Kev tsom xam ntawm cov cawv ntawm kev sib sau yuam kev ntawm kev ntsuas qhov ntsuas tau
Qhov loj dua sab hauv kev tawm tsam RV ntawm lub voltermeter, lub zog ze tus nqi ntsuas yog kom muaj qhov ntsuas hluav taws xob tseeb, qhov me dua qhov yuam kev, thiab siab dua qhov rhiab. Yog li ntawd, cov kev tiv thaiv ntau yam ntawm cov neeg sib xyaw yog ib qho ntsuas ntawm lub multimeter. Kab lus no rub cov lus xaus nram qab no los ntawm kev tshuaj ntsuam:
1. Yog tias ob tus neeg ua haujlwm nrog cov kev sib txawv ntawm voltities tau siv los ntsuas cov khoom sib txawv uas muaj ntau dua li ntawm qhov qis voltage rhiab.
2. Rau cov sib txawv ntawm tib co mottimeter ntau, qhov ntau dua qhov kev cuam tshuam hauv sab hauv, thiab qhov me dua ntawm qhov yuam kev ntawm kev ntsuas cov txiaj ntsig.
Ntawm no yog ib qho piv txwv los qhia txog qhov cuam tshuam ntawm kev ua yuam kev ntawm kev ntsuas cov txiaj ntsig. Qhov yuam kev ntsuas thaum ntsuas hluav taws xob voltage yog qhia hauv daim duab.
Nyob rau hauv daim duab, DC lub zog mov u {=10 v, nrog ib sab hauv kev tawm tsam r {1 k ω. Ib tug multimeter nrog lub voltage rhiab ntawm 20k ω / v yog xaiv los ntsuas qhov hluav taws xob no. Qhov yuam kev ntau npaum li cas cuam tshuam rau kev ntsuas cov txiaj ntsig? Yog tias peb xaiv 50V hloov 10V, nrog rau sab hauv kev tiv thaiv ntawm 1m ω, qhov kev cuam tshuam dab tsi ua rau qhov ntsuas tau?
Kev daws:
Thaum ntsuas ntsuas thawj zaug, xaiv 10v voltage ntau thiab sab hauv kev tawm tsam RV {} ω, ces:
Qhov txheeb ze yuam kev yog:
Thaum ntsuas ntsuas zaum ob, xaiv 50v voltage ntau thiab sab hauv kev tawm tsam RV {} m} m}, tom qab ntawd:
Qhov txheeb ze yuam kev yog:
Nws tuaj yeem pom tau tias qhov kev txheeb ze yuam kev muaj qhov cuam tshuam me me muaj qhov ntsuas kom me me thaum ntsuas ntsuas lub sijhawm ntsuas. Uas yog hais, nyob rau hauv ntsuas ntsuas, txhawm rau kom ntseeg tau tias nws qhov yuam kev thiab txo qis dua ntau zaus kuj tseem tuaj yeem raug xaiv. Qhov no yog vim tias qhov loj dua cov voltage ntau, qhov ntau dua sab hauv kev tiv taus thiab ntau dua qhov hluav taws xob rhiab heev. Yog lawm, qhov ntsuas hluav taws xob feem ntau tsis tuaj yeem raug xaiv ntau dhau, txwv tsis pub tus pointer deflection lub yuav tsawg heev thiab kev nyeem ntawv yuav tsis muaj tseeb. Sab hauv kev tawm tsam ntawm AC fais fab mov yog feem ntau yog tsawg, thiab ib qho ntau ntau, thiab ntau ntau cov kev ntsuas pom tau siv ntsuas hluav taws xob.
From the above analysis, it can be concluded that when measuring voltage with a multimeter, it is preferable to have a higher internal resistance in the voltage range of the multimeter, as the meter head of the multimeter is connected in parallel with the circuit being measured. Qhov loj dua sab hauv kev tawm tsam ntawm lub meter meter, qhov me dua qhov cuam tshuam ntawm cov kev ntsuas ntawm qhov ntsuas tau, thiab siab dua qhov rhiab.
