5-14 D30 Line Distance Protection System GE Multilin5.2 PRODUCT SETUP 5 SETTINGS5We have:CT primary = “100 A”, andVT primary = PHASE VT SECONDARY x PHASE VT RATIO = 66.4 V x 208 = 13811.2 VThe power cut-off is therefore:power cut-off = (CURRENT CUT-OFF LEVEL VOLTAGE CUT-OFF LEVEL CT primary VT primary)/VT secondary= ( 0.02 pu 1.0 V 100 A 13811.2 V) / 66.4 V= 720.5 wattsAny calculated power value below this cut-off will not be displayed.Lower the VOLTAGE CUT-OFF LEVEL and CURRENT CUT-OFF LEVEL with care as the relay accepts lower signalsas valid measurements. Unless dictated otherwise by a specific application, the default settings of “0.02pu” for CURRENT CUT-OFF LEVEL and “1.0 V” for VOLTAGE CUT-OFF LEVEL are recommended.5.2.3 CLEAR RELAY RECORDSPATH: SETTINGS PRODUCT SETUP CLEAR RELAY RECORDSSelected records can be cleared from user-programmable conditions with FlexLogic™ operands. Assigning user-program-mable pushbuttons to clear specific records are typical applications for these commands. Since the D30 responds to risingedges of the configured FlexLogic™ operands, they must be asserted for at least 50 ms to take effect.Clearing records with user-programmable operands is not protected by the command password. However, user-program-mable pushbuttons are protected by the command password. Thus, if they are used to clear records, the user-programma-ble pushbuttons can provide extra security if required.For example, to assign user-programmable pushbutton 1 to clear demand records, the following settings should be applied.1. Assign the clear demand function to pushbutton 1 by making the following change in the SETTINGS PRODUCT SETUP CLEAR RELAY RECORDS menu:CLEAR DEMAND: “ PUSHBUTTON 1 ON ”2. Set the properties for user-programmable pushbutton 1 by making the following changes in the SETTINGS PRODUCTSETUP USER-PROGRAMMABLE PUSHBUTTONS USER PUSHBUTTON 1 menu:PUSHBUTTON 1 FUNCTION: “Self-reset”PUSHBTN 1 DROP-OUT TIME: “0.20 s” CLEAR RELAY RECORDSCLEAR FAULT REPORTS:OffRange: FlexLogic™ operandMESSAGE CLEAR EVENT RECORDS:OffRange: FlexLogic™ operandMESSAGE CLEAR OSCILLOGRAPHY?NoRange: FlexLogic™ operandMESSAGE CLEAR ARC AMPS 1:OffRange: FlexLogic™ operandMESSAGE CLEAR ARC AMPS 2:OffRange: FlexLogic™ operandMESSAGE RESET UNAUTH ACCESS:OffRange: FlexLogic™ operandMESSAGE CLEAR DIR I/O STATS:OffRange: FlexLogic™ operand.Valid only for units with Direct I/O module.3NOTE
