Basler BE1-11g Instruction Manual page 18

6
BE1-11g protection systems enabled for IEC-61850 communication
(style Gxxxx5xxxxxxxx) have their frequency protection elements fixed
at four underfrequency elements, two overfrequency elements, and
two frequency rate-of-change elements.
Instantaneous Overcurrent (50) Protection
Directional overcurrent protection is provided by six instantaneous overcurrent elements. Digital signal
processing filters out unwanted harmonic components while providing fast overcurrent response with
limited transient overreach and overtravel.
Instantaneous overcurrent elements can be set for single-phase, three-phase, ground, neutral, positive-
sequence, negative-sequence, or unbalanced protection.
Breaker Failure (50BF) Protection
One breaker failure function provides protection and security for the power system against failure of the
monitored breaker.
Inverse Overcurrent (51) Protection
Seven inverse overcurrent elements can be set for single-phase, three-phase, ground, neutral, positive-
sequence, negative-sequence, or unbalanced protection. Inverse-overcurrent functions employ a dynamic
integrating timing algorithm covering a range from pickup to 40 times pickup with selectable
instantaneous or integrated reset characteristics. Inverse time overcurrent curves conform to IEEE Std
C37.112-1996 - IEEE Standard Inverse-Time Characteristic Equations for Overcurrent Relays, and
include seven curves similar to Westinghouse/ABB CO curves, five curves similar to GE IAC curves, four
table curves, a fixed time curve, and a user programmable curve.
Phase inverse overcurrent elements can be voltage restrained or controlled for generator backup
applications. Negative-sequence current protection (46) is included as a mode of the 51 (inverse
overcurrent) element. Each inverse overcurrent element can be set separately for forward, reverse, or
non-directional control.
A separate ground current input provides ground overcurrent protection for a separate ground CT.
Optionally, an SEF (sensitive earth fault) version of the separate ground CT is available.
Phase Current Differential (87) Protection (style GxxxxxxxPxxxxx or GxxxxxxxTxxxxx)
One phase current differential element provides three-phase, percentage-restrained, differential
protection with dual-slope, in-phase, differential mode. In flux balance mode, the differential CTs are
connected in a flux balancing configuration.
Neutral Current Differential (87N) Protection (style GxxxxxxxPxxxxx or GxxxxxxxTxxxxx)
One neutral current differential element provides sensitive phase-to-ground fault differential protection for
the wye winding of the transformer.
Power (32) Protection
Two directional power elements can be set for forward or reverse, overpower or underpower protection.
The element can be used for any application requiring directional power flow detection including intertie
protection (interconnects between an electric utility and a source of non-utility generation). The power
measurement algorithm is adapted as appropriate for any possible three-phase or single-phase voltage
transformer connection. Directional Power Protection can be set for one of three, two of three, three of
three, or total power.
Introduction
Note
9424200994 Rev U
BE1-11g