Description
ABB REB670 —— Intelligent Microcomputer Protection Unit
The REB670 intelligent microcomputer protection device is characterized by its flexibility of application. It is specially designed for the protection and monitoring of power system busbars, T-connected lines and branch lines, and has a wide range of applications from medium voltage to ultra-high voltage. Expandable input and output hardware modules enable the REB670 to meet the protection needs of single busbar, double busbar with or without side busbar, double circuit breaker and one and a half circuit breakers in a variety of wiring forms.
The REB670 is capable of selectively and reliably removing all types of phase grounds or earths within the protected area of a directly grounded or low-impedance grounded power system, while all types of multiphase faults within the protected area can be correctly acted upon in an ungrounded or high-impedance grounded power system.
The REB670 provides complete busbar protection. In addition to the differential protection function, the device has a built-in flexible dynamic zone automatic selection (corresponding to the position of the disconnecting switch). This enables the unit to realize dynamic connection of CTs to different busbar protection zones, as well as selective busbar protection and circuit breaker failure tripping and status monitoring of disconnectors and circuit breakers at the same time. Due to its unique measuring principle, the REB670 device requires less main CTs than other digital differential protection devices.