GE D60 Instruction Manual page 573

CHAPTER 5: SETTINGS
5.8.13.6 Incipient fault detector
SETTINGS  CONTROL ELEMENTS  MONITORING ELEMENTS  INCIPIENT FAULT 1
 INCIPIENT FAULT 1

Before a permanent cable fault occurs, there are usually signs of degrading insulation manifesting itself as a short, mostly
half-cycle spikes asserting at the phase voltage peak. Due to shortness of such spikes, they are not usually detected by the
instantaneous protection of the feeder, which operates on the RMS or fundamental component of the phase current with a
relatively high pickup.
D60 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL
Figure 5-206: CT failure detector logic
INCIPIENT FAULT 1

FUNCTION: Disabled
INCIPNT FLT 1 BLOCK:

Off
INCIPIENT FAULT 1

SOURCE: SRC 1
INCIPIENT FAULT 1

PICKUP: 0.50 pu
INCIPNT FLT 1 MODE:

Number of counts
INCIPIENT FLT 1 TRIP

COUNTS NUMBER: 2
INCIPNT FLT 1 DETECT

WINDOW: 10.00 s
INCIPIENT FAULT 1

RESET DELAY: 0.100 s
INCIPIENT FAULT 1

TARGET: Self-reset
INCIPIENT FAULT 1

EVENTS: Disabled
Range: Disabled, Enabled
Range: FlexLogic operand
Range: SRC 1, SRC 2, SRC 3, SRC 4
Range: 0.10 to 10.00 pu in steps of 0.01
Range: Number of counts, Counts per window
Range: 1 to 10 in steps of 1
Range: 0.00 to 1000.00 s in steps of 0.01
Range: 0.000 to 65.535 s in steps of 0.001
Range: Self-reset, Latched, Disabled
Range: Disabled, Enabled
CONTROL ELEMENTS
5
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