GE Multilin D60 Line Distance Relay 5-1935 SETTINGS 5.6 CONTROL ELEMENTS5defines a minimum guaranteed duration of the POTT OP pulse. As this operand activates the trip table of the POTTscheme, the trip operands POTT TRIP A , B, C and 3P are sealed-in for the same period of time.ï GND DIR O/C FWD: This setting defines the FlexLogicô operand (if any) of a protection element that is used in addi-tion to the Zone 2 for identifying faults on the protected line, and thus, for keying the communication channel and initi-ating operation of the scheme. Good directional integrity is the key requirement for an over-reaching forward-lookingprotection element used as GND DIR O/C FWD. Even though any FlexLogicô operand could be used as GND DIR O/CFWD allowing the user to combine responses of various protection elements, or to apply extra conditions through Flex-Logicô equations, this extra signal is primarily meant to be the output operand from either the Negative-SequenceDirectional Overcurrent or Neutral Directional Overcurrent. Both of these elements have separate forward ( FWD ) andreverse ( REV ) output operands. The forward indication should be used (NEG SEQ DIR OC1 FWD or NEUTRAL DIR OC1FWD).ï POTT NO OF COMM BITS: This setting specifies the number of bits of the communications channel available for thescheme. The transmit codes and Trip Tables of the POTT scheme are the same as those for the permissive under-reaching transfer trip scheme. Please refer to the description of the PUTT scheme for more information.ï POTT RX1 through POTT RX4: These settings allow the user to select the FlexLogicô operands that represent thereceive signals for the scheme. Typically input contacts interfacing with a signaling system are used. In single-bit appli-cations, POTT RX1 must be used. In two-bit applications, POTT RX1 and POTT RX2 must be used. In four-bit applications,POTT RX1, POTT RX2, POTT RX3, and POTT RX4 must be used.Figure 5ñ114: POTT SCHEME LOGICSETTINGFLEXLOGIC OPERANDSSETTINGFLEXLOGIC OPERANDFLEXLOGIC OPERANDSETTINGSETTINGPOTT SCHEMEFUNCTION:Enabled = 1EnabledCustomPH DIST Z2 PKPGND DIR O/C FWD:LINE PICKUP LEO PKPOffPOTT OPPOTT PERMISSIVE ECHO:POTT ECHO COND:Disabled = 0Off = 0Disabled837014AD.CDRGND DIST Z2 PKPOff = 0SETTINGSSETTINGSSETTINGSSETTINGSSETTINGSPOTT RX PICKUPDELAY:TRANS BLOCK PICKUPDELAY:LINE END OPEN PICKUPDELAY:ECHO DURATION:TRANS BLOCK RESETDELAY:POTT SEAL-INDELAY:ANDORANDORANDANDANDANDANDOR0t RST0t RSTt PKPt PKPt PKP0ECHO LOCKOUT:Echo duration and lockout logicSETTINGSPOTT RX1:POTT RX2:POTT RX3:POTT RX4:POTT NO OF COMMBITS:Off = 0Off = 0Off = 0Off = 0ORFLEXLOGIC OPERANDSPOTT NO OF COMMBITS:POTT TX1POTT TX2POTT TX3POTT TX4ECHO TABLETRANSMIT TABLEPhaseSelectorRXRXRUNRUNFLEXLOGIC OPERANDSPOTT NO OF COMMBITS:POTT TRIP APOTT TRIP BPOTT TRIP CPOTT TRIP 3PTRIP TABLEPhaseSelectorRUNAND0100 msecFLEXLOGIC OPERANDSOPEN POLE OPAR FORCE 3P TRIPFLEXLOGIC OPERANDSOPEN POLE OPAR FORCE 3P TRIP
