ABB REA101-AA RLY-REA101-AAAG Arc Protection Relay – Obsolete RELION Spare Part

Technical Dossier

Product Details And Specifications

ABB REA101-AA RLY-REA101-AAAG Arc Protection Relay – Obsolete RELION Spare Part

When an arc protection relay fails in a live medium-voltage switchgear panel, the consequences extend far beyond a single component replacement. A full panel upgrade — including engineering assessment, new IED commissioning, protection coordination studies, and production downtime — routinely costs plant operators between $200,000 and $1,500,000 USD per incident. The ABB REA101-AA (catalog reference RLY-REA101-AAAG) has been discontinued by ABB, and sourcing a verified replacement unit from the secondary market is the only path that avoids that capital expenditure. DriveKNMS maintains physical stock of this relay and ships globally to facilities that cannot afford to wait.

Technical Specifications

Note: Electrical parameters such as input voltage range, trip time, and I/O configuration vary by installation. DriveKNMS does not publish unverified specifications. Contact us with your panel documentation for a compatibility confirmation before ordering.

Solving the Discontinued Hardware Crisis

The REA101-AA was designed specifically for arc flash detection in ABB's medium-voltage switchgear ecosystem. It operates as a dedicated arc protection unit — not a general-purpose relay — which means there is no off-the-shelf modern equivalent that installs without engineering rework. Facilities running ABB MNS or UniGear switchgear built between the late 1990s and early 2010s are the primary users of this relay. These panels were engineered around the REA101-AA's specific trip logic, fiber-optic arc sensor inputs, and communication interfaces. Replacing the relay with a current-generation IED requires new wiring, updated protection coordination studies, and in many jurisdictions, a formal re-commissioning inspection — a process that takes months and carries significant regulatory risk.

The economic case for sourcing a verified REA101-AA from the secondary market is straightforward: a single unit extends the operational life of an entire switchgear assembly by 5 to 10 years, deferring a capital project that most maintenance budgets are not structured to absorb. For plant managers operating under asset-sweating mandates, this is not a workaround — it is a documented maintenance strategy used by utilities and industrial operators worldwide.

Facilities that have successfully extended the life of legacy ABB switchgear through secondary-market spare procurement typically follow a structured approach: they identify the three to five components with the highest failure probability, secure buffer stock of each, and establish a documented inspection cycle. The REA101-AA, as the primary arc protection device, sits at the top of that list. A single unplanned failure without a spare on hand forces an emergency shutdown and accelerates the timeline for a full panel replacement that may not have been budgeted for another five years.

Condition & Reliability Assurance

DriveKNMS applies a five-step quality process to every discontinued relay before it is offered for sale:

• Visual and mechanical inspection: Housing integrity, terminal condition, and label verification against the original ABB part number.
• Electrolytic capacitor assessment: Capacitors are among the first components to degrade in stored electronics. Units showing signs of capacitor aging are quarantined and not offered as functional spares.
• Firmware version verification: Where accessible, firmware revision is documented and disclosed to the buyer prior to shipment.
• Pin and connector corrosion check: All I/O terminals and communication ports are inspected under magnification. Corroded or mechanically compromised connectors are flagged.
• Functional bench test: Units are powered and tested against known-good reference behavior before being classified as serviceable stock.

Units that do not pass all five stages are not sold as functional spares. Condition grade is disclosed on every order confirmation.

Key Features for System Maintenance

• Drop-in replacement: The REA101-AA installs directly into the original panel cutout and terminal block without mechanical modification.
• No reprogramming required: Protection settings stored in the original relay are not held in the replacement unit — your protection engineer will need to re-enter the existing coordination settings, but no new engineering study is required if the settings are documented.
• Avoids engineering rework costs: Unlike a modern IED substitution, this replacement does not trigger a protection coordination review or re-commissioning requirement in most jurisdictions.
• Immediate dispatch: Stock units ship within 2 business days of order confirmation. Export documentation for international shipments is prepared as standard.

FAQ

What warranty applies to a discontinued relay?
DriveKNMS provides a 90-day functional warranty on all tested spare units. The warranty covers failure under normal operating conditions and excludes damage caused by incorrect installation or out-of-specification electrical events.

How do I know the unit is genuine ABB and not a counterfeit?
Every unit is inspected against ABB's original labeling standards, including part number format, date codes, and housing markings. We do not source from unverified channels. Documentation of the unit's provenance is available on request.

Should I buy more than one unit?
For facilities with multiple panels using the REA101-AA, holding a minimum of two buffer units is standard practice. As secondary market stock depletes globally, lead times for this part will increase. Procurement teams managing long-term maintenance plans should treat this as a time-sensitive decision.

Can you source additional units if I need more than you have in stock?
Yes. DriveKNMS operates an active sourcing network for discontinued ABB components. Contact us with your quantity requirement and we will provide a sourcing timeline and price indication within 48 hours.