Subaru impreza 2017, Owner'S Manual

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where:
IL1, IL2 and IL3 are fundamental frequency phasors of three individual phase currents.
The residual current is pre-processed by a discrete Fourier filter. Thus the phasor of
the fundamental frequency component of the residual current is derived. The
phasor magnitude is used within the EF4PTOC protection to compare it with the
set operation current value of the four steps (
IN1> , IN2> , IN3> or IN4> ).
If the residual current is larger than the set operation current and the step is used in
non-directional mode a signal from the comparator for this step is set to true. This
signal will, without delay, activate the output signal STINx (x=step 1-4) for this
step and a common START signal.
6.4.7.2 Internal polarizing
M13941-82 v11
A polarizing quantity is used within the protection in order to determine the
direction to the earth fault (forward/reverse).
The function can be set to use voltage polarizing, current polarizing or dual
polarizing.
Voltage polarizing
When voltage polarizing is selected, the protection will use the residual voltage
-3U
0
as the polarizing quantity U3P.
This voltage can be:
1. directly measured (when a dedicated VT input of the IED is connected in
PCM600 to the fourth analog input of the pre-processing block connected to
EF4PTOC function input U3P). This dedicated IED VT input shall be then
connected to the open delta winding of a three-phase main VT.
2. calculated from three-phase voltage input within the IED (when the fourth
analog input of the pre-processing block, connected to EF4PTOC analog
function input U3P, is NOT connected to a dedicated VT input of the IED in
PCM600). In such a case, the pre-processing block will calculate -3U
0
from
the first three inputs into the pre-processing block by using the following
formula:
UPol = -3U
0
= -(UL1 + UL2 + UL3)
EQUATION1875 V2 EN-US
(Equation 9)
where:
UL1, UL2 and UL3 are fundamental frequency phasors of three individual phase voltages.
In order to use this, all three phase-to-earth voltages must be connected to three IED VT
inputs.
Section 6
1MRK 505 384-UEN A
Current protection
114 Breaker protection REQ650 2.2 IEC
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