ABB REC670 Applications Manual page 193

1MRK 511 401-UEN A
Bay control REC670 2.2 IEC
Application manual
With OpMode set to 3I0cosfi the current component in the direction equal to the
characteristic angleRCADir has the maximum sensitivity. The characteristic for
RCADir is equal to 0° is shown in Figure 81.
IEC06000648 V4 EN-US
Figure 81: Characteristic for RCADir equal to 0°
The characteristic is for RCADir equal to -90° is shown in Figure 82.
U
ref
3 ⋅ I cos ϕ
0
IEC06000649 V3 EN-US
Figure 82: Characteristic for RCADir equal to -90°
When OpMode is set to 3U03I0cosfi the apparent residual power component in the
direction is measured.
When OpMode is set to 3I0 and fi the function will operate if the residual current is
larger than the setting INDir> and the residual current angle is within the sector
RCADir ± ROADir.
o
=
RCADir 0 , ROADir
3I
0
j = -
ang(3I ) ang(3U )
0 ref
-
3U
× j
3I cos
0
IEC06000648-4-en.vsd

RCADir = − 90 , ROADir = 90
3I
0
ϕ = ang I (3 ) − ang U ( )
0 ref
− 3U
0
IEC06000649_3_en.vsd
Section 8
Current protection
o
=
90
=
U
0 ref

187