ABB Relion REC670 - Page 145

= =
o o
0 , 90RCADir ROADir
0
3I
j = -
0 ref
ang(3I ) ang(3U )
- =
0 ref
3U U
0
3I cos× j
IEC06000648-4-en.vsd
IEC06000648 V4 EN-US
Figure 65: Characteristic for RCADir equal to 0°
The characteristic is for RCADir equal to -90° is shown in Figure 66.
IEC06000649_3_en.vsd
ref
U
= − =
 
90 , 90RCADir ROADir
0
3I
0
3 ⋅ ϕI cos
ϕ = −
0
(3 ) ( )
ref
ang I ang U
−
0
3U
IEC06000649 V3 EN-US
Figure 66: 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 this
OpMode when RCADir = 0° and ROADir = 80° is shown in figure 67.
1MRK 511 358-UEN A Section 7
Current protection
139
Application manual