ABB REB670 BUSBAR PROTECTION RELAY

Application
REB670 is designed for the selective, reliable and fast
differential protection of busbars, T-connections and meshed
corners. REB670 can be used for protection of single and
double busbar with or without transfer bus, double circuit
breaker or one-and-half circuit breaker stations. The IED is
applicable for the protection of medium voltage (MV), high
voltage (HV) and extra high voltage (EHV) installations at a
power system frequency of 50Hz or 60Hz. The IED can detect
all types of internal phase-to-phase and phase-to-earth faults in
solidly earthed or low impedance earthed power systems, as
well as all internal multi-phase faults in isolated or high-
impedance earthed power systems.
Ordering of VT inputs inside of the busbar protection IED will
allow integration of voltage related functionality like under-
voltage release, residual over-voltage, power functions,
metering and voltage recording during the faults. However
attention shall be given to the fact that inclusion of VT inputs will
reduce number of available CT inputs (in total 24 analogue
inputs are the product limit). Consequently when VT inputs are
ordered the busbar protection IED will be applicable for buses
with a fewer number of bays. Practically the number of available
CT inputs will limit the size of the station which can be
protected.