ABB NDBU-95 63985341

The NDBU‑95 is a Fiber Optic Branching Unit provided by ABB for DCS800/DDCS systems, designed to enable fiber optic communication between a master station and up to 9 slave stations in a star topology. It can maintain normal communication of the remaining channels when the master station fails or a single slave station loses power, thereby enhancing the reliability and fault tolerance of the system.

Main Technical Parameters

• Number of Channels: 1 master channel + 9 slave channels
• Transmission Rate: 1–4 MBd (fiber optic rate is programmable)
• Drive Current: 20 mA, 30 mA, 50 mA optional, maximum input current is approximately 300 mA
• Power Supply: +24 V DC, with a tolerance of ±10%
• Operating Temperature: 0 °C – 50 °C
• Protection Class: IP67 (dustproof and waterproof)
• Dimensions: Approximately 264 mm × 84 mm × 50 mm (L × W × H)
• Indicator Lights: Each channel is equipped with a green LED to display data reception status

Product Features

1. High Reliability: The star topology ensures that a single point of failure does not affect the entire network.
2. Compact and Robust: The metal housing with IP67 protection class is suitable for harsh industrial environments.
3. Easy Installation and Configuration: Adopts standard M12×1 electrical connections and G 1/2″ process interfaces, supporting quick wiring.
4. Multi-Protocol Compatibility: Compatible with common industrial communication protocols such as ControlNet, Ethernet, Modbus, and Profinet.
5. Programmability: Transmission rate, drive current, and channel functions can all be configured via software.
6. Smart Performance: Delivers intelligent signal management for stable industrial communication.

Structure and Composition

• Fiber Optic Adapter Module: Responsible for the transmission and reception of optical signals as well as electrical isolation.
• Channel Board: Each channel is equipped with an independent LED indicator, drive circuit, and address register.
• Power Supply Module: Provides stable +24 V DC power and has overcurrent protection.
• Case and Mounting Bracket: The metal housing is matched with DIN rail or panel mounting holes for easy fixation inside the control cabinet.

Typical Application Fields

1. Industrial Automation: Distributed control of drive systems, frequency converters, and servo systems.
2. Process Control: Fieldbus networks for continuous production processes in chemical, petroleum, metallurgical, and other industries.
3. Energy Management: Real-time monitoring and control of power plants and distribution automation systems.
4. Large-Scale Machinery: High-speed data acquisition and command issuance for CNC machine tools, printing and packaging equipment.