ABB Relion 670 Series Technical Reference Manual page 215

1MRK505222-UUS C
Technical reference manual
NDIR_A
NDIR_B
NIDR_C
NDIR_AB
NDIR_BC
NDIR_CA
BLK
ANSI00000488 V2 EN
Figure 95: Composition of pickup signals in non-directional operating mode
Results of the directional measurement enter the logic circuits, when the zone operates
in directional (forward or reverse) mode, as shown in figure 96.
OR
AND
OR
AND
AND
OR
AND
OR
Section 6
Impedance protection
PU_A
PU_B
PU_C
PICKUP
en00000488-1_ansi.vsd
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