1、超聲波的概念與書語及超聲波流量計(jì)測(cè)量的原理PT878液體超聲波流量計(jì)的組成PT878液體超聲波流量計(jì)安裝考慮因素PT878液體超聲波流量計(jì)的故障判斷PT878液體超聲波流量計(jì)的操作超聲波的概念與書語及超聲波流量計(jì)測(cè)量的原理超聲波的概念與書語頻率:次聲波 0 to 20 Hz聲波 20 Hz to 20 kHz (Human hearing)超聲波 20 kHz超聲波的概念超聲波的概念與書語超聲波的概念傳感器工作原理 傳感器電能 機(jī)械能機(jī)械能 電能壓電晶體的變化每個(gè)傳感器能發(fā)射和接受發(fā)射接收傳感器工作原理 傳感器發(fā)射接收超聲波流量計(jì)原理：時(shí)差法 傳感器既發(fā)送信號(hào)又接收 信號(hào)V tup = 超聲波

2、被流體減速 tdn = 超聲波被流體加速tuptdnttupdn tttupdn=-DtPc-Vsinup=qtPc+Vsindn=qVLP 聲信號(hào)傳播時(shí)間逆流傳播, tup順流傳播, tdn超聲波流量計(jì)原理：時(shí)差法 傳感器既發(fā)送信號(hào)又接收V tup VLP聲速 c = Ptavg, ttt2avg = dnup+Q=Velocity AreaQ=V A體積流量tt tttupdnupdn=-DtPc-VsintPc+Vsinupdn=qq流速 V C2L2 t超聲波流量計(jì)原理：時(shí)差法VLP聲速 c = Ptavg, ttt2avg 夾裝式傳感器 折射原理 Snells Lawc1=傳感器內(nèi)傳

3、播速度c2=管壁的傳播速度c3=流體內(nèi)的傳播速度S=傳感器的間距c11c223c3LSW.T.Classic “clamp-on” approach夾裝式傳感器 c1=傳感器內(nèi)傳播速度c11c2PT878液體超聲波流量計(jì)的組成1主機(jī)傳感器信號(hào)線充電器紅外線轉(zhuǎn)RS232測(cè)厚探頭偶合劑儀器包PT878液體超聲波流量計(jì)的組成1主機(jī)PT878液體超聲波流量計(jì)的組成21.OKS傳感器夾具2.CRS和CPT傳感器夾具3.CF-LP傳感器夾具PT878液體超聲波流量計(jì)的組成21.OKS傳感器夾具所配傳感器的特性及用途傳感器代碼型號(hào)C-RS402C-RS401C-PT116CF-LP 23OKSSpecial

4、(91)形狀頻率1.0 MHz0.5 MHz1.0 MHz4.0 MHz2.0 MHz發(fā)射角度42423559.5傳播時(shí)間17.320.327.55.85傳播速度248424842674.63328使用溫度-40 to 150 C-40 to 150 C-20 to 210C-40 to 230C-200 to 360 C所配傳感器的特性及用途傳感器代碼C-RSC-RSC-PTCF傳感器選用原則1.溫度要求.2.信號(hào)要求.導(dǎo)聲較差的介質(zhì)和大的管道選擇低頻探頭.3.精度要求.頻率越高精度越高.2寸以下一般用CF-LP探頭.傳感器選用原則1.溫度要求.管道要求1.直管段要求:前10后5.即在傳感器

5、安裝位置前10倍直徑長(zhǎng)度和后5倍的直徑長(zhǎng)度無彎頭,閥門等引起流體擾動(dòng)的裝置.2.準(zhǔn)確測(cè)量管經(jīng)外徑周長(zhǎng)或直徑.3.確定管道材質(zhì)和壁厚及接觸溫度.4.確定是否有內(nèi)襯及種類和厚度.管道要求1.直管段要求:前10后5.即在傳感器安裝位置前10介質(zhì)要求1.已列出的介質(zhì)直接選擇2.未列出的介質(zhì)需輸入聲速或選擇跟蹤窗口測(cè)試3.確定聲速的目的是在窗口中央將信號(hào)檢出.END OF TRANSMITGOOD SNRWINDOW介質(zhì)要求1.已列出的介質(zhì)直接選擇END OF TRANSMI安裝方式1.根據(jù)管道大小和信號(hào)強(qiáng)度選擇安裝方式A.單聲程:大管道和復(fù)雜應(yīng)用B:雙聲程:首選方式,安裝簡(jiǎn)單.C:多聲程:小管道,信號(hào)

