ABB REA101-AAA | REA Series Relay, Genuine Replacement

Key Technical Specifications

• Model: REA101-AAA
• Brand: ABB
• Product type: Arc fault protection relay
• Series: REA 101
• Application: Medium- and low-voltage switchgear protection
• Operating mode: Stand-alone or with extension modules
• Compatible extensions: REA 103, REA 105, REA 107
• Sensor inputs: Optical sensor based arc detection
• Outputs: High-speed trip outputs and relay output
• Self-monitoring: Built-in supervision
• Front protection: Transparent sealed front cover, IP54
• Communication / wiring details: Verify in OEM datasheet

Product Introduction

ABB REA101-AAA is the main module of the REA 101 arc fault protection system for medium- and low-voltage switchgear. It is used where fast arc detection and rapid trip action matter more than general-purpose relay flexibility.

In field replacement work, this unit usually goes into existing ABB protection schemes, so interface fit matters as much as the protection logic. The system is designed around optical sensing and fast tripping, and the exact sensor arrangement, wiring, and extension compatibility should be confirmed against the OEM manual before swap.

Key Selling Points & Differentiators

• Designed for arc fault protection in switchgear, not as a general relay.
• Works stand-alone or with REA 103, REA 105, and REA 107 extension modules.
• Optical sensor detection and high-speed trip outputs are the core value points for arc mitigation.
• Built-in self-supervision helps catch wiring or sensor issues before they become blind spots.
• We can support incoming inspection, label and serial review where available, functional verification, and final QC packaging with a test note.
• Compared with a conventional overcurrent relay, this unit adds light-based arc detection for faster clearing in the right application.
• Not recommended for install unless the sensor type, wiring, and trip scheme match the existing panel design.
• Verify the OEM manual and protection coordination study before putting it back into service; arc protection should follow the documented test method and switching sequence.