ABB REA107 Arc Protection Relay Modules REA107-AA, RLY-REA107-AAA

Technical Dossier

Product Details And Specifications

ABB REA107 Series Technical Notes

The ABB REA107 is a dedicated arc protection relay platform developed by ABB (formerly Strömberg/ABB Oy, Finland) for medium-voltage switchgear and distribution systems. It is deployed across high-criticality industrial environments including chemical processing plants, nuclear auxiliary power systems, offshore platforms, and petroleum refineries. The REA107 series detects arc flash events using optical sensor technology combined with overcurrent supervision, enabling trip times typically below 10 ms — a performance benchmark that has made it a reference design in IEC 62271-compliant switchgear installations globally.

The platform is engineered for panel-mount installation in MV switchgear cubicles and integrates directly with bay-level protection schemes. Its modular I/O architecture allows configuration for single-zone or multi-zone arc detection, making it scalable from simple feeder panels to complex busbar protection topologies. The REA107 series is widely specified in engineering procurement documents for substations rated 6 kV to 36 kV.

The Evolution of REA107 Architecture

The REA107 platform was introduced as part of ABB's SPACOM/REA protection relay family, succeeding earlier electromechanical arc detection schemes. The original REA101 and REA103 units established the optical arc detection methodology; the REA107 extended this with integrated overcurrent element supervision and expanded I/O capacity for multi-feeder applications.

Key architectural milestones:

REA107 Full Catalog & Functionalities (SKU List)

The following SKUs represent the documented REA107 series module range. Each entry reflects a distinct hardware configuration or accessory role within the platform:

Arc Detection & Main Relay Units

• REA107-AA: Single-zone arc protection relay, optical + overcurrent supervision, panel-mount
• REA107-AB: Single-zone arc relay with extended binary input capacity for multi-feeder schemes
• REA107-BA: Dual-zone arc protection relay, independent zone tripping, 2× optical sensor inputs
• REA107-BB: Dual-zone relay with enhanced I/O, suitable for double-busbar switchgear
• REA107-CA: Three-zone arc protection relay for ring-bus or complex MV topologies

Relay Output Expansion Modules

• RLY-REA107-AAA: Auxiliary relay output module, 4× NO/NC contacts, plug-in to REA107 base unit
• RLY-REA107-ABA: Relay output module with high-speed contacts rated for capacitor trip duty
• RLY-REA107-BAA: Extended relay output card, 8× output contacts, for multi-circuit trip applications

Sensor & Fiber Interface Modules

• LPIO-REA107-A: Light point I/O interface card, connects up to 8 optical arc sensors per zone
• LPIO-REA107-B: Extended LPIO card with loop sensor support for cable compartment protection
• SEN-REA107-OPT: Optical fiber arc sensor, point-type, for busbar compartment installation
• SEN-REA107-LOOP: Loop-type arc sensor, 2 m detection length, for cable compartment arcs

Power Supply & Auxiliary Components

• PSU-REA107-24V: 24 VDC auxiliary power supply module for REA107 panel assemblies
• PSU-REA107-110V: 110 VDC/VAC power supply input module, substation battery-compatible
• PSU-REA107-220V: 220 VDC/VAC power supply input module for high-voltage substation auxiliaries

Communication & Testing Accessories

• COM-REA107-SER: Serial communication adapter for SCADA/event logging integration
• TST-REA107-KIT: Functional test kit for optical sensor channel verification and relay output testing

Sourcing Hard-to-Find & Obsolete REA107 Parts

The REA107 series has entered the end-of-active-production phase. ABB has transitioned its arc protection portfolio to the TVOC-2 and VAMP 321 platforms. However, a significant installed base of REA107 units remains operational in substations and MV switchgear panels with design lifetimes extending to 2035 and beyond. Replacement of the entire protection scheme is not always economically or operationally feasible, creating sustained demand for original REA107 spare modules.

Quality Control for the REA107 Range

The REA107 platform presents specific quality verification challenges due to its optical detection circuitry and high-speed relay output requirements. DriveKNMS applies a structured test protocol for every REA107 unit processed:

• Optical channel sensitivity test: Each optical sensor input is stimulated with a calibrated light pulse (wavelength and intensity per ABB REA107 technical specification). Detection threshold and response time are recorded and compared against factory specification.
• Overcurrent supervision check: The integrated overcurrent element is tested at 50%, 100%, and 150% of rated pickup current to verify correct operation and coordination with the optical channel.
• Relay output contact test: All NO/NC output contacts on the base unit and RLY expansion modules are tested for contact resistance (100 MΩ at 500 VDC), and operate/reset timing.
• Auxiliary power supply verification: Input voltage range, output regulation, and ripple are measured across the full specified input range (e.g., 80–265 VAC for universal PSU variants).
• Backplane and connector inspection: Edge connectors and inter-module bus contacts are cleaned, inspected under magnification, and re-tensioned where applicable.
• Burn-in: Units are powered for a minimum of 24 hours at rated voltage before final test to screen for early-life component failures.