Setting Guidelines - ABB REC670 Applications Manual

1MRK 511 401-UUS A
17.8.3
Bay control REC670 2.2 ANSI
Application manual
distance to fault is very important for those involved in operation and maintenance.
Reliable information on the fault location greatly decreases the downtime of the
protected lines and increases the total availability of a power system.
The fault locator is started with the input CALCDIST to which trip signals indicating
in-line faults are connected, typically distance protection zone 1 and accelerating zone
or the line differential protection. The disturbance report must also be started for the
same faults since the function uses pre- and post-fault information from the trip value
recorder function (TVR).
Beside this information the function must be informed about faulted phases for correct
loop selection (phase selective outputs from differential protection, distance protection,
directional OC protection, and so on). The following loops are used for different types
of faults:
• for 3 phase faults: loop A-B.
• for 2 phase faults: the loop between the faulted phases.
• for 2 phase-to-ground faults: the loop between the faulted phases.
• for phase-to-ground faults: the phase-to-ground loop.
LMBRFLO function indicates the distance to fault as a percentage of the line length, in
kilometers or miles as selected on the local HMI. LineLengthUnit setting is used to
select the unit of length either, in kilometer or miles for the distance to fault. The
distance to the fault, which is calculated with a high accuracy, is stored together with
the recorded disturbances. This information can be read on the local HMI, uploaded to
PCM600 and is available on the station bus according to IEC 61850–8–1.
The distance to fault can be recalculated on the local HMI by using the measuring
algorithm for different fault loops or for changed system parameters.

Setting guidelines

The parameters for the Fault locator function are set via the local HMI or PCM600.
The Fault locator algorithm uses phase voltages, phase currents and residual current in
observed bay (protected line) and residual current from a parallel bay (line, which is
mutual coupled to protected line).
The Fault locator has close connection to the Disturbance report function. All external
analog inputs (channel 1-30), connected to the Disturbance report function, are
available to the Fault locator and the function uses information calculated by the Trip
value recorder. After allocation of analog inputs to the Disturbance report function, the
user has to point out which analog inputs to be used by the Fault locator. According to
the default settings the first four analog inputs are currents and next three are voltages
Section 17
Monitoring
IP14835-1 v1
M13769-3 v6
541