ABB Relion 670 Series Technical Reference Manual page 240

Section 6
Impedance protection
234
INDIR_A
AND
DFW_A
INDIR_AB
AND
DFW_AB
INDIR_CA
AND
DFW_CA
INDIR_B
AND
DFW_B
INDIR_AB
AND
INDIR_BC
AND
DFW_BC
INDIR_C
AND
DFW_C
INDIR_BC
AND
INDIR_CA
AND
ANSI05000201 V3 EN
Figure 113: Composition of phase selection signals for forward direction
Figure 114 presents the composition of output signals TRIP and PICKUP, where
internal signals NDIR_PP, FWD_PP and REV_PP are the equivalent to internal signals
NDIR_G, FWD_G and REV_G, but for the phase-to-phase loops.
AND
AND OR
OR
AND
OR
AND
OR
AND OR
AND
OR
AND
OR
1MRK505222-UUS C
FWD_IPH
15 ms 0
0 15 ms
FWD_A
0
15 ms
FWD_G
0
15 ms
FWD_B
0
15 ms
FWD_2PH
0
15 ms
15 ms
0
FWD_C
0
15 ms
FWD_3PH
0
15 ms
FWD_PP
0
15 ms
ANSI05000201-3-en.vsd
Technical reference manual