ABB RELION 620 Series Technical Manual page 559

1MRS757644 F
620 series
Technical Manual
GUID-AF8C4517-178F-4421-8B88-675E30B2C1A1 V1 EN
Figure 280: Connection of the current transformers of Type 1. The connected
phase currents and the neutral current have opposite directions at an
external earth-fault situation. Both earthings are outside the area to
be protected.
GUID-124047A0-9B33-4D2F-9519-75D98C0A4534 V2 EN
Figure 281: Connection of the current transformers of Type 2. The phase currents
and the neutral current have equal directions at an external earth-
fault situation. Phase earthing is inside and neutral earthing is outside
the area to be protected.
Section 4
Protection functions
553