ABB ret650, Applications Manual

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I3PW2CT2: Phase currents for winding 2 second current transformer set for multi-
breaker arrangements. Used when protecting an autotransformer. When not
required, configure input to "GRP-OFF".
Recommendation for Binary input signals
M13052-17 v8
Refer to the pre-configured configurations for details.
BLOCK: The input will block the operation of the function. It can be used, for
example, to block the operation during special service conditions for a limited time.
Recommendation for output signals
M13052-21 v9
Refer to pre-configured configurations for details.
START: The start output indicates that Idiff is in the operate region of the
characteristic.
TRIP: The trip output is activated when all operating criteria are fulfilled.
DIROK: The output is activated when the directional criteria has been fulfilled.
BLK2H: The output is activated when the function is blocked due to high level of
second harmonic.
6.2.3.2 Settings
M13052-28 v13
The parameters for the restricted earth fault protection, low impedance function
REFPDIF are set via the local HMI or PCM600.
Common base IED values for primary current ( IBase ), primary voltage ( UBase )
and primary power ( SBase ) are set in a Global base values for settings function
GBASVAL.
GlobalBaseSel : It is used to select a GBASVAL function for reference of base
values.
Operation : The operation of REFPDIF can be switched On / Off .
IdMin : The setting gives the minimum operation value. The setting is in percent of
the IBase value of the chosen GlobalBaseSel . For function operation, the neutral
current must be larger than half of this value. A recommended setting is 30% of
power transformer-winding rated current for a solidly earthed winding.
ROA : Relay operate angle for zero sequence directional feature. It is used to
differentiate an internal fault and an external fault based on measured zero
sequence current and neutral current.
CTFactorPri1 : A factor to allow a sensitive function also at multi-breaker
arrangement where the rating in the bay is much higher than the rated current of the
transformer winding. The stabilizing can then be high so an unnecessary high fault
level can be required. The setting is normally 1.0 but in multi-breaker arrangement
the setting shall be CT primary rating/
IBase .
1MRK 504 169-UEN A
Section 6
Differential protection
Transformer protection RET650 2.2 IEC 99
Application manual