Directional Residual Current Protection Measuring 3I And Φ - ABB REC650 Technical Manual

1MRK 511 287-UEN A
6.5.7.4
Technical manual
The inverse time delay is defined as:
× × ×
kSN (3I 3U cos (reference))
0 0
=
t
inv
× × j
3I 3U cos (measured)
0 0
EQUATION1942 V2 EN
Directional residual current protection measuring 3I
The function will operate if the residual current is larger that the set value and the angle
φ = ang(3I )-ang(U = -3U
0 ref
IEC06000652 V3 EN
Figure 48: Example of characteristic
For trip, the residual current 3I
voltage 3U shall be larger than the set level UNREL> and the angle φ shall be in the
0
set sector ROADir and RCADir.
When the function is activated binary output signals START and STDIRIN are
activated. If the output signals are active after the set delay tDef the binary output
signals TRIP and TRDIRIN are activated.
The function indicate forward/reverse direction to the fault. Reverse direction is
defined as φ is within the angle sector: RCADir + 180° ± ROADir
This sub-function has definite time delay.
j
) is within the sector RCADir ± ROADir
0
RCADir = 0º
ROADir = 80º
Operate area
3I
0
IEC06000652-3-en.vsd
shall be larger than the set level INDir>, the release
0
Section 6
Current protection
(Equation 15)
and φ
0
-3U
0
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