Dab tsi tuaj yeem yog qhov ua rau ntawm cov tshuab multimeter's tawg tsis kam cov ntaub ntawv?
Yog hais tias lub zog tiv thaiv ntawm lub tshuab multimeter, uas yog, tus pointer multimeter, puas lawm, tab sis lwm lub zog tuaj yeem kuaj tau ib txwm, nws txhais tau hais tias lub taub hau meter yuav tsum tsis txhob cuam tshuam. Raws li lub hauv paus ntsiab lus ntawm kev xeem cov ntaub ntawv tsis kam ntawm lub multimeter, nws muaj feem ntau tias shunt thiab voltage division precision resistor ntawm cov ntaub ntawv kuj raug hlawv tawm los yog tus nqi kuj hloov. Qhov feem ntau yuav ua rau muaj kev puas tsuaj rau cov ntaub ntawv tiv thaiv ntawm lub tshuab multimeter yog siv cov ntaub ntawv tiv thaiv raws li cov ntaub ntawv hluav taws xob los ntsuas qhov voltage. Yog li ntawd, ua ntej txhua qhov kev xeem, koj yuav tsum xub tau siv los saib seb lub iav raug xaiv raug, thiab txhim kho tus cwj pwm zoo.
Lub teeb thaiv hluav taws xob ntawm lub pointer multimeter tau tawg, thiab lwm yam iav tuaj yeem siv tau, qhia tias lub taub hau ntawm multimeter yog qhov zoo. Qhov no yog tshwm sim los ntawm kev siv tsis raug. Muaj ob qho laj thawj rau qhov no. Ib qho yog los ntsuas ob peb lub qhov hluav taws xob hluav taws xob nrog cov hluav taws xob me me hauv AC220V qhov hluav taws xob hluav taws xob tam sim no thaum lub DC tam sim no thaiv tau rub tawm (tsis hais hom pointer multimeter, lawv yog tag nrho cov hlau qhov txhab tiv thaiv, thiab lawv yog tag nrho cov ua los ntawm constantan.Qhov kev tiv thaiv hlau yog qhov txhab, thiab tus nqi kuj tsawg heev, piv txwv li, muaj 4 resistances hauv MF-47 hom, uas yog 0.54Ω, 5.4Ω, 54Ω, 540Ω). Tab sis dab tsi tus tswv tau hais tias lub multimeter tsuas muaj teeb meem nrog cov hluav taws xob thaiv, yog li tsis muaj teeb meem tshwm sim hauv cov iav no.
Qhov thib ob yog vim li cas; Rau cov neeg pib siv hluav taws xob thiab cov tshuab hluav taws xob, tom qab siv lub tshuab hluav taws xob multimeter lub ntsuas hluav taws xob ntsuas lossis kuaj xyuas lub voj voog, lawv tsis tig lub iav ntawm multimeter mus rau AC 500V iav, thiab tom qab ntawd ntsaws rau hauv 220V AC kab lossis lub qhov (socket). tshwm sim los ntawm alternating tam sim no nyob rau hauv lub xeem. Muaj ntau ntau tus qauv thiab cov chaw tsim khoom siv ntau tus pointer multimeters. Cov feem ntau siv thiab dav siv yog cov qub-fashioned 500 thiab MF-47 multimeters ua nyob rau hauv Nanjing.
①MF{{0}} multimeter muaj DC tam sim no iav (DCA), tag nrho tsib lub zog ntxiv rau 5A siab tam sim no nthuav dav, 0~0.05mA ~ 0.5mA ~5mA-50mA ~ 500mA.
②Nws muaj yim lub zog siv rau qhov hluav taws xob ncaj qha tam sim no (DCV) ntxiv rau qhov txuas txuas ntxiv uas tuaj yeem ntsuas DC2500V. 0 ~ 0.25V ~ 1V ~ 2.5V ~ 10V ~ 50V ~ 250V ~ 500V ~ 1000V ~ 2500V.
③ Muaj rau lub zog ntawm AC voltage (ACV), 0 ~ 10V ~ 50V ~ 250V ~ 500V ~ 2500.
④ Nws DC thaiv (Ω) tsib lub zog. R × 1Ω R × 10Ω R × 100Ω Rx1KΩ R × 10KΩ Kuj tseem muaj txoj kev buzzer thaum ntsuas (thaum tus nqi tsis kam yog 3 ~ 10Ω, lub buzzer yuav muab lub suab nrawm). Vim muaj qhov chaw tsawg, kev ua haujlwm xws li transistor DC amplification factor hFE, infrared remote control emission signal detection, and audio level DB raug rho tawm.
Ua ntej ntawm tag nrho cov, thaum ntsuas hluav taws xob tsis kam, ntxig cov xim dub coj mus rau hauv lub qhov → tus ncej tsis zoo ntawm lub taub hau meter → 20.2Ω resistor, 220.4Ω resistor, thiab 2430Ω resistor, tag nrho cov uas nyob rau hauv parallel nrog lub 'meter' taub hau. Lub sijhawm no, cov hlau lead kuaj liab tau muab tso rau hauv kaum lub qhov hluav taws xob ntawm multimeter, dhau los ntawm 1A kev tuav pov hwm lub raj → 1.5V qhuav roj teeb yog txuas nrog cov resistor, thiab tom qab ntawd dhau los ntawm 20k resistor → 1..7k resistor txhawm rau thaiv qhov xoom hloov pauv hloov pauv hloov pauv potentiometer → ib qho 500Ω resistor → Lwm lub meter yog calibrated R ntxiv → tus ncej zoo ntawm lub 'meter' yog ntxiv.