6、特強(qiáng).安裝位置:水平管道 3點(diǎn)和9點(diǎn)位置 垂直管道必須是介質(zhì)向上流安裝方式1.根據(jù)管道大小和信號(hào)強(qiáng)度選擇安裝方式校準(zhǔn)1.標(biāo)定后輸入校驗(yàn)系數(shù)2.雷諾數(shù)修正.Re= 雷諾數(shù) #V=流體流速ID=內(nèi)徑=運(yùn)動(dòng)粘度(ft2/sec or m2/sec)校準(zhǔn)1.標(biāo)定后輸入校驗(yàn)系數(shù)進(jìn)行信號(hào)診斷介質(zhì)充滿管道后需檢測(cè)的參數(shù)和信號(hào)流向是否正常信號(hào)強(qiáng)度SSup;SSdn 聲速SNSP波型等根據(jù)診斷參數(shù)調(diào)整有關(guān)輸入?yún)?shù)得到準(zhǔn)確結(jié)果進(jìn)行信號(hào)診斷介質(zhì)充滿管道后需檢測(cè)的參數(shù)和信號(hào)進(jìn)行信號(hào)診斷信號(hào)強(qiáng)度SSup;SSdn 50-55偏低可能不穩(wěn)定55-60 低一點(diǎn),可以接受60-65 好65-75 非常好75-99 信號(hào)飽和,

7、分辨率可能降低0.電纜線開路100.控制器故障聲速SNSP應(yīng)在合理范圍內(nèi).如水1500m/s左右 進(jìn)行信號(hào)診斷信號(hào)強(qiáng)度SSup;SSdn 進(jìn)行信號(hào)診斷錯(cuò)誤代碼E0: 無錯(cuò)誤E1: 信號(hào)太低E2:聲速錯(cuò)誤E3: 流速超出范圍E4: 信號(hào)質(zhì)量太差E5:流速變化太大 進(jìn)行信號(hào)診斷錯(cuò)誤代碼FeaturesLarge, Backlit LCDSimplified KeypadGraphical User Interface (GUI)Faster Update RateImproved Peak DetectionLarger, more powerful Data LoggerXML-format S

8、ite FilesFlash memory Simple UpgradesPT878 Ultrasonic FlowmeterIrDA - compatible wireless data transferUp to 11 hours run time per chargeFeaturesPT878 Ultrasonic FlowmLCD Display240 x 200 resolutionRoom for 1 to 4 measurementsLarge signal waveform displaysWhite EL BacklightPT878 Ultrasonic Flowmeter

9、LCD DisplayPT878 Ultrasonic FlLCD Display240 x 200 resolutionRoom for 1 to 4 measurementsLarge signal waveform displaysWhite EL BacklightPT878 Ultrasonic FlowmeterLCD DisplayPT878 Ultrasonic FlKeypadRubberized keysClick actionSimple universal layoutSoft Function KeysPT878 Ultrasonic FlowmeterKeypadP

10、T878 Ultrasonic FlowmetGraphical UserInterface (GUI)Keeps related information togetherAll choices visible at the same timePT878 Ultrasonic FlowmeterGraphical UserPT878 UltrasonicGUI ControlsMenusRelated items grouped togetherUse to move through choicesUse to change menusPress Enter to selectPT878 Ul

11、trasonic FlowmeterGUI ControlsPT878 Ultrasonic FGUI ControlsTabsQuick access to related formsUse to select formPress Enter to open the formPT878 Ultrasonic FlowmeterGUI ControlsPT878 Ultrasonic FGUI ControlsButtonsSelects between mutually exclusive choicesUse to select buttonPress Enter to activateP

12、T878 Ultrasonic FlowmeterGUI ControlsPT878 Ultrasonic FPT878 Ultrasonic FlowmeterGUI ControlsListsChoose from all applicable settingsUse to move one itemUse to scroll the listPT878 Ultrasonic FlowmeterGUI PT878 Ultrasonic FlowmeterGUI ControlsNumeric EntryPress Enter to begin entering digitsPress to

13、 erase a digitPress Esc to cancel and restore original valuePress Enter to accept the new valueValues can be entered or displayed in either Metric or English units without having to change meter defaultsPT878 Ultrasonic FlowmeterGUI PT878 Ultrasonic FlowmeterGUI ControlsCheck BoxesUsed to turn an op

14、tion:On Off Press Enter to togglePT878 Ultrasonic FlowmeterGUI GUI ControlsFunction KeysChange according to form or menu activePress F1, F2, or F3 to selectPT878 Ultrasonic FlowmeterGUI ControlsPT878 Ultrasonic FGUI ControlsLocale-SpecificChange date, time, and decimal formats for local custom:MM/DD

15、/YYYYDD-MM-YYYYYYYY-MM-DD11:59 PM23:59123.45123,45PT878 Ultrasonic FlowmeterGUI ControlsPT878 Ultrasonic FData Logger1 Megabyte storage 100,000 recordsFrom 1 to 12 items per logMultiple logs can run simultaneouslyLog interval from 1 second to 99 minutesProgrammable Start and End Date/TimeCyclic Logs

16、Error logsPT878 Ultrasonic FlowmeterData LoggerPT878 Ultrasonic FlFlash MemoryInstall new program in minutes over IRNo EPROMs to changePT878 Ultrasonic FlowmeterFlash MemoryPT878 Ultrasonic FIrDA - Compatible WirelessCommunicationsInfrared data transferUp to 115KbpsUp to 1 meter rangeDrag & Drop fil

