CHAPTER 4: SETPOINTS FLEXLOGIC889 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL 4–381The characteristics of the logic gates are tabulated below, and the operators available inFlexLogic™ are listed in the FlexLogic™ operators table.Table 4-39: FlexLogic Gate CharacteristicsOne-shot POSITIVE ONE SHOT One shot that respondsto a positive going edge.A ‘one shot’ refers to asingle input gate thatgenerates a pulseresponse to an edge onthe input. The outputfrom a ‘one shot’ is True(positive) for only onepass through theFlexLogic equation. Thereis a maximum of 64 ‘oneshots’.NEGATIVE ONESHOTOne shot that respondsto a negative goingedge.DUAL ONE SHOT One shot that respondsto both the positive andnegative going edges.Logic gate NOT Logical NOT Operates on the previousparameter.OR(2)↓ OR(16) 2 input OR gate↓ 16input OR gateOperates on the 2previous parameters.↓Operates on the 16previous parameters.AND(2)↓ AND(16) 2 input AND gate↓ 16input AND gateOperates on the 2previous parameters.↓Operates on the 16previous parameters.NOR(2)↓ NOR(16) 2 input NOR gate↓ 16input NOR gate Operates on the 2previous parameters.↓Operates on the 16previous parameters.NAND(2)↓ NAND(16) 2 input NAND gate↓ 16input NAND gate Operates on the 2previous parameters.↓Operates on the 16previous parameters.XOR(2) 2 input Exclusive OR gate Operates on the 2previous parameters.LATCH (S,R) Latch (set, reset): reset-dominantThe parameter precedingLATCH(S,R) is the resetinput. The parameterpreceding the reset inputis the set input.Timer TIMER 1↓ TIMER 32 Timer set withFlexLogic™ timer 1settings. ↓ Timer set withFlexLogic™ timer 32settings.The timer is started bythe preceding parameter.The output of the timer isTIMER #.Assign virtual output = Virt Op 1↓ = VirtOp 32Assigns previousFlexLogic™ operand tovirtual output 1.↓ Assignsprevious FlexLogic™operand to virtual output96.The virtual output is setby the precedingparameterGATES NUMBER OF INPUTS OUTPUT IS ‘1’ (= ON) IF...NOT 1 input is ‘0’OR 2 to 16 any input is ‘1’AND 2 to 16 all inputs are ‘1’NOR 2 to 16 all inputs are ‘0’NAND 2 to 16 any input is ‘0’XOR 2 only one input is ‘1’TYPE SYNTAX DESCRIPTION NOTES
