• High-speed 486DX4 CPU for complex contouring

• Controls up to 8 axes and 2 spindles

• Integrated PLC functionality for auxiliary machine control

• Built-in NC bus (SINEC L2-DP) for drive communication

• RS-232 interface for part program upload/download

• LED diagnostic codes for troubleshooting

Applications

The 6FC5110-0BB04-0AA1 is used as the central processing unit in Sinumerik 840C-controlled machine tools. It executes G-code programs, performs linear and circular interpolation, and coordinates tool changes, coolant, and other auxiliary functions. It is essential for maintaining legacy CNC machinery.

Installation

Insert the CPU into the 840C rack (e.g., 6FC5210) using the card guides. Ensure the backplane connectors align. Secure with screws. Connect the NC bus cable to the module. Set the hardware address using DIP switches. The module automatically runs system software when powered on. If the system is configured for multi-CPU, set the master/slave jumpers accordingly.

Maintenance and Troubleshooting

The CPU has no user-serviceable parts. The 7-segment display shows diagnostic codes during boot; refer to the Sinumerik 840C manual for code meanings. Common issues: battery failure (replace battery on motherboard), bad RAM (memory test errors), or corrupted firmware (requires reflashing). Replace the module if faulty.

Conclusion

The Siemens 6FC5110-0BB04-0AA1 is a powerful NC-CPU for Sinumerik 840C systems, providing motion control and PLC integration for industrial machine tools. It is a key component for maintaining and repairing legacy CNC equipment.