ABB RED650, Руководство по применению

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ClockNumTransB
M12541-301 v2
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
M12541-307 v4
The elimination of zero sequence currents in the differential protection can be set
On / Off . In 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
M12541-310 v3
The possibility of cross-blocking can be set On / Off . The meaning of cross-blocking
is that the 2
nd
and 5
th
harmonic blocking in one phase also blocks the differential
function of the other phases. It is recommended to enable the cross-blocking if a
power transformer is included in the protection zone, otherwise not.
IMaxAddDelay
M12541-313 v4
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
M12541-316 v2
The possibility of delayed operation for small differential currents can be set On /
Off .
CurveType
M12541-321 v3
This is the setting of type of delay for low differential currents.
tMinInv
M12541-324 v4
This setting limits the shortest delay when inverse time delay is used. Operation
faster than the set value of
tMinInv is prevented.
If the user-programmable curve is chosen the characteristic of the curve is defined
by equation
13 .
Section 6
1MRK 505 393-UEN B
Differential protection
96 Line differential protection RED650 2.2 IEC
Application manual