Subaru impreza 2017, Owner'S Manual

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which will be then used, together with the phasor of the operating current, in order
to determine the direction to the earth fault (forward/reverse).
In order to enable current polarizing, the magnitude of the polarizing current shall
be bigger than a minimum level defined by setting parameter
IPolMin .
Dual polarizing
When dual polarizing is selected, the function will use the vectorial sum of the
voltage based and current based polarizing in accordance with the following
formula:
 
0 s
UTotPol=UPol UIPol=UPol Z IPol UPol RNPol jXNPol Ipol
      
IECEQUATION2408 V2 EN-US
(Equation 13)
UPol and IPol can be either zero sequence component or negative sequence
component depending upon the user selection.
Then the phasor of the total polarizing voltage UTotPol will be used, together with
the phasor of the operating current, to determine the direction of the earth fault
(forward/reverse).
6.4.7.3 External polarizing for earth-fault function
M13941-144 v6
The individual steps within the protection can be set as non-directional. When this
setting is selected, it is possible via the function binary input BLKSTx to provide
external directional control (that is, torque control) by, for example, using one of
the following functions if available in the IED:
1. Distance protection directional function.
2. Negative sequence polarized general current and voltage multi purpose
protection function.
6.4.7.4 Directional detection for earth fault function
GUID-FC382DD3-E2C8-455E-8CD5-1DE1793DD178 v6
Zero sequence components will be used for detecting directionality for the earth
fault function. In some cases, zero sequence quantities might detect directionality
incorrectly. In such a scenario, negative sequence quantities will be used. The user
can select either zero sequence components or negative sequence components for
detecting directionality with the parameter
SeqTypeIPol . I3PDIR input is always
connected to the same source as I3P input.
6.4.7.5 Base quantities within the protection
M13941-152 v6
The base quantities are entered as global settings for all functions in the IED. Base
current (
IBase ) shall be entered as rated phase current of the protected object in
primary amperes. Base voltage ( UBase ) shall be entered as rated phase-to-phase
voltage of the protected object in primary kV.
Section 6
1MRK 505 384-UEN A
Current protection
116 Breaker protection REQ650 2.2 IEC
Technical manual