ABB RELION 650 Series Applications Manual page 95

1MRK 505 363-UEN A
ClockNumTransA
This is the phase shift from primary to secondary side for power transformer A. The phase
shift is given in intervals of 30 degrees, where 1 is -30 degrees, 2 is -60 degrees, and so on. The
parameter can be set within the range 0...11.
TraBOnInpCh
This parameter is used to indicate that a power transformer is included in the protection zone
at current terminal Y. This can be either a two-winding transformer or the second secondary
winding of a three-winding transformer. The current transformer feeding the IED is located at
the low voltage side of the transformer. The parameter is set within the range 0...3, where zero
is used if no transformer B is included in the protection zone.
The setting specifies the current input on the differential current function block where the
input current must be recalculated, that is, referred to the high voltage side, which is the
reference side of the differential protection. The set input measured current I will be
recalculated to I ×
determined by the product
RatVoltW1TraB
The rated voltage (kV) of the primary side (line side = high voltage side) of the power
transformer B.
RatVoltW2TraB
The rated voltage (kV) of the secondary side (non-line side = low voltage side) of the power
transformer B.
ClockNumTransB
This is the phase shift from primary to secondary side for power transformer B. The phase
shift is given in intervals of 30 degrees, where 1 is -30 degrees, 2 is -60 degrees and so on. The
parameter can be set within the range 0 – 11.
ZerSeqCurSubtr
The elimination of zero sequence currents in the differential protection can be set
case of a power transformer in the protected zone, where the zero sequence current cannot be
transformed through the transformer, that is, in the great majority of cases, the zero sequence
current must be eliminated.
ZerSeqCurSubtr must be set On if there is a transformer in the zone. The zero sequence
currents are then subtracted from all current terminals.
CrossBlockEn
The possibility of cross-blocking can be set
nd
2 and 5
phases. It is recommended to enable the cross-blocking if a power transformer is included in
the protection zone, otherwise not.
IMaxAddDelay
IMaxAddDelay is set as a multiple of IBase . The current level, under which a possible extra
added time delay (of the output trip command), can be applied. The possibility for delayed
operation for small differential currents is typically used for lines with a (minor) tapped
transformer somewhere in the protected circuit and where no protection terminal of the multi-
terminal differential protection is applied at the transformer site. If such a minor tap
transformer is equipped with a circuit breaker and its own local protection, then this
protection must operate before the line differential protection to achieve selectivity for faults
on the low voltage side of the transformer. To ensure selectivity, the current setting must be
higher than the greatest fault current for faults at the high voltage side of the transformer.
AddDelay
The possibility of delayed operation for small differential currents can be set
Application manual
RatVoltW2TraB / RatVoltW1TraB and shifted counterclockwise by the angle,
ClockNumTransB × 30 degrees.
th
harmonic blocking in one phase also blocks the differential function of the other
On / Off . The meaning of cross-blocking is that the
Section 6
Differential protection
M12541-285 v3
M12541-292 v5
M12541-295 v3
M12541-298 v3
M12541-301 v2
M12541-307 v4
On / Off . In
M12541-310 v3
M12541-313 v4
M12541-316 v2
On / Off .
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