GE L60 Instruction Manual

Also see for L60: Communications manual Communications guide Instruction manual Instruction manual Instruction manual

Contents

5-314 L60 LINE PHASE COMPARISON SYSTEM – INSTRUCTION MANUALCONTROL ELEMENTS CHAPTER 5: SETTINGS5The open pole detector is intended to identify an open pole of the line circuit breaker. The scheme monitors the breakersauxiliary contacts, current in the circuit, and optionally voltage on the line. The scheme generates output operands used toblock the phase selector and some specific protection elements, thus preventing maloperation during the dead time of asingle-pole autoreclose cycle or any other open pole conditions.The scheme declares an open pole at the moment a single-pole trip is issued.In two-breaker and breaker-and-a-half applications, an open pole condition is declared when one or more of the followinghold:• Both breakers have an open pole on the same phase• The current on the line drops below a threshold• The current and voltage on the line drop below a thresholdThe open pole feature uses signals defined by the GROUPED ELEMENTS  SETTING GROUP 1(6)  DISTANCE  DISTANCESOURCE setting. Voltage supervision can be used only with wye VTs on the line side of the breaker.OPEN POLE CURRENT PICKUP — This setting establishes the current threshold below which an open pole is declared.OPEN POLE LINE XC1 — Specifies positive-sequence reactance of the entire line. If shunt reactors are applied, this value is anet capacitive reactance of the line and the reactors installed between the line breakers. The value is entered in secondaryohms. This setting is relevant if open pole condition at the remote end of the line is to be sensed and utilized by the relay.OPEN POLE LINE XC0 — Specifies zero-sequence reactance of the entire line. If shunt reactors are applied, this value is a netcapacitive reactance of the line and the reactors installed between the line breakers. Do not enter the value in secondaryohms. This setting is relevant if open pole condition at the remote end of the line is to be sensed and utilized by the relay(OPEN POLE REM OP FlexLogic operand).OPEN POLE REM CURR PKP — Specifies pickup level for the remote-end current estimated by the relay as the local currentcompensated by the calculated charging current. The latter is calculated based on the local voltages and the capacitivereactances of the line. This setting is relevant if open pole condition at the remote end of the line is to be sensed andutilized by the relay (OPEN POLE REM OP FlexLogic operand).OPEN POLE MODE — Selects the mode of operation of the open pole function. When the “Accelerated” mode is chosen, anopen pole is declared ½ cycle after trip output operation and before the breaker pole opens. This blocks distance loopsinvolved in the faulted phase and phase selector, and arms the trip output to produce three-pole trip for the next fault. Ifthe fault evolves into multi-phase fault before breaker pole opens for the first fault, the remaining in-service distance loopsinitiates a three-pole trip. When the “Traditional” mode is selected, then an open pole is declared only after the breakeropens and current disappears. If the fault evolves into a multi-phase fault before the circuit breaker pole opens for the firstfault, the phase selector changes the fault type from a single-line-to-ground fault to a multi-phase fault, thereby initiatinga three-pole trip.OPEN POLE DETECTION — Selects the signals used to detect an open pole condition. When “I AND V AND CBaux” value isselected, the breaker 52 contacts and the current with optional voltage signals are used to determine open poleconditions. For the “I AND V only” selection, only the current with optional voltage signals are used.For convenience, the position of the breaker poles defined in the breaker control feature and available as FlexLogicoperand BREAKER 1ΦA CLSD through BREAKER 1 ΦC CLSD and BREAKER 1 OOS are used by the open pole feature if the “I AND VAND CBaux” detection value is selected.For correct operation of the open pole detector, the breaker control, trip output, and single-pole autoreclose features mustbe enabled and configured properly. When used in configuration with only one breaker, set the BREAKER 2 FUNCTION to“Enabled” and the BREAKER 2 OUT OF SV setting to “On” (see the Breaker Control section earlier in this chapter for details). OPEN POLE DETECTION:I AND V AND CBauxRange: I AND V AND CBaux, I AND V only OPEN POLE TARGET:Self-ResetRange: Self-Reset, Latched, Disabled OPEN POLE EVENTS:DisabledRange: Enabled, Disabled