PT878超聲波流量計(jì)原理與安裝1.ppt

1、PT878超聲波流量計(jì)技術(shù)培訓(xùn),超聲波的概念與書語(yǔ)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(yǔ),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,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,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),tup = 超聲波被流體減速,tdn = 超聲波被流體

2、加速,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,夾裝式傳感器,折射原理 Snells Law,c1=傳感器內(nèi)傳播速度 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,c1,1,c2,2,3,c3,L,S,W.T.,Classic “clamp-on” approach,PT878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2,1.OKS傳感器夾具 2.CRS和CPT傳感器夾具 3.CF-LP傳感器夾具,所配傳感器的特性及用途,傳感器選用原則,1.溫度

3、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.,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.,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.,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:

4、多聲程:小管道,信號(hào)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,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),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,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,分辨率可能降低 0.電纜線開路 100.控制器故障

5、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,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,Features Large, Backlit LCD Simplified Keypad Graphical User Interface (GUI) Faster Update Rate Improved Peak Detection Larger, more powerful Data Logger XML-format Site Files Flash memory Simple Upgrades,

6、PT878 Ultrasonic Flowmeter,IrDA - compatible wireless data transfer Up to 11 hours run time per charge,LCD Display 240 x 200 resolution Room for 1 to 4 measurements Large signal waveform displays White EL Backlight,PT878 Ultrasonic Flowmeter,LCD Display 240 x 200 resolution Room for 1 to 4 measureme

7、nts Large signal waveform displays White EL Backlight,PT878 Ultrasonic Flowmeter,Keypad Rubberized keys Click action Simple universal layout Soft Function Keys,PT878 Ultrasonic Flowmeter,Graphical User Interface (GUI) Keeps related information together All choices visible at the same time,PT878 Ultr

8、asonic Flowmeter,GUI Controls Menus Related items grouped together Use to move through choices Use to change menus Press Enter to select,PT878 Ultrasonic Flowmeter,GUI Controls Tabs Quick access to related forms Use to select form Press Enter to open the form,PT878 Ultrasonic Flowmeter,GUI Controls

9、Buttons Selects between mutually exclusive choices Use to select button Press Enter to activate,PT878 Ultrasonic Flowmeter,PT878 Ultrasonic Flowmeter,GUI Controls Lists Choose from all applicable settings Use to move one item Use to scroll the list,PT878 Ultrasonic Flowmeter,GUI Controls Numeric Ent

10、ry Press Enter to begin entering digits Press to erase a digit Press Esc to cancel and restore original value Press Enter to accept the new value,Values can be entered or displayed in either Metric or English units without having to change meter defaults,PT878 Ultrasonic Flowmeter,GUI Controls Check

11、 Boxes Used to turn an option: On Off Press Enter to toggle,GUI Controls Function Keys Change according to form or menu active Press F1, F2, or F3 to select,PT878 Ultrasonic Flowmeter,GUI Controls Locale-Specific Change date, time, and decimal formats for local custom: MM/DD/YYYY DD-MM-YYYY YYYY-MM-

12、DD 11:59 PM 23:59 123.45 123,45,PT878 Ultrasonic Flowmeter,Data Logger 1 Megabyte storage 100,000 records From 1 to 12 items per log Multiple logs can run simultaneously Log interval from 1 second to 99 minutes Programmable Start and End Date/Time Cyclic Logs Error logs,PT878 Ultrasonic Flowmeter,Fl

13、ash Memory Install new program in minutes over IR No EPROMs to change,PT878 Ultrasonic Flowmeter,IrDA - Compatible Wireless Communications Infrared data transfer Up to 115Kbps Up to 1 meter range Drag & Drop file transfers Automatic No settings No cable adapters required,PT878 Ultrasonic Flowmeter,B

14、attery NiMH rechargeable 9 to11 hour run time (longer than NiCd) 6 hour recharge None of the memory problems associated with NiCd Fewer charge cycles than NiCd NiCd performs better in cold NiCd or disposable AA alkaline cells can be used instead of NiMH,PT878 Ultrasonic Flowmeter,Battery Continuous

15、battery level gauge Simple icon indicates charge Universal charger 100-250VAC,PT878 Ultrasonic Flowmeter,Battery Run time up to 11 hours, depending on features selected. Run time is reduced by: Prolonged use of the backlight Loop-powered 4-20mA transmitters High resistance loads on 4-20mA output Run

16、 time is increased by: Using Sleep mode,PT878 Ultrasonic Flowmeter,PT878 Ultrasonic Flowmeter,Environmental Meets IP67 rating Withstands submersion in water Durable polymer boot Prevents damage if dropped Integrated wire stand,PT878 Ultrasonic Flowmeter,Meter Setup Select Units Select Transducer Sel

17、ect Pipe Select Lining Select Fluid Adjust Path Correction Factors Save to a Site,PT878 Ultrasonic Flowmeter,Select Units The PT878 can default to either Metric or English units. From the Meter menu, select Units. Press OK to use the new settings.,PT878 Ultrasonic Flowmeter,Select Transducer Select

18、Wetted or Clamp-on Choose Transducer from List List only shows applicable transducers All parameters filled in automatically Choose SPECIAL to enter customer parameters Allows each parameter to be specified,PT878 Ultrasonic Flowmeter,Select Pipe Select Pipe Material from List Pipe Sound Speed automa

19、tically filled in Select OTHER for unlisted material Enter Sound Speed Enter Dimensions Outer Diameter (OD) or Circumference (ODxPI) Wall thickness,PT878 Ultrasonic Flowmeter,Select Pipe If pipe material has a schedule, ID can be used to automatically enter dimensions. Uses ANSI (English) or DIN (me

20、tric) schedule. Schedule Materials: Stainless Steel Carbon Steel Cast Iron PVC CPVC,PT878 Ultrasonic Flowmeter,Select Lining Choose lining material from list, or Other to specify Lining option is not available when using Wetted transducers,PT878 Ultrasonic Flowmeter,Select Fluid Enable/Disable Track

21、ing Windows Use for fluids with unknown or highly variable sound speed Specify minimum and maximum soundspeed Choose fluid from list or Other for unlisted fluid If fluid not listed, specify the nominal soundspeed only,PT878 Ultrasonic Flowmeter,Select Fluid For Energy applications with water as flui

22、d, specify the % Glycol concentration,Adjust Path For clamp-on, Path length P and Axial length L are automatically calculated. Select the number of traverses. Spacing is automatically recalculated. Spacing can be changed by entering a new value.,PT878 Ultrasonic Flowmeter,Finish Up Your changes will

23、 not take effect until you: Press OK to keep all changes Press CANCEL to discard all changes,PT878 Ultrasonic Flowmeter,Correction Factors Reynolds Correction Use a single value for Kinetic Viscosity (K/V). Table option is not available,PT878 Ultrasonic Flowmeter,Correction Factors K-Factor Correcti

24、on Use a single value for K-Factor multiplier Use a Table to relate K-Factor to another measure. Only Velocity can be used to interpolate the K-Factor.,PT878 Ultrasonic Flowmeter,Save to a Site File To keep the new settings, you must save them to a Site File: Choose Save Now to replace the settings

25、in the current site. Choose Manager to create a new site.,PT878 Ultrasonic Flowmeter,Site Manager Use the Site Manager to: Save settings to a new site. Use and existing site. Delete sites. Rename sites. Print or Transfer sites.,PT878 Ultrasonic Flowmeter,Site Manager Open the Site Manager menu by pr

26、essing Menu, Enter. Choose Save As to name the site and store it.,PT878 Ultrasonic Flowmeter,Site Manager Enter 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 Menu,PT878 Ultrasonic Flowmeter,Site Files Up to 32 sites stored in P