ABB RELION 650 Series Applications Manual page 166

Section 8
Current protection
IEC06000649 V3 EN-US
Figure 93: 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
The characteristic for this
IEC06000652 V3 EN-US
Figure 94: Characteristic for RCADir = 0° and ROADir = 80°
DirMode is set Forward or Reverse to set the direction of the operation for the directional
function selected by the
All the directional protection modes have a residual current release level setting
is set in % of
current to be detected.
160
U
ref
RCADir = −
3I
0
3 ⋅ I cos ϕ
0
ϕ = ang I (3 )
0
IEC06000649_3_en.vsd
INDir> and the residual current angle is within the sector RCADir ± ROADir .
OpMode when RCADir = 0° and ROADir = 80° is shown in figure 94.
RCADir = 0º
ROADir = 80º
OpMode .
IBase . This setting should be chosen smaller than or equal to the lowest fault
 
90 , ROADir = 90
− ang U ( )
ref
− 3U
0
Operate area
3I
0
-3U
0
IEC06000652-3-en.vsd
1MRK 505 363-UEN A
INRel> which
Application manual