GE D60 Instruction Manual page 723

CHAPTER 9: THEORY OF OPERATION
Operand Description
PHASE SELECT CG Asserted when a phase C to ground fault is detected
PHASE SELECT AB Asserted when a phase A to B fault is detected
PHASE SELECT BC Asserted when a phase B to C fault is detected
PHASE SELECT CA Asserted when a phase C to A fault is detected
PHASE SELECT ABG Asserted when a phase A to B to ground fault is detected
PHASE SELECT BCG Asserted when a phase B to C to ground fault is detected
PHASE SELECT CAG Asserted when a phase C to A to ground fault is detected
If none of the fault types outlined in the table is determined, then three-phase fault conditions are checked to detect the
presence of positive-sequence current and the absence of both zero-sequence and negative-sequence current. If these
conditions are met, then the
PHASE SELECT 3P
asserted, indicating that the phase selector failed to identify the fault type.
Finally, the states of the following additional FlexLogic operands are determined.
Table 9-13: FlexLogic operands asserted
Operand Description
PHASE SELECT SLG Asserted if any of
PHASE SELECT MULTI-P Asserted if neither the
The phase selector operands are reset a half cycle after the
defined by the
PHASE SELECTOR RESET
operated.
D60 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
FlexLogic operand is asserted; otherwise, the
PHASE SELECT AG, PHASE SELECT
nor
PHASE SELECT SLG PHASE SELECT VOID
OPEN POLE OP
setting (in the Trip Output element) once the disturbance detector (50DD) initially
Figure 9-11: Phase selector logic
PHASE SELECT VOID
BG, or operands is active
PHASE SELECT CG
operands are being asserted
FlexLogic operand is asserted or after delay
SINGLE-POLE TRIPPING
operand is
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