ABB REQ650 Applications Manual page 134

Section 6
Current protection
128
IEC06000648 V3 EN
Figure 63: Characteristic for RCADir equal to 0°
The characteristic is for RCADir equal to -90° is shown in figure 64.
U
ref
3 ⋅ I cos ϕ
0
IEC06000649 V3 EN
Figure 64: 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.
The characteristic for RCADir = 0° and ROADir = 80° is shown in figure 65.

RCADir = 0 , ROADir
3I
0
ϕ = ang(3I ) ang(3U − )
0 ref
− 3U
3I cos ⋅ ϕ
0
IEC06000648-3-en.vsd

RCADir = − 90 , ROADir = 90
3I
0
ϕ = ang I (3 ) − ang U ( )
0 ref
− 3U
0
IEC06000649_3_en.vsd
1MRK 505 291-UEN A

= 0
= U
0 ref

Application manual