ABB Relion 670 Series Technical Reference Manual page 448

Section 7
Current protection
442
This variant has the possibility of choice between definite time delay and inverse time
delay.
The inverse time delay is defined as:
TDSN ( 3 I 3 V cos (
⋅ ⋅ ⋅
0 0
t
=
inv
3 I 3 V cos ( measured
⋅ ⋅ ϕ
0 0
EQUATION2032-ANSI 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(V ) is within the sector RCADir ± ROADir
0 ref
ANSI06000652 V2 EN
Figure 222: Example of characteristic
For trip, both the residual current 3I
the set levels INDirPU and VNRelPU and the angle φ shall be in the set sector ROADir
and RCADir.
Trip from this function can be blocked from the binary input BLKTRDIR.
When the function is activated binary output signals PICKUP and PUDIRIN are
activated. If the output signals are active after the set delay tDef the binary output
signals TRIP and TRDIRIN are activated.
reference ))
ϕ
)
RCA = 0º
ROA = 80º
Operate area
3I
0
ANSI06000652-2-en.vsd
and the release voltage 3V
0
1MRK505222-UUS C
and φ
0
V =-3V
ref 0
, shall be larger than
0
Technical reference manual
(Equation 91)