Analog vs Digital Multimeter
Multimeter lossis multitester yog cov ntsuas ntsuas siv hauv cov khoom siv hluav taws xob, uas yog tsim los ua haujlwm ntawm ntau lub ntsuas ntsuas. Qhov ntsuas hluav taws xob, tam sim no, thiab kev tiv thaiv tuaj yeem ua tau siv cov kev xaiv sib txawv muaj nyob rau hauv ib qho Multimeter; Yog li, nws tseem hu ua VOM (Volt Ohm meter). Hauv cov qauv kim dua thiab qib siab, lub peev xwm thiab inductance kuj tuaj yeem ntsuas thiab tuaj yeem siv los txheeb xyuas cov pins ntawm cov khoom siv hluav taws xob xws li transistors thiab diodes.
Ntau txog Analog Multimeter
Analog Multimeter yog hom qub ntawm ob lub multimeters, thiab nws yog ib qho ammeter. Nws txoj haujlwm yog ua raws li lub caij nplooj ntoos hlav loaded txav coil mechanism nyob rau hauv ib lub hlau nplaum. Thaum ib tug tam sim no ntws los ntawm lub kauj, kev sib cuam tshuam ntawm induced magnetic teb nyob rau hauv lub kauj thiab cov hlau nplaum ruaj ruaj tsim ib tug quab yuam kom txav lub kauj. Lub koob txuas nrog lub coil txav proportional rau lub zog tsim, qhov twg lub zog yog proportional rau tam sim no ntws los ntawm lub kauj. Lub koob txav mus rau cov lej cim rau ntawm lub xov tooj, qhia txog tus nqi tam sim no dhau los ntawm lub kauj.
Txhawm rau ntsuas qhov hluav taws xob thiab qhov tsis kam, qhov hluav taws xob sab hauv txuas nrog rau cov khoom siv hluav taws xob ntxiv xws li tam sim no los ntawm lub kauj sawv cev rau qhov hluav taws xob lossis qhov tsis kam. Qhov no ntxiv circuitry kuj muab multimeter lub peev xwm los khiav lag luam ntawm cov nqi sib txawv. Piv txwv li, nrog ib tug multimeter nws muaj peev xwm ntsuas 20mV thiab 200V, tab sis lub teev yuav tsum tau teem raws li.
Cov zis (duab) ntawm analog multimeter yog lub sijhawm ua haujlwm tas mus li, qhov twg theoretically tus koob qhia tus nqi ntawm qhov tam sim ntawd. Yog li ntawd, analog multimeters tseem nyiam los ntawm qee cov kws tshaj lij vim nws cov lus teb ntawm lub sijhawm tiag tiag uas yog qhov tseem ceeb thaum ntsuas lub capacitor lossis inductor circuits. Qhov tsis zoo ntawm cov ntsuas ntsuas analog yog qhov yuam kev parallax uas lawv ua rau hauv kev nyeem ntawv thiab ncua sij hawm teb vim qhov inertia ntawm rab koob thiab cov txheej txheem. Qhov inertia no ua tau zoo thaum muaj suab nrov nyob hauv kev ntsuas; uas yog rab koob yuav tsis txav mus rau qhov hloov me me thaum ntsuas qhov voltage lossis tam sim no.
Cov Analog multimeters yuav tsum tau muab qhov hluav taws xob rau ntsuas qhov tsis kam; feem ntau yog siv AAA roj teeb. Nyob ntawm qhov tso zis hluav taws xob ntawm lub roj teeb thaum lub sijhawm (uas txo qis nrog lub sijhawm, tsis yog 1.5 V ib txwm), qhov ntsuas kev tiv thaiv yuav tsum tau hloov kho manually rau xoom.
Ntau Txog Digital Multimeter (DMM)
Digital Multimeter, uas yog hom tshiab ntawm ob lub multimeters, yog hluav taws xob tag nrho hauv kev ua haujlwm, thiab tsis muaj cov khoom siv hluav taws xob koom nrog hauv kev ntsuas. Tag nrho cov haujlwm ntawm lub cuab yeej yog raws li cov khoom siv hluav taws xob.
Hauv kev sib piv rau kev ua haujlwm ntawm analog multimeter, digital multimeter siv qhov hluav taws xob los ntes cov teeb liab tawm tswv yim. Tag nrho lwm yam kev ntsuas xws li tam sim no thiab kev tiv thaiv yog muab los ntawm qhov hluav taws xob hla qhov kev sim ua.
Digital multimeters tau txais ntau qhov qauv ntawm lub teeb liab nyob rau lub sijhawm luv luv thiab nruab nrab cov cim qhia kom muab qhov tseeb zoo dua. Lub teeb liab analog tau hloov mus rau hauv cov teeb liab digital los ntawm analog rau digital converter, uas yog qhov tseem ceeb tshaj plaws ntawm cov khoom siv hluav taws xob hauv multimeter, hauv lub multimeter. Txhawm rau txhim kho qhov tseeb ntxiv, feem ntau DMM qauv siv ib txoj hauv kev hu ua successive approximation register (SAR) hauv analog to digital conversion step.
Digital multimeters tso saib tus lej tus nqi raws li cov zis uas muaj qhov tseeb siab dua li cov analog multimeters. Tsis tas li ntawd, advanced digital multimeters muab cov yam ntxwv sib txawv tsis siv neeg kom tus neeg siv tsis tas yuav xaiv qhov ntau ntawm kev ntsuas manually. Tsis tas li ntawd, qhov no dhau los ua qhov kev nyab xeeb thiab. Txij li thaum tsis muaj qhov txav mus rau sab hauv, cov digital multimeters tsis muaj kev cuam tshuam los ntawm kev cuam tshuam xws li cuam tshuam nrog cov khoom nto.
Qhov txawv ntawm Analog thiab Digital Multimeter yog dab tsi?
• Analog multimeters muab qhov tso zis raws li kev nyeem ntawv ntawm qhov ntsuas tawm tsam tus taw tes, thaum cov khoom siv digital multimeter tso tawm yog nyob rau hauv cov lej tso tawm ntawm LCD.
• Analog multimeters muab qhov tso zis tas li thiab nqa qhov tsis paub meej ntau dua hauv kev ntsuas (kwv yees li 3%), thaum kev ntsuas digital multimeter muaj qhov tsis paub tseeb (kwv yees li 0.5% lossis tsawg dua). Digital multimeters yog qhov tseeb dua li analog multimeters.
• Digital multimeters muaj ntau yam kev ntsuas zoo dua li analog multimeters.
• Digital multimeters muaj cov yam ntxwv ntxiv xws li kev ntsuas hluav taws xob, qhov kub thiab txias, zaus, ntsuas suab ntsuas thiab kuaj pom cov khoom siv hluav taws xob semiconductor pins (transistor / diode).
• Analog multimeters yuav tsum tau calibrated manually, thaum feem ntau cov multimeters yog calibrated txiav ua ntej txhua qhov ntsuas.
• Analog multimeters yuav tsum tau teeb tsa rau qhov tshwj xeeb ntawm kev ntsuas manually, thaum qee qhov yuav tsum digital multimeters muaj qhov pib sib txawv.
• Analog multimeters xav tau kev xyaum los ntsuas qhov zoo, thaum lub tshuab multimeters tuaj yeem ua haujlwm txawm tias tus neeg tsis tau kawm.
• Analog multimeters tsawg dua thaum cov multimeters kim.
