ABB RED615 Applications Manual page 78

Section 3
RED615 standard configurations
72
Non-directional (cross-country) earth-fault protection, using calculated Io,
EFHPTOC protects against double earth-fault situations in isolated or compensated
networks. This protection function uses the calculated residual current originating
from the phase currents.
GUID-169A80DA-A6A3-4BF5-9065-F78EFB23121C V1 EN
Figure 65: Cross-country earth-fault protection
The output BLK2H of three-phase inrush detector INRPHAR1 offers the possibility to
either block the function or multiply the active settings for any of the available
overcurrent function blocks.
GUID-6E272ED2-8A8D-47A0-9D96-095912F1894B V1 EN
Figure 66: Inrush detector function
Two negative-sequence overcurrent protection stages NSPTOC1 and NSPTOC2 are
provided for phase unbalance protection. These functions are used to protect the
feeder against phase unbalance.
NSPTOC1_OPERATE
NSPTOC2_OPERATE
GUID-1114A789-B912-4053-B00A-5DF48069E33F V1 EN
Figure 67: Negative-sequence overcurrent protection function
Phase discontinuity protection PDNSPTOC1 protects for interruptions in the normal
three-phase load supply, for example, in downed conductor situations.
GUID-109761C8-E52A-43F5-B3D2-95C402F79515 V1 EN
Figure 68: Phase discontinuity protection
EFHPTOC1
BLOCK OPERATE
ENA_MULT START
INRPHAR1
BLOCK BLK2H
NSPTOC1
BLOCK OPERATE
ENA_MULT START
NSPTOC2
BLOCK OPERATE
ENA_MULT START
OR
B1 O
B2
PDNSPTOC1
BLOCK OPERATE
START
1MRS758127 C
EFHPTOC1_OPERATE
EFHPTOC1_START
INRPHAR1_BLK2H
NSPTOC1_OPERATE
NSPTOC1_START
NSPTOC2_OPERATE
NSPTOC2_START
NSPTOC_OPERATE
PDNSPTOC1_OPERATE
PDNSPTOC1_START
RED615
Application Manual