CHAPTER 5: SETTINGS GROUPED ELEMENTSG30 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL 5-2015The positive-sequence restraint must be considered when testing for pickup accuracy and response time (multiple ofpickup). The operating quantity depends on how test currents are injected into the relay (single-phase injection):Eq. 5-40NEUTRAL IOC1 FUNCTION — This setting enables and disables the neutral instantaneous overcurrent protection element.NEUTRAL IOC1 SIGNAL SOURCE — This setting selects the signal source for the neutral instantaneous overcurrent protectionelement.NEUTRAL IOC1 PICKUP — This setting specifies the neutral instantaneous overcurrent pickup level in per-unit values.NEUTRAL IOC1 PICKUP DELAY — This setting delays the assertion of the NEUTRAL IOC OP operands. It is used to achieve timingcoordination with other elements and relays.NEUTRAL IOC1 RESET DELAY — This setting specifies a delay for the reset of the neutral instantaneous overcurrent elementbetween the operate output state and the return to logic 0 after the input passes outside the defined pickup range. Thissetting is used to ensure that the relay output contacts are closed long enough to ensure reception by downstreamequipment.NEUTRAL IOC1 BLOCK — Assertion of the operand assigned to this setting blocks operation of the neutral instantaneousovercurrent element.NEUTRAL IOC1 EVENTS — This setting enables and disables the logging of neutral instantaneous overcurrent events in thesequence of events recorder.Figure 5-101: Neutral IOC1 logic5.7.5.4 Neutral directional overcurrent (ANSI 67N, IEC PDEF/PTOC)SETTINGS GROUPED ELEMENTS SETTING GROUP 1(6) NEUTRAL CURRENT NEUTRAL DIRECTIONALOC1(2) NEUTRAL DIRECTIONAL OC1 NEUTRAL DIR OC1FUNCTION: DisabledRange: Disabled, Enabled NEUTRAL DIR OC1SOURCE: SRC 1Range: SRC 1, SRC 2, SRC 3, SRC 4 NEUTRAL DIR OC1POLARIZING: VoltageRange: Voltage, Current, Dual, Dual-V, Dual-I NEUTRAL DIR OC1 POLVOLT: Calculated V0Range: Calculated V0, Measured VX NEUTRAL DIR OC1 OPCURR: Calculated 3I0Range: Calculated 3I0, Measured IG NEUTRAL DIR OC1 POS-SEQ RESTRAINT: 0.063Range: 0.000 to 0.500 in steps of 0.001