17、e transfersAutomaticNo settingsNo cable adapters requiredPT878 Ultrasonic FlowmeterIrDA - Compatible WirelessPT8BatteryNiMH rechargeable9 to11 hour run time (longer than NiCd)6 hour rechargeNone of the memory problems associated with NiCdFewer charge cycles than NiCdNiCd performs better in cold NiCd

18、 or disposable AA alkaline cells can be used instead of NiMHPT878 Ultrasonic FlowmeterBatteryPT878 Ultrasonic FlowmeBatteryContinuous battery level gaugeSimple icon indicates chargeUniversal charger 100-250VACPT878 Ultrasonic FlowmeterBatteryPT878 Ultrasonic FlowmeBatteryRun time up to 11 hours, dep

19、ending on features selected.Run time is reduced by:Prolonged use of the backlightLoop-powered 4-20mA transmittersHigh resistance loads on 4-20mA outputRun time is increased by:Using Sleep modePT878 Ultrasonic FlowmeterBatteryPT878 Ultrasonic FlowmePT878 Ultrasonic FlowmeterEnvironmentalMeets IP67 ra

20、tingWithstands submersion in waterDurable polymer bootPrevents damage if droppedIntegrated wire standPT878 Ultrasonic FlowmeterEnviPT878 Ultrasonic FlowmeterMeter SetupSelect UnitsSelect TransducerSelect PipeSelect LiningSelect FluidAdjust PathCorrection FactorsSave to a SitePT878 Ultrasonic Flowmet

21、erMetePT878 Ultrasonic FlowmeterSelect UnitsThe PT878 can default to either Metric or English units.From the Meter menu, select Units.Press OK to use the new settings.PT878 Ultrasonic FlowmeterSelePT878 Ultrasonic FlowmeterSelect TransducerSelect Wetted or Clamp-onChoose Transducer from ListList onl

22、y shows applicable transducersAll parameters filled in automaticallyChoose SPECIAL to enter customer parametersAllows each parameter to be specifiedPT878 Ultrasonic FlowmeterSelePT878 Ultrasonic FlowmeterSelect PipeSelect Pipe Material from ListPipe Sound Speed automatically filled inSelect OTHER fo

23、r unlisted materialEnter Sound SpeedEnter DimensionsOuter Diameter (OD) or Circumference (ODxPI)Wall thicknessPT878 Ultrasonic FlowmeterSelePT878 Ultrasonic FlowmeterSelect PipeIf pipe material has a schedule, ID can be used to automatically enter dimensions.Uses ANSI (English) or DIN (metric) sched

24、ule.Schedule Materials:Stainless SteelCarbon SteelCast IronPVCCPVCPT878 Ultrasonic FlowmeterSelePT878 Ultrasonic FlowmeterSelect LiningChoose lining material from list, or Other to specifyLining option is not available when using Wetted transducersPT878 Ultrasonic FlowmeterSelePT878 Ultrasonic Flowm

25、eterSelect FluidEnable/Disable Tracking WindowsUse for fluids with unknown or highly variable sound speedSpecify minimum and maximum soundspeedChoose fluid from list or Other for unlisted fluidIf fluid not listed, specify the nominal soundspeed onlyPT878 Ultrasonic FlowmeterSelePT878 Ultrasonic Flow

26、meterSelect FluidFor Energy applications with water as fluid, specify the % Glycol concentrationPT878 Ultrasonic FlowmeterSeleAdjust PathFor clamp-on, Path length P and Axial length L are automatically calculated.Select the number of traverses.Spacing is automatically recalculated.Spacing can be cha

27、nged by entering a new value.PT878 Ultrasonic FlowmeterAdjust PathPT878 Ultrasonic FlFinish UpYour changes will not take effect until you:Press OK to keep all changesPress CANCEL to discard all changesPT878 Ultrasonic FlowmeterFinish UpPT878 Ultrasonic FlowCorrection FactorsReynolds CorrectionUse a

28、single value for Kinetic Viscosity (K/V).Table option is not availablePT878 Ultrasonic FlowmeterCorrection FactorsPT878 UltrasCorrection FactorsK-Factor CorrectionUse a single value for K-Factor multiplierUse a Table to relate K-Factor to another measure.Only Velocity can be used to interpolate the

29、K-Factor.PT878 Ultrasonic FlowmeterCorrection FactorsPT878 UltrasSave to a Site FileTo keep the new settings, you must save them to a Site File:Choose Save Now to replace the settings in the current site.Choose Manager to create a new site.PT878 Ultrasonic FlowmeterSave to a Site FilePT878 UltraSite

30、 ManagerUse the Site Manager to:Save settings to a new site.Use and existing site.Delete sites.Rename sites.Print or Transfer sites.PT878 Ultrasonic FlowmeterSite ManagerPT878 Ultrasonic FSite ManagerOpen the Site Manager menu by pressing Menu, Enter.Choose Save As to name the site and store it.PT87

31、8 Ultrasonic FlowmeterSite ManagerPT878 Ultrasonic FSite ManagerEnter a file name of up to 8 characters:Use arrows to move around the grid.Press Enter to select the character.Use Delete to erase a character.Press OK when done.Hint: A descriptive Site Message can be entered from the Site MenuPT878 Ultrasonic FlowmeterS