ABB REG650 ANSI, Technical Manual

Page: 216 / 728

The inverse time delay is defined as:
0 0
inv
0 0
kSN (3I 3U cos (reference))
t
3I 3U cos (measured)
× × × j
=
× × j
EQUATION1942 V2 EN
(Equation 55)
8.3.7.4 Directional residual current protection measuring 3I
0
and φ
The function will operate if the residual current is larger that the set value and the angle
φ = ang(3I
0
)-ang(U
ref
= -3U
0
) is within the sector RCADir ± ROADir
-3U
0
Operate area
3I
0
RCADir = 0º
ROADir = 80º
IEC06000652-3-en.vsd
IEC06000652 V3 EN
Figure 104: Example of characteristic
For trip, the residual current 3I
0
shall be larger than the set level INDir> , the release
voltage 3U
0
shall be larger than the set level UNREL> and the angle φ shall be in the
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.
Section 8
1MRK 502 048-UEN A
Current protection
210
Technical manual