Txoj kev daws teeb meem ntawm tus pointer multimeter
Tam sim no muaj tsawg dua pointer multimeters siv tam sim no. Ib qho digital multimeter yog ib qho ntsuas ntsuas ntsuas tam sim. Nws siv 0.3 vib nas this los coj tus qauv los qhia qhov ntsuas ntsuas. Qee zaum cov txiaj ntsig ntawm txhua tus qauv tsuas yog zoo sib xws. Tsis yog tib yam nkaus. Qhov no tsis yooj yim rau kev nyeem cov txiaj ntsig raws li hom pointer.
Koob multimeter internal qauv yog yooj yim yog li tus nqi qis. Tsawg dua ua haujlwm. Kev saib xyuas yooj yim. Tshaj tam sim no thiab dhau-voltage muaj peev xwm. Hauv qab no peb tseem hais kom meej txog qhov pointer multimeter tsis ua haujlwm feem ntau siv txoj kev kho:
Ua ntej, kev txheeb xyuas thawj zaug ua ntej kev kho dua tshiab
Ua ntej overhaul, ua ntej ntawm tag nrho cov, nrog ib tug tshiab roj teeb nyob rau hauv txoj kab nrog rau cov kev cai ntawm lub rooj, lub multimeter teeb R × 1, R × 1 0, R × 100 los yog R × 1k cov ntaub ntawv, ob lub cwj mem luv luv kom pom seb lub koob tsis muaj qhov qhia, yog tias tsis muaj qhov qhia, feem ntau yog lub fuse (0.5A) lossis lub taub hau kauj qhib-circuit tshwm sim los ntawm. Txiav txim seb qhov txav coil puas yog siv cov hlau soldering rau vuam qhib ib kawg ntawm lub taub hau thaiv, thiab siv ib qho zoo multimeter teeb R × 1k cov ntaub ntawv los ntsuas nws qhov kev tiv thaiv, thaum saib seb lub kauj txav yog deflected, yog lub taub hau ntawm lub txav coil sab hauv tsis kam ntawm 0 Ω los yog infinity, lub kauj txav tsis txav, nws tuaj yeem txiav txim siab tias muaj qhov tsis ua haujlwm ntawm lub taub hau: 0 Ω sab hauv tsis kam qhia tias lub kauj kauj yog luv luv, infinity rau qhov qhib-circuit, koob tsis ruaj tsis khov rau lub zos luv luv-circuit los yog kev sib cuag tsis zoo, lub txav coil tsis deflection piav qhia Qhib Circuit Court lossis daig los ntawm cov khoom txawv teb chaws, yuav tsum tau kuaj xyuas ntxiv. Thib ob, overhaul DC voltage cov ntaub ntawv, DC tam sim no cov ntaub ntawv
Feem ntau, yog tias cov ntaub ntawv multimeter DC voltage yog ib txwm, feem ntau ntawm cov ntaub ntawv DC tam sim no kuj zoo li qub; yog tias cov ntaub ntawv DC voltage tsis zoo li qub, feem ntau ntawm cov ntaub ntawv DC tam sim no kuj yog ib qho teeb meem, uas feem ntau yog qhib Circuit Court. Ib txoj hauv kev tsim nyog ntau dua ntawm kev txiav txim siab yog pib sim los ntawm cov ntaub ntawv nruab nrab, MF{{0}}} muaj 50μA, 0.5mA, 5mA, 50mA, 500mA thiab lwm qib, nws tsim nyog rau pib los ntawm 5mA cov ntaub ntawv: yog tias cov ntaub ntawv 5mA tsis qhia txog qhov teeb meem yuