Digital multimeter ntsuas capacitance zoo lossis phem
1, nrog rau cov ntaub ntawv capacitance ncaj qha nrhiav tau
Qee qhov digital multimeter muaj qhov ua haujlwm ntawm kev ntsuas lub peev xwm, nws qhov ntau tau muab faib ua 2000p, 20n, 200n, 2μ thiab 20μ tsib cov ntaub ntawv. Kev ntsuas tuaj yeem tso tawm lub peev xwm ob tus pins ncaj qha rau hauv lub rooj ntawm Cx jack, xaiv qhov tsim nyog tuaj yeem nyeem tom qab cov ntaub ntawv tso tawm.
000p cov ntaub ntawv, tsim nyog rau kev ntsuas lub peev xwm tsawg dua 2000pF; 20n cov ntaub ntawv, tsim nyog rau kev ntsuas capacitance ntawm 2000pF thiab 20nF; 200n cov ntaub ntawv, tsim nyog rau kev ntsuas lub peev xwm ntawm 20nF thiab 200nF; 2μ cov ntaub ntawv, tsim nyog rau kev ntsuas capacitance ntawm 200nF thiab 2μF; 20μF cov ntaub ntawv, tsim nyog rau kev ntsuas lub peev xwm ntawm 2μF thiab 20μF.
Kev paub dhau los tau ua pov thawj tias qee cov qauv ntawm digital multimeter (xws li DT890B +) hauv kev ntsuas ntawm 50pF hauv qab qhov me me capacitance capacitor yuam kev yog qhov loj, qhov ntsuas ntawm capacitance qis dua 20pF yuav luag tsis muaj nqi siv. Lub sijhawm no, koj tuaj yeem siv txoj kev sib txuas series los ntsuas qhov me me tus nqi capacitance.
Txoj kev yog: thawj zaug nrhiav tau 220pF los yog li ntawm capacitance, nrog ib tug digital multimeter los ntsuas qhov tseeb muaj peev xwm ntawm C1, thiab ces yuav tsum tau ntsuas nyob rau hauv parallel nrog lub me capacitance yuav tsum tau ntsuas tawm ntawm nws tag nrho cov peev xwm ntawm C2, ces qhov txawv ntawm ob (C1 - C2) uas yog yuav tsum tau ntsuas lub peev xwm ntawm lub capacitor me me. Nrog rau txoj kev no los ntsuas 1 ~ 20pF ntawm me me capacitance yog qhov tseeb heev.
2, nrog kev tiv thaiv kev tiv thaiv
Kev xyaum tau pom tias kev siv digital multimeter kuj tuaj yeem soj ntsuam cov txheej txheem them nyiaj ntawm cov khoom siv hluav taws xob, uas yog qhov ua tau zoo ntawm cov digital kom muaj kev cuam tshuam cov kev hloov pauv ntawm kev them nqi hluav taws xob. Teem lub digital multimeter ntsuas tus nqi ntawm n lub sij hawm / thib ob, tom qab ntawd hauv kev soj ntsuam ntawm cov txheej txheem kev them nyiaj capacitor, txhua thib ob kom pom n ywj siab ntawm ib leeg thiab kev nce qib ntawm cov ntawv nyeem. Raws li cov lus qhia no ntawm digital multimeter, koj tuaj yeem kuaj lub capacitor thiab kwv yees qhov loj ntawm lub peev xwm.
Cov hauv qab no yog kev siv digital multimeter tiv thaiv cov ntaub ntawv tshawb pom ntawm cov capacitors, vim tsis tau teeb tsa cov ntaub ntawv capacitance ntawm qhov ntsuas yog qhov ua tau zoo heev. Txoj kev no tsim nyog rau kev ntsuas 0.1μF ~ phav phav microfarads ntawm lub peev xwm loj capacitors.
1. Kev ntsuas ntsuas
Cov multimeter digital yuav raug hu mus rau cov ntaub ntawv tiv thaiv tsim nyog, tus cwj mem liab thiab cwj mem dub tau nyob rau hauv kev sib cuag nrog lub ntsuas capacitor Cx ncej, ces tus nqi zaub yuav maj mam nce los ntawm "000" mus txog rau thaum cov zaub dhau lub cim "1 ". Yog tias ib txwm qhia "000", lub capacitor sab hauv luv Circuit Court; Yog hais tias ib txwm qhia overflow, lub capacitor yuav yog sab hauv qhib Circuit Court ntawm ncej, kuj tseem yuav raug xaiv thaum cov ntaub ntawv tiv thaiv tsis tsim nyog. Thaum kuaj xyuas electrolytic capacitors, nws yuav tsum tau muab sau tseg tias tus cwj mem liab (zoo them) yog txuas nrog lub davhlau ya nyob twg zoo ntawm lub capacitor, thiab tus cwj mem dub txuas nrog rau qhov tsis zoo ntawm lub capacitor.
2. Kev ntsuas txoj cai
Kev ntsuas lub hauv paus ntsiab lus ntawm cov capacitors nrog qhov tsis kam yog qhia hauv daim duab {{0}} (b). Kev ntsuas, qhov zoo fais fab mov los ntawm tus qauv resistor R0 mus rau qhov ntsuas capacitor Cx them, nyuam qhuav pib them lub sijhawm, vim Vc=0, yog li cov zaub "000". Nrog rau qhov maj mam nce hauv Vc, cov zaub tus nqi nce. Thaum Vc=2VR, lub ' meter ' pib tso saib cov cim hla "1". Lub sijhawm them nyiaj t yog lub sijhawm nws siv rau cov zaub hloov pauv ntawm "000" kom dhau, thiab lub sijhawm tuaj yeem ntsuas nrog lub ntsuas quartz.
