ABB RELION RET670, Applications Manual

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I1Base : Base current in primary Ampere for the HV-side of the transformer.
I2Base : Base current in primary Ampere for the LV-side of the transformer.
VBase : Base voltage in primary kV for the LV-side of the transformer.
MeasMode : Selection of single phase, or phase-phase, or positive sequence quantity to
be used for voltage and current measurement on the LV-side. The involved phases are
also selected. Thus, single phase as well as phase-phase or three-phase feeding on the
LV-side is possible but it is commonly selected for current and voltage.
Q1 , Q2 and Q3 : Mvar value of a capacitor bank or reactor that is connected between
the power transformer and the CT, such that the current of the capacitor bank (reactor)
needs to be compensated for in the calculation of circulating currents. There are three
independent settings
Q1 , Q2 and Q3 in order to make possible switching of three steps
in a capacitor bank in one bay.
TotalBlock : When this setting is Enabled the voltage control function, TR1ATCC (90)
for single control and TR8ATCC (90) for parallel control, is totally blocked for manual
as well as automatic control.
AutoBlock : When this setting is Enabled the voltage control function, TR1ATCC (90)
for single control and TR8ATCC (90) for parallel control, is blocked for automatic
control.
Operation
FSDMode : This setting enables/disables the fast step down function. Enabling can be
for automatic and manual control, or for only automatic control alternatively.
tFSD : Time delay to be used for the fast step down tapping.
Voltage
UseCmdUSet : This setting enabled makes it possible to set the target voltage level via
IEC 61850 set point command. This, in turn, makes the setting USet redundant.
VSet : Setting value for the target voltage, to be set in percent of VBase .
VDeadband : Setting value for one half of the outer deadband, to be set in percent of
VBase . The deadband is symmetrical around VSet , see section "Automatic voltage
control for a single transformer" , figure 363 . In that figure VDeadband is equal to
D
V.
The setting is normally selected to a value near the power transformer’s tap changer
voltage step (typically 75 - 125% of the tap changer step).
VDeadbandInner : Setting value for one half of the inner deadband, to be set in percent
of VBase . The inner deadband is symmetrical around VSet , see section "Automatic
voltage control for a single transformer" ,figure 363 . In that figure VDeadbandInner is
Section 15
1MRK 504 163-UUS A
Control
792 Transformer protection RET670 2.2 ANSI
Application manual