ABB Relion 670 Series Technical Reference Manual page 446

Section 7
Current protection
440
ANSI06000650 V2 EN
Figure 220: Characteristic with ROADir restriction
The function indicates forward/reverse direction to the fault. Reverse direction is
defined as 3I ·cos (φ + 180°) ≥ the set value.
0
It is also possible to tilt the characteristic to compensate for current transformer angle
error with a setting RCAComp as shown in the figure 221:
3I Operate area
0
-3V
3I cos
0
ROA
1MRK505222-UUS C
=-
=V RCA = 0°
V 3V
ref o
0 ref
ANSI06000650-2-
vsd
en06000650_ansi.vsd
Technical reference manual