1.GeneralIntroduction1.1SummaryTheDDSF722ElectricSinglePhaseMulti-tariffEnergyMeterusedformeasuringthesinglephaseACpowerof50Hzbytimesharing(total,top,peak,flat,valleytariffpowerconsumption),itscapabilityaccordingtotheGB/T17215-1998 Class1and2StaticACEnergyMeter andGB/T15284-1994 Multi-tariff(timesharing)EnergyMeter ,thedatacommunicationruleaccordingtoDL/T645-1997 CommunicationRuleforMulti-functionEnergyMeter .MainFeature:DisplaybyLCDandcounter,long-live,highaccuracy,goodallergicperformance,lowpowerconsumption,smallvolume.Itadoptsspecialreal-timeclocktoguaranteethedependabilityofclockdata,adoptsinfraredrayor485communicationstoreadthemeterandsetthefunctions.1.2SpecificationsandMainTechniqueParameter1.2.1Specification TypeSpec.DDSF722AccuracyClass1.0,2.0RatedVoltage（V）120RatedCurrent（A）1.5(6)A2.5(10)A5(20)A10(40)A15(60)A20(80)AMeterConstant（imp/KWh）Asperthenameplate1.2.2BasicErrorLoadCurrent(A)PowerFactorCOS BasicError%Class1.0Class2.00.05Ib1.0 1.5 2.50.1Ib～Imax1.0 1.0 2.00.1Ib0.5(Log) 1.5 2.50.8(Leading) 1.5 0.2Ib～Imax0.5(Log) 1.0 2.0