Description
The ABB RER103 is a Bus Connection Module designed for ABB RE_500 series protection and control devices. It provides an interface between the host device and a fiber-optic LON® or SPA bus, converting optical communication signals to electrical RS-485 signals and vice versa.
The module plugs into the 9-pin D-type connector on the rear of a compatible RE_500 device. It is powered directly through the host device connector and includes a Service Pin for LON node commissioning.
🔧 Key Features
• ABB RE_500 series bus connection module
• Fiber-optic LON® / SPA communication interface
• Optical-to-RS-485 signal conversion
• Supports SPA bus communication
• Supports LON® bus communication
• LON collision detection
• Integrated Service Pin for LON nodes
• Rear-panel 9-pin D-type connection
• Compact PCB housed in a plastic enclosure
• Four optical interface variants available
📋 Product Datasheet
• Brand: ABB
• Model: RER103
• Product Type: Bus Connection Module
• System: ABB RE_500 Series
• Main Function: Fiber-Optic Bus Interface
• Communication: LON® / SPA
• Electrical Interface: RS-485
• Host Connection: 9-pin D-type connector
• Power Supply: From host device via D-type connector
• Service Function: LON Service Pin
• Protocol Selection: Determined by host-device CD signal
• Optical Variants: Plastic/Plastic, Plastic/Glass, Glass/Plastic, Glass/Glass
• Mounting: Rear-panel plug-in installation
• Dimensions: Approx. 75 × 50 × 25 mm*
• Weight: Approx. 0.1 kg*
• Operating Temperature: System dependent*
• Country of Origin: Sweden*
The ABB technical documentation identifies four ordering variants: RER103-BB, RER103-BM, RER103-MB, and RER103-MM, depending on the transmitter and receiver optical-fiber type.
🏭 Typical Applications
The RER103 is suitable for:
• Substation automation
• Protective relay systems
• Feeder protection
• Power distribution automation
• ABB RE_500 protection equipment
• LON® communication networks
• SPA bus communication networks
⚡ Functional Description
When operating in SPA mode, signals received through the fiber-optic interface are passed to the RS-485 interface and transmitted through the optical interface as required.
When operating in LON mode, the RER103 provides the optical-to-RS-485 interface and supports collision detection. The host device determines whether the module operates in LON or SPA mode through the CD signal.
🔌 Installation & Configuration
Basic installation procedure:
• Confirm the host device is compatible with RER103
• Verify the correct optical variant
• Insert the module into the 9-pin D-type connector
• Connect the incoming optical fiber to Rx
• Connect the outgoing optical fiber to Tx
• Confirm the host-device communication configuration
• Check the communication link after startup
For fiber installation, avoid excessive bending, contamination, or mechanical stress on the optical connectors.
🛠️ Replacement Notes
Before ordering, verify:
• Complete model RER103
• Optical transmitter type
• Optical receiver type
• Existing fiber type
• Host RE_500 device
• Required communication mode: LON or SPA
• Connector arrangement
The BB/BM/MB/MM suffix is important because it identifies the transmitter and receiver fiber types. Do not substitute these variants solely because the basic model number is the same.
📦 Ordering Information
ABB RER103 | Bus Connection Module | LON / SPA Fiber-Optic Interface | RS-485 | RE_500 Series
