ABB Relion 670 Series Technical Reference Manual page 805

1MRK505222-UUS C
13.2.2.5
13.2.2.6
Technical reference manual
Intertrip scheme
In the direct intertrip scheme, the carrier send signal CS is sent from an underreaching
zone that is tripping the line.
The received signal per phase is directly transferred to the trip function block for
tripping without local criteria. The signal is not further processed in the phase
segregated communication logic. In case of single-pole tripping the phase selection and
logic for tripping the three phases is performed in the trip function block.
Simplified logic diagram
The simplified logic diagram for one phase is shown in figure 393.
Section 13
Scheme communication
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