TheABB REB670 1MRK004822-BBis a premium Intelligent Electronic Device (IED) designed for high-speed, selectivebusbar differential protection. It offers exceptional flexibility for various wiring configurations, including double busbar and one-and-a-half circuit breaker arrangements.
Technical Specifications
Model Number:REB670 1MRK004822-BB.
Product Series:Relion 670.
Function:Busbar Differential Protection.
CT Inputs:Supports 4 to 24 inputs (Three-phase or Split-phase configurations).
Operating Speed:Typical 12 ms trip time for in-zone faults.
Wiring Support:Single/Double busbar, Bypass busbar, 1.5 Breaker, and Double Breaker.
Logic:Built-in dynamic zone automatic selection based on disconnector status.
Communication:Fully IEC 61850 compliant.
Key Features and Engineering Advantages
Dynamic Zone Selection:Features a built-in "image" of the busbar status. By monitoring disconnector positions, it dynamically assigns CTs to the correct protection zone, eliminating the need for complex external switching relays.
High Stability Against CT Saturation:Employs a unique measurement principle that remains stable even during severe CT saturation caused by heavy external faults, preventing nuisance trips.
Cost-Efficient CT Requirements:Unlike high-impedance schemes, the REB670 has lower requirements for the main CT and can share CT cores with other protection devices, reducing overall project costs.
Integrated CT Supervision:Continuously monitors the CT secondary circuits for open circuits. If a break is detected, the unit blocks the protection to prevent a false trip and triggers an alarm and waveform recording.
Selective Breaker Failure Tripping:Integrates breaker failure protection that works in tandem with the bus differential logic to isolate only the faulted section of the switchyard.
Simplified Circuitry:By handling zone selection and trip logic internally via software, it eliminates the need for extensive traditional hard-wiring for bus protection trip switching.
