Puas yog qhov tseeb rms tus nqi ntawm multimeter tseem ceeb?
Ordinary pointer multimeter lossis digital multimeter rau high-frequency voltage, ntsuas tam sim no yog ntau zaus. Tshaj li qhov ntau zaus lawv tsis tuaj yeem cuam tshuam qhov tseeb RMS tus nqi ntawm cov qauv waveforms siab. Nws yuav pom tseeb thaum koj saib cov kev qhia tshwj xeeb ntawm koj lub multimeter.
True RMS yog dab tsi?
Tsuas yog True RMS meter tuaj yeem ntsuas qhov voltage / tam sim no. Nws yog qhov nruab nrab tus nqi ntsuas ntsuas AC cov cim qhia los ntawm txoj kev grate: qhov nruab nrab ntawm qhov ntsuas qhov ntsuas x 1.11=kho rau RMS. True RMS Cov algorithm rau AC teeb liab ntsuas los ntawm True RMS meter yog: Root Mean Square algorithm=Tseeb RMS. Rau cov ntshiab sine yoj, tsis hais qhov tseeb RMS lossis qhov nruab nrab tus nqi ntsuas ntsuas tau raug, tab sis rau cov nthwv dej uas tsis yog sine xws li: square yoj, daim duab peb sab yoj, sawtooth yoj, tsuas yog qhov tseeb RMS meter tuaj yeem ntsuas qhov tseeb. Ntau ntawm cov khoom siv hluav taws xob niaj hnub no uas tau hloov pauv ntau zaus tsis yog sinusoidal, thiab muaj qhov tseeb RMS multimeter yog tib txoj hauv kev los ntsuas qhov tseeb tus nqi.
Yuav ua li cas ntsuas thiab nyeem tsis kam nrog multimeter
Nyob rau hauv kev kho cov hluav taws xob Circuit Court boards, Circuit Court boards uas nws resistive Cheebtsam account rau txog 50% ntawm tag nrho cov hluav taws xob Cheebtsam, yog hais tias lub Circuit Court muaj ib tug txhaum resistive Cheebtsam yog ib tug ntawm cov khoom uas peb yuav tsum tau ntsuas.
Yog li yuav ua li cas siv multimeter los ntsuas qhov tsis kam thiab nyeem tus lej ntawm qhov tsis kam? Hauv qab no kuv muab cov teeb meem rau koj txog qhov no, ua ntej ntsuas kev tiv thaiv peb tau zoo dua ua ob txoj haujlwm zeroing, ib qho yog pointer multimeter mechanical zeroing; qhov thib ob yog ohm zeroing. Tom qab kev ua haujlwm ntawm ob kauj ruam no koj tuaj yeem xaiv qhov tsim nyog tus lej sib npaug rau kev ntsuas kev tiv thaiv, vim tias cov ntaub ntawv multimeter kuj tsis sib xws, peb xaiv cov ntaub ntawv sib npaug feem ntau xav ua kom lub ntsuas ntsuas ntsuas nyob rau hauv qhov sib txawv ntawm qhov ntsuas. qhov zoo tshaj plaws, thiab qhov ze ntawm tus pointer yog mus rau nruab nrab ntawm txoj hauj lwm teev qhov tseeb dua. Kuv xav tias nws yog qhov zoo tshaj los ua tus pointer hauv qhov ntsuas ntawm 1/3 txog 2/3.
Kev Nyeem Ntawv
Cov txheej txheem ntawm kev nyeem ntawv multimeter tsis nyuaj, uas yog, kev nyeem ntawv ntawm lub taub hau 'meter' yog muab sib npaug los ntawm qhov sib npaug, uas yog, tus nqi ntawm cov resistor yuav tsum ntsuas. Piv txwv li, los ntsuas tus nqi ntawm cov resistor yog 47 ohms, ces qhov ntau ntawm "Rx10" ntawm cov ntaub ntawv ohms, ces Hou multimeter pointer taw tes rau txoj hauj lwm ntawm 4.7, qhov kawg nyeem ntawv yog 4.7 x 10 rau 47 ohms. Yog hais tias qhov ntsuas ntawm cov resistors loj tuaj yeem xaiv qhov kev tiv thaiv loj dua, xws li Rx1k lossis Rx10K, lawv nyeem cov nqi tsis kam ntawm tib txoj kev.
