REF543KB127AAAA: Product OverviewThe REF543KB127AAAA is a multifunction feeder protection relay from ABB’s Relion® 543 series, designed for comprehensive protection and control of distribution feeders in utility substations and industrial power systems. This advanced electronic relay serves as the primary protection device for medium-voltage feeders, safeguarding against electrical faults and abnormal operating conditions that could damage equipment or disrupt power supply. Installed in switchgear panels or control cabinets, it continuously monitors electrical parameters including phase currents, earth-fault current, voltage, frequency, and power to detect fault conditions and initiate appropriate protective actions.The relay incorporates multiple protection functions specifically designed for feeder applications, including directional and non-directional overcurrent protection, earth-fault protection, thermal overload protection, and auto-reclosing functionality. Beyond protection, it provides extensive control functions such as circuit breaker control, interlocking, and measurement capabilities for comprehensive feeder management. The device features advanced communication capabilities for integration into modern substation automation systems, allowing for remote monitoring, control, and data acquisition.
•• Control Functions: Circuit breaker control, interlocking
•• Measurement: V, I, P, Q, PF, Frequency, Energy
•• Communication Protocols: IEC 61850, Modbus RTU/TCP, DNP3.0
•• Communication Ports: Ethernet, RS485
•• Display: Graphical LCD with user interface
•• Power Supply: 24-48 VDC / 48-250 VAC/DC
•• Operating Temperature: -25°C to +70°C
•• Certifications: UL, CE, IEC 60255
ABB REF543KB127AAAA
Core Features & Customer ValueThe relay’s comprehensive protection suite eliminates the need for multiple discrete protective devices, reducing panel space, wiring complexity, and overall system cost. For protection engineers, this integration simplifies coordination studies and testing procedures. The high-accuracy measurements and advanced algorithms provide faster and more selective fault detection compared to electromechanical relays, minimizing equipment damage and reducing outage times during faults.The integrated auto-reclosing function automatically restores power after temporary faults, which is particularly valuable for overhead lines where transient faults are common. This feature significantly improves system availability by reducing the duration of outages. The relay’s event recording and oscillographic capabilities provide valuable data for post-event analysis, helping operators identify the root cause of trips and implement preventive measures.Typical ApplicationsIn utility distribution substations, the REF543KB127AAAA protects outgoing feeders supplying residential, commercial, or industrial loads. The relay provides overcurrent and earth-fault protection while supporting auto-reclosing to quickly restore service after transient faults on overhead lines.In industrial power distribution systems, the relay protects incoming feeders and distribution transformers. The thermal overload protection monitors transformer loading, while the comprehensive measurement functions provide data for energy management and power quality analysis.
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Full 12-month warranty on all components
Full 12-month warranty on all components
