ProcediaEnvironmentalSciences11(2011)1016–1022doi:10.1016/j.proenv.2011.12.155Availableonlineat(2011)000–000:lujor@163.comAbstractThewaterconsumptionoflargeusersinthewatersupplysystemisnecessaryintheperformanceofthemodelinganalyzeofwatersupplynetworkorwaterqualitychangingstudies.Thereisalackofreliable,low-costmethodthatisabletomodifytheusualmechanicalwatertoanintelligentone.Thisresearchmainlydescribesasimplydesignedtransformationfromgearrotationtoapracticableon/offpulsesignalwhichiscollectedandstoriedbyPLCastheterminal.AlldatecanbereadfromthePLCbyacomputerafterasamplingperiod,suchas10daysorless.Therunningresultsshowthattherecordingsystemisreliability,stability,whichprovidesapowerfuldatasupportforthemodelingofwatersupplynetworkandwaterconsumptionforecastoflargeusersindemonstrationarea.Thispaperdemonstratedsufficientmeasurementtransformationtechnology.Thebasicdesigncanalsobeadaptedforothertargetranges.Keywords:PLC;watersupplynetwork;largeusers;Watermeter1.IntroductionAsacoretechnologyofmodelingforurbanwatersupplynetwork,thewaterdailyconsumptionoflargeusersisparticularlyimportant.Amajorresearchinthispaperisontheuser'swaterconsumptionforeach15minutesofrecordingtimeinaccordancewithacycle7daystestdata,andobtainedthechangingcharacterfromittosupportthemodelingofwatersupplynetworkinthedemonstrationresearchingarea.Thereareabout30largewaterusersinthisregion,includingschools,officebuildings,hospitalsandfactory,etc.whosewatermetersarealmostbasicallytraditionalmechanicaltypemeters.Therefore,itisalmostimpossibletoachievethereal-timedatalogging.Currently,manynoveldesignsaboutmodifyingthemechanicalmetertoaelectronicorintelligentinstrumentarepresented,butmostofthemareusedforremotedataintegrateddatabasemanagementsystemsuchasintelligentbuildings,family,apartmentsorcommercialbuildingswhicharebasedonRIFsmartICcardorwirelesscommunicationtechnology[1-4],butthereislittleapplicationforthestudyofreal-timetesting.©2011PublishedbyElsevierLtd.Selectionand/orpeer-reviewunderresponsibilityoftheIntelligentInformationTechnologyApplicationResearchAssociation.OpenaccessunderCCBY-NC-NDlicense.1878-0296©2011PublishedbyElsevierLtd.Selectionand/orpeer-reviewunderresponsibilityoftheIntelligentInformationTechnologyApplicationResearchAssociation.OpenaccessunderCCBY-NC-NDlicense.1017Liujieetal./ProcediaEnvironmentalSciences11(2011)1016–1022Authorname/ProcediaEnvironmentalSciences00(2011)000–000BecauseProgrammableLogicController(PLC)cannotonlyimplementcomplexlogicoperations,butalsocompleteavarietyofsequenceortimingoftheclosed-loopcontrolfunctions,andalsoownadvantagessuchasasmallvolume,flexibleassembly,highanti-interferenceabilityandreliabilityinharshenvironments,longuninterruptedrunandsoon.Inthispaper,investigationshavebeencarriedouttorealizearealtimelargeuser’swaterconsumptionrecordsystem.2.TheStructureofRecordingSyetemThesystemconsistsofmeterrotorsensor,PLC,electricalswitches,powersupplybatteriesandwaterproofcasecomposition,asshowninFigure1.Aspecialelectronicsignalingmodulehasbeensettledonthecommonwatermeterrotorsensor.TheelectronicmodulecanturnmechanicalgearsignalsintopulsesignalwhichwouldbetransmittedtothePLCthroughsignalwire.Accordingtothepre-writtenprograms,thePLCrealizestheacquisitiontopulsesignals,dataprocessing,storage,andotherfunctions.Becausethesystemhasbeeninstalledinthewatermeterchamberwell,astablepowersupplyisnecessary.Two12V12AHaccumulatorsarebeusedinthisdesign.Basedontestingresults,thesystemcanrunatleast20daysundertheconditionsof10tem℃peratureenvironmentsand15minsamplingfrequency.Theexperimentsalsopresentedlowertemperaturecouldacceleratethepowerconsumption.Forinstant,twoaccumulatorshaverun12dayswhentheenvironmenttemperaturefallsto0.Inaword,℃twoaccumulatorscanguarantyatleastoneweekcontinuoussamplingoperationwithoutotherpowersupply.Moreover,acomputercanbeconnectedwiththePLCviaRS485convertingUSBmoduletoexporttheloggingdatetothecomputerafteracycleofdataacquisition,andthenusetheappropriatesoftwaretodealwiththedate.Asaresultofdutyandhumidinthewatermeterchamberwell,thePLCandaccumulatorareencapsulatedintoanIP68waterproofboxandsealthegapbyfluidsealantatlast.Figure1.Waterconsumptionrecordingsystemforlargeusersinthewells3.Sensor’sTransformation3.1TransformationTheory.Astheonlymeasurementinstrumentsforfinancialsettlementbetweenwatersupplyingcompanyandlargeusers,thewatermeterplaysanextremelyimportantpositioninwaterstatisticsforlargeusers.Currentlythewatermeteroflargeusersaremechanicalformsinsteadofremotemeterorintelligentones,whosediametersaremostlyDN50,DN100andDN150inJINANdemonstrationarea.Accordingtotheprojectplanning,thelargeusers’watermetershouldtobereadevery15minutesandlas