Kev soj ntsuam ntawm qhov yuam kev voltage ntsuas los ntawm digital multimeter thiab analog multimeter
Yog hais tias qhov ntsuas hluav taws xob yog lub zog lag luam, uas yog, 50Hz alternating tam sim no, thiab ob lub ntsuas hluav taws xob tsim nyog, nws tsuas yog txhais tau tias qhov kev tiv thaiv sab hauv ntawm qhov ntsuas hluav taws xob loj dhau. Qhov loj tshaj plaws uas cuam tshuam rau qhov ntsuas qhov ntsuas hluav taws xob ntawm analog multimeters thiab digital multimeters ntawm tib zaus yog qhov sib txawv hauv kev ua haujlwm sab hauv, uas txawv heev thiab tsis yog tib qhov kev txiav txim siab. Thaum qhov kev tiv thaiv sab hauv ntawm qhov ntsuas hluav taws xob me me, qhov sib txawv tsis pom tseeb. Thaum qhov kev tiv thaiv sab hauv ntawm qhov ntsuas hluav taws xob loj, qhov ntsuas ntsuas yuav txawv heev.
Hauv qhov no, nws muaj peev xwm hais tias qhov ntsuas hluav taws xob tsis yog qhov tseeb 220V nyob hlau fais fab kab, lossis nws yog qhov ntsuas hluav taws xob tom qab cov hlau nyob dhau los ntawm qee yam khoom siv hluav taws xob, lossis nws yog qhov hluav taws xob ntawm lub plhaub ntawm cov hluav taws xob. khoom siv.
Tsis suav nrog cov peev txheej saum toj no, nws tsuas yog txhais tau tias ib qho ntawm ob lub moos tsis raug thiab xav tau kev kho thiab kho.
Muaj qhov yuam kev hauv kev ntsuas qhov voltage. Ua ntej tshaj plaws, koj yuav tsum paub seb qhov zaus ntawm qhov ntsuas AC voltage hauv Hz yog dab tsi? Puas yog qhov hluav taws xob no yog qhov ntshiab sine yoj?
Cov phau ntawv ntawm ntau yam multimeters tam sim no nyob rau hauv kev ua lag luam yog cim nrog cov lus teb zaus thiab AC waveform ntawm lub ntsuas thaum ntsuas AC voltage. Rau txhua yam zoo tib yam digital multimeters, cov lus teb zaus feem ntau yog 40-1000Hz, thiab nws yuav tsum yog sine yoj (distortion Tsawg dua lossis sib npaug li 1%). Kev ntsuas qhov tseeb tsis tau lees paub rau qhov ntsuas AC voltages tshaj qhov saum toj no. Qhov no yog vim AC / DC (alternating tam sim no / ncaj qha tam sim no) kev hloov pauv hauv cov khoom siv digital feem ntau yog tsim los siv lub zog qis dual ua haujlwm amplifier TL062. Qhov kev ua haujlwm amplifier no tau txwv GBW (tau txais cov khoom lag luam bandwidth), yog li cov tshuab digital multimeter tsis tuaj yeem ntsuas High-frequency AC voltage (tau kawg, nws kuj nyob ntawm seb qhov voltage faib cov resistor ntawm multimeter puas tau them).
Raws li qhov dav dav analog multimeter (nws yog thawj zaug tsim los ntawm cov neeg Asmeskas, nws tau 100 xyoo dhau los), nws cov qauv sab hauv yog qhov yooj yim heev, nrog lub ntsuas siab siab + diode rectifier + voltage faib resistor (ob peb analog multimeters nyob rau hauv kev txiav txim. Txhawm rau txhim kho qhov rhiab heev ntawm multimeter, ib qho kev ua haujlwm amplifier (AC amplifier) yog ntxiv ntawm lub taub hau meter thiab qhov sib faib hluav taws xob), yog li qhov ntsuas qhov tseeb ntawm qhov qub, pheej yig multimeter tsis tuaj yeem muab piv nrog cov digital multimeter. Qhov voltage-dividing resistor ntawm no hom 'meter' Feem ntau, capacitance them tsis ua, yog li cov lus teb zaus feem ntau yog 40-400Hz.
Qhov ob meters ntsuas tib qhov hluav taws xob AC nrog qhov sib txawv ntawm kaum tawm volts. Ua ntej, koj yuav tsum xyuas lawv cov voltage faib cov resistor tes hauj lwm saib seb puas yog ib qho ntawm cov resistors hloov tus nqi? Yog tias txhua yam zoo li qub, rau analog multimeter, koj tuaj yeem tshawb xyuas seb lub ntsuas ntsuas ntsuas tau taw tes rau xoom? Rau cov multimeter digital, koj tuaj yeem tshawb xyuas seb qhov ntsuas hluav taws xob puas ntawm AC voltage ntau yog xoob?
Los ntawm txoj kev, yog tias koj xav kom raug ntsuas qhov AC voltage ntawm arbitrary waveforms, nws raug nquahu kom yuav qhov muaj txiaj ntsig zoo (TRMS) multimeter. Qhov no multimeter tuaj yeem ntsuas qhov ntsuas AC voltage ntawm ntau yam waveforms xws li sine waves, daim duab peb sab nthwv dej, duab plaub, thiab lwm yam. Tsis muaj dab tsi ua.
Lub AC / DC hloov dua siab tshiab Circuit Court nyob rau hauv no portable tseeb RMS multimeter feem ntau yog tsim los siv TRMS integrated circuits AD736 thiab AD737 (tsim los ntawm Analog Devices, USA), yog li nws muaj peev xwm ntsuas AC voltages ntawm arbitrary waveforms.
