ABB SPAJ140 C Combined Overcurrent and Earth-Fault Protection Relay

Description

Technical Specifications

• Product Type: Microprocessor-based combined overcurrent and earth-fault relay
• Protection Functions:
  • Three-phase low-set phase overcurrent (definite time or IDMT characteristic)
  • Three-phase high-set phase overcurrent (instantaneous or definite time)
  • Low-set non-directional earth-fault (definite time or IDMT characteristic)
  • High-set non-directional earth-fault (instantaneous or definite time)
  • Built-in circuit-breaker failure protection
• Time-Current Curves: Four standard IDMT curves (IEC/BS), plus RI and RXIDG specific inverse-time characteristics
• Input Current Ratings: 1 A or 5 A (CT secondary)
• Auxiliary Power Supply: Wide-range DC (24–250 V DC) or AC (100–240 V AC, 50/60 Hz)
• Output Relays: 2 heavy-duty tripping relays + 4 light-duty signaling relays (configurable matrix)
• Communication Interface: Serial port for local/remote access to parameters, fault logs, and diagnostics
• Display: Numerical readout for measured values, settings, fault records, and status codes
• Self-Supervision: Continuous hardware/software monitoring with auto-diagnosisABB
• Operating Temperature: -10°C to +55°C
• Humidity: 5%–95% RH (non-condensing)
• Protection Degree: IP54 (aluminum case for harsh/offshore environments)
• Certifications: IEC 60255, CE, UL, and marine/offshore compliance
• Mounting: Panel-mounted or rack-mounted
• Dimensions: Standard industrial form factor (approx. 144 mm × 144 mm × 220 mm)
• Weight: Approx. 3.5 kg

Key Features

Integrated Multi-Protection Design

• Combined Functionality: Integrates phase overcurrent, earth-fault, and breaker failure protection in one unit, reducing panel space and wiring complexityABB.
• Dual Protection Stages: Each protection function includes low-set (back-up) and high-set (instantaneous) stages for selective coordination.
• Flexible Time Characteristics: Supports both definite time and multiple IDMT curves for precise protection coordination in complex networks.

Advanced Communication & Configuration

• Serial Connectivity: Built-in serial port enables remote parameter setting, fault data retrieval, and integration with SCADA/automation systems.
• Local/Remote Operation: Full control via front-panel keypad/display or portable PC software.
• Fault Memory: Records fault parameters, current values, and event logs for post-fault analysis.

Robust Reliability & Diagnostics

• Continuous Self-Supervision: Monitors microprocessor, power supply, and I/O circuits; alerts on internal faultsABB.
• High Electromagnetic Immunity: Designed to withstand industrial EMI, ensuring stable operation in substations.
• IP54 Enclosure: Dust and water-resistant aluminum housing for offshore and harsh industrial sites.

Flexible Output & Control

• Configurable Relay Matrix: Outputs can be freely assigned to trip, alarm, or status signals.
• External Control Input: Accepts blocking signals, remote reset, or setting selection via terminal 10–11.
• Visual Indicators: LED and numerical display for real-time status, fault codes, and measured values.

Application Scenarios

Medium-Voltage Distribution Networks

• Radial Feeders: Primary protection for overhead lines and cables in urban/rural distribution gridsABB.
• Substation Feeders: Selective protection in distribution substations with solid/resistance/impedance groundingABB.
• Distribution Transformers: Backup overcurrent and earth-fault protection for distribution transformers.

Industrial Power Systems

• Oil & Gas Facilities: Protection for pumps, compressors, and process loads in refineries and offshore platforms.
• Mining Operations: Reliable protection for heavy machinery and conveyor systems in underground mines.
• Manufacturing Plants: Overcurrent/earth-fault protection for motor control centers and industrial distribution boards.
• Marine & Offshore: IP54-rated units for shipboard power distribution and offshore platform protection.

Infrastructure & Utilities

• Water & Wastewater: Protection for pump stations and treatment plant electrical systems.
• Renewable Energy: Grid interconnection protection for wind farms and solar power plants.
• Railway Electrification: Feeder protection for DC/AC traction power supply systems.

Legacy System Retrofits

• Substation Modernization: Upgrading electromechanical relays with microprocessor-based SPAJ140 C for improved selectivity and diagnostics.
• System Expansion: Adding protection to existing distribution networks without major rewiring.