ABB SPAU Series Protection Relays: SPAU130C-AA Specs, Models & Availability

Technical Dossier

Product Details And Specifications

ABB SPAU Series: Comprehensive Module Range and Technical Overview

The ABB SPAU series comprises a family of numerical protection relays engineered for voltage, current, and frequency protection in medium-voltage distribution networks. Deployed extensively in chemical plants, oil refineries, nuclear auxiliary systems, and heavy industrial substations, SPAU relays operate as standalone protection units or integrate into ABB's MicroSCADA and SPACOM communication architectures. Their modular hardware design, standardized COMBIFLEX relay base, and serial SPA-bus communication protocol have made them a reference standard in utility and industrial protection engineering since the early 1990s. Installed base globally exceeds hundreds of thousands of units, with active deployments still recorded in European, Middle Eastern, and Asian grid infrastructure.

The Evolution of SPAU Series Architecture

The SPAU series was introduced by ABB (then ABB Strömberg) in the late 1980s as part of the broader SPACOM numerical relay platform. First-generation units such as the SPAU110C and SPAU120C established the core hardware architecture: a front-panel LCD display, a rear-terminal COMBIFLEX base, and an SPA-bus RS-485 serial port for SCADA integration. These early models used EEPROM-based parameter storage and offered fixed protection function sets.

Through the 1990s, ABB expanded the series with enhanced models including the SPAU130C, SPAU140C, and SPAU160C families, adding configurable output relays, improved measurement accuracy (class 0.5 metering), and extended communication diagnostics. The SPAU240C and SPAU341C introduced multi-function protection combining voltage, frequency, and directional elements in a single chassis, reducing panel footprint in retrofit projects.

By the 2000s, the SPAU series entered its mature phase. ABB's successor platform — the REF, RET, and REU series under the Relion® product line — began replacing SPAU in new installations. However, the SPAU series remains in active service across legacy substations where full panel replacement is not economically viable. ABB and authorized distributors continue to supply spare units and repair services to support long-term maintenance contracts extending to 2030 and beyond.

Compatibility note: SPAU relays use the SPA-bus protocol (not IEC 61850). Integration with modern IEC 61850 SCADA systems requires an SPA/IEC 61850 protocol converter gateway.

SPAU Series Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly stocked models within the ABB SPAU series. Each unit is classified by primary protection function.

Voltage Protection

• SPAU110C: Three-phase undervoltage and overvoltage relay, fixed thresholds, SPA-bus output.
• SPAU120C: Three-phase voltage relay with independent U> and U< stages, COMBIFLEX base.
• SPAU121C: Enhanced voltage relay with additional neutral voltage displacement (U0) measurement.
• SPAU122C: Voltage relay with integrated event recorder and disturbance memory, 8 output relays.
• SPAU130C-AA: Three-phase voltage relay; monitors phase-to-phase and phase-to-neutral voltages; two independent setting groups; SPA-bus communication; COMBIFLEX mounting.
• SPAU131C: Voltage relay with extended measurement range for 110 kV applications via VT input scaling.

Current & Overcurrent Protection

• SPAU140C: Three-phase overcurrent and earth-fault relay; IDMT and definite-time characteristics; SPA-bus.
• SPAU141C: Overcurrent relay with directional earth-fault element; suitable for compensated networks.
• SPAU142C: High-impedance differential protection relay for busbar and reactor applications.
• SPAU143C: Overcurrent relay with thermal overload model; motor and cable protection.
• SPAU144C: Combined overcurrent and voltage relay; dual-function protection in single chassis.

Frequency Protection

• SPAU148C: Frequency relay; under/overfrequency protection with df/dt rate-of-change element; load shedding applications.

Multi-Function & Combined Protection

• SPAU160C: Voltage and frequency combined relay; six independent protection stages; substation automation integration.
• SPAU161C: Extended multi-function relay with additional I/O for complex interlocking schemes.
• SPAU240C: Directional overcurrent and earth-fault relay; two-winding transformer feeder protection.
• SPAU341C: Three-phase voltage, current, and frequency relay; comprehensive feeder protection; dual SPA-bus ports.

Sourcing Hard-to-Find & Obsolete SPAU Series Parts

The SPAU series was officially discontinued from ABB's active production catalog in the 2010s. Standard ABB distribution channels no longer carry new stock for most models. DriveKNMS maintains a dedicated inventory of new-surplus, refurbished, and tested-used SPAU units sourced from decommissioned substations, OEM overstock, and authorized secondary market channels.

For plant operators running SPAU-based protection panels, DriveKNMS provides: (1) direct unit replacement with identical model numbers to avoid relay coordination recalculation; (2) cross-reference sourcing where an exact model is unavailable, identifying functionally equivalent SPAU variants with compatible terminal assignments; (3) long-term supply agreements for utilities requiring guaranteed stock availability over multi-year maintenance windows.

All units are shipped with full traceability documentation. Export compliance is handled for shipments to the EU, Middle East, Southeast Asia, and the Americas.

Quality Control for the SPAU Series Range

SPAU relays incorporate a COMBIFLEX plug-in base with a multi-pin rear connector. Connector pin oxidation, output relay contact wear, and EEPROM parameter corruption are the primary failure modes identified in aged units. DriveKNMS applies the following test protocol to all SPAU units prior to dispatch:

• Visual inspection: PCB corrosion check, capacitor condition assessment, front-panel display pixel verification.
• Power-on self-test: Unit powered at rated auxiliary voltage (48 VDC / 110 VDC / 220 VDC as applicable); internal self-diagnostic pass confirmed.
• Protection function test: Injection of calibrated AC voltage/current signals via test set; verification of pickup thresholds, time delays, and output relay operation against factory specification.
• SPA-bus communication test: Serial communication verified using SPA-bus master simulator; parameter read/write and event reporting confirmed.
• Output relay contact resistance: Measured with micro-ohmmeter; contacts replaced if resistance exceeds 100 mΩ.
• Final calibration check: Measurement accuracy verified against class 0.5 metering standard.

Test records are retained and available upon request for each dispatched unit.