Multimeter tuaj yeem ntsuas qhov tsis kam ntawm cov conductors thiab cov lus tuav tuaj yeem ntsuas qhov tsis kam ntawm insulators
Tus neeg xyuas pib / Insulator
Tus neeg xyuas pib: ib yam khoom siv hluav taws xob zoo
Insulators: cov khoom siv hluav taws xob tsis zoo (ceeb toom, tsis yog cov khoom uas tsis muaj hluav taws xob)
Cov khoom siv hauv peb lub neej yog: tooj liab, hlau, txhuas, kub, nyiaj, graphite, thiab lwm yam.
Cov insulators feem ntau hauv peb lub neej yog: yas, roj hmab, iav, ceramics, dej ntshiab, huab cua, ntau yam roj ntxhia ntuj, thiab lwm yam.
Ntawm no peb yuav tsum xyuam xim tshwj xeeb yog tias cov insulator yog cov khoom siv tsis zoo, tsis yog cov khoom siv hluav taws xob. Hais lus nruj me ntsis, tsis muaj cov khoom siv hluav taws xob kiag li. Plastics, piv txwv li, tuaj yeem punctured ntawm qhov kub thiab txias thiab yog li ua hluav taws xob. Yog li ntawd, cov insulators tau muab faib ua tsib qib raws li lawv qhov kub thiab txias: Y, A, E, B, F, H thiab C.
Ib yam li ntawd, cov insulators yuav raug punctured ntawm ntau dua voltages thiab yog li ua hluav taws xob. Yog li ntawd, txawm hais tias lub insulator conducts hluav taws xob yog txheeb ze rau ib qho voltage, qhov voltage hu ua lub insulator tus nqi voltage.
Los ntawm kev txhais, txawm hais tias ib tug hlau hlawv los yog tsis muaj me ntsis ua nrog rau qhov voltage. Tom qab ntawd vim li cas nws thiaj li yuav tsum tau kos lub ntsuas hluav taws xob? Qhov no yog vim hais tias cov hlau sab nraud ntawm daim tawv nqaij insulating muaj ib tug voltage kam rau ua ntau yam. Peb tuaj yeem nkag siab yooj yim tias thaum cov dej siab tshaj qhov ntau ntawm cov kav dej, ces cov yeeb nkab yuav raug puas tsuaj, cov dej sab hauv yuav txau. Ib yam li ntawd, thaum qhov hluav taws xob ntawm cov xaim hluav taws xob ntau dua li qhov ntau ntawm cov tawv nqaij rwb thaiv tsev, cov hluav taws xob rwb thaiv tsev yuav raug rhuav tshem, tam sim no yuav khiav tawm, feem ntau hu ua "kua dej".
Multimeter thiab Megohmmeter
Lub multimeter yeej siv Ohm txoj cai los ntsuas qhov tsis kam. Peb txhua tus paub tias thaum ntsuas qhov tsis kam, lub multimeter yog siv los ntawm 1.5V thiab 9V roj teeb. Thaum ob lub cwjmem txuas nrog lub resistor, qhov tam sim no nyob rau hauv lub 'meter' pib los ntawm lub zoo davhlau ya nyob twg ntawm lub roj teeb, ces hla dhau lub meter taub hau, lub resistor, thiab ces rov qab mus rau qhov tsis zoo davhlau ya nyob twg ntawm lub roj teeb. Raws li qhov loj me tam sim no ntawm lub taub hau 'meter', koj tuaj yeem txiav txim qhov loj me me, vim tias qhov voltage yog qhov tseeb, qhov loj me tam sim no nyob ntawm qhov loj me me.
Rau kev ntsuas qhov tsis kam ntawm tus neeg xyuas pib, qhov no zoo kawg nkaus; Tab sis rau kev ntsuas lub insulator, nws yuav tsis ua hauj lwm, vim hais tias seb lub insulator conducts los yog tsis nyob ntawm qhov voltage thiab kub. Piv txwv li, ib tug insulator ntawm 9V tsis yog conductive, yog li thaum ntsuas nrog ib tug multimeter, lub 'meter' ib txwm tsis muaj tam sim no los ntawm lub taub hau, yog li cov zaub kuj yog infinite. Tab sis yog tias koj txuas ntxiv siv qhov hluav taws xob ntau dua, nws yuav ua rau kev puas tsuaj. Yog li thaum ntsuas seb lub insulator yog conductive los yog tsis, ib tug voltage yog teev.
Lub megohmmeter muaj lub tshuab hluav taws xob sab hauv tes-cranked DC, thiab nyob ntawm qib voltage ntawm megohmmeter, cov zis voltage ntawm lub tshuab hluav taws xob sib txawv. 250V megohmmeters tuaj yeem tawm DC voltages ze rau 250V, 500V megohmmeters tuaj yeem tawm DC voltages ze rau 500V, thiab 1000V megohmmeters tuaj yeem tawm DC voltages ze rau 1000V... yog simulating qhov ntsuas seb cov hlau xaim hauv qab 500V DC voltage.
Yog hais tias ib tug tej kab nyob rau hauv megohmmeter 500V kev ntsuas tsis tshwm sim nyob rau hauv lub to, ces nyob rau hauv lub 300V voltage yuav txawm ntau yuav tsis tshwm sim nyob rau hauv lub to. Yog li thaum peb xaiv megohmmeter rau kev ntsuas, peb yuav tsum xyuas kom meej tias megohmmeter voltage theem siab dua qhov tseeb voltage ntawm kab. Tsis tas li ntawd, megohmmeter yog muab los ntawm DC, thiab peb nquag siv 220V yog AC, 220V AC ncov tuaj yeem ncav cuag 220 * 1.414=311 V. Yog li, peb yuav tsum xaiv 500V megohmmeter hauv kev ntsuas ntawm AC 220V kab rwb thaiv tsev.
Multimeter tsuas yog siv los ntsuas qhov loj ntawm qhov tsis kam ntawm tus neeg xyuas pib, ntsuas qhov loj ntawm qhov tsis kam ntawm cov insulator lossis dhau lossis tsis yuav tsum yog megohmmeter. Vim tias tsuas yog megohmmeter tuaj yeem hnov mob hauv qee qhov hluav taws xob, cov hluav taws xob insulator lossis tsis! Thaum cov khoom insulator puas tsuaj tshwj xeeb, xws li lub cev muaj zog coil rwb thaiv tsev yog qhov raug mob hnyav, cov xov tooj tooj liab txuas ncaj qha ua ke, ces cov multimeter kuj tuaj yeem ntsuas. Vim tias cov rwb thaiv tsev tau raug puas tsuaj tag, qhov kev sib txuas tau dhau los ua tus neeg xyuas pib.
