CHAPTER 5: SETTINGS CONTROL ELEMENTSD60 LINE DISTANCE PROTECTION SYSTEM – INSTRUCTION MANUAL 5-3595Figure 5-206: CT failure detector logic5.8.13.6 Incipient fault detectorSETTINGS CONTROL ELEMENTS MONITORING ELEMENTS INCIPIENT FAULT 1Before a permanent cable fault occurs, there are usually signs of degrading insulation manifesting itself as a short, mostlyhalf-cycle spikes asserting at the phase voltage peak. Due to shortness of such spikes, they are not usually detected by theinstantaneous protection of the feeder, which operates on the RMS or fundamental component of the phase current with arelatively high pickup. INCIPIENT FAULT 1 INCIPIENT FAULT 1FUNCTION: DisabledRange: Disabled, Enabled INCIPNT FLT 1 BLOCK:OffRange: FlexLogic operand INCIPIENT FAULT 1SOURCE: SRC 1Range: SRC 1, SRC 2, SRC 3, SRC 4 INCIPIENT FAULT 1PICKUP: 0.50 puRange: 0.10 to 10.00 pu in steps of 0.01 INCIPNT FLT 1 MODE:Number of countsRange: Number of counts, Counts per window INCIPIENT FLT 1 TRIPCOUNTS NUMBER: 2Range: 1 to 10 in steps of 1 INCIPNT FLT 1 DETECTWINDOW: 10.00 sRange: 0.00 to 1000.00 s in steps of 0.01 INCIPIENT FAULT 1RESET DELAY: 0.100 sRange: 0.000 to 65.535 s in steps of 0.001 INCIPIENT FAULT 1TARGET: Self-resetRange: Self-reset, Latched, Disabled INCIPIENT FAULT 1EVENTS: DisabledRange: Disabled, Enabled
