ABB Relion REG670, Applications Manual

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9.14.3 Setting guidelines
9.14.3.1 Explanation of the setting parameters
Operation : Set to On in order to activate the function; set to Off to switch off the
complete function.
StartCurr : Operation phase current level given in % of IBase .
Characterist : Selection of time characteristic: Definite time delay and different types
of inverse time characteristics are available; see Technical Manual for details.
tDef_OC : Definite time delay. It is used if definite time characteristic is chosen; it
shall be set to 0 s if the inverse time characteristic is chosen and no additional delay
shall be added. Note that the value set is the time between activation of the start and
the trip outputs.
k : Time multiplier for inverse time delay.
tMin : Minimum operation time for all inverse time characteristics. At high currents
the inverse time characteristic might give a very short operation time. By setting this
parameter the operation time of the step can never be shorter than the setting.
Operation_UV : it sets On / Off the operation of the under-voltage stage.
StartVolt : Operation phase-to-phase voltage level given in % of UBase for the under-
voltage stage. Typical setting may be, for example, in the range from 70% to 80% of
the rated voltage of the generator.
tDef_UV : Definite time delay. Since it is related to a backup protection function, a
long time delay (for example 0.5 s or more) is typically used. Note that the value set
is the time between activation of the start and the trip outputs.
EnBlkLowV : This parameter enables the internal block of the undervoltage stage for
low voltage condition; the voltage level is defined by the parameter BlkLowVolt .
BlkLowVolt : Voltage level under which the internal blocking of the undervoltage
stage is activated; it is set in % of UBase . This setting must be lower than the setting
StartVolt . The setting can be very low, for example, lower than 10%.
VDepMode : Selection of the characteristic of the start level of the overcurrent stage as
a function of the phase-to-phase voltage; two options are available: Slope and Step.
See Technical Manual for details about the characteristics.
VDepFact : Slope mode : it is the start level of the overcurrent stage given in % of
StartCurr when the voltage is lower than 25% of UBase ; so it defines the first point of
the characteristic ( VDepFact * StartCurr /100* IBase ; 0.25* UBase ). Step mode : it is
the start level of the overcurrent stage given in % of StartCurr when the voltage is
lower than UHighLimit /100* UBase .
1MRK 502 071-UEN -
Section 9
Current protection
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062 397
Application manual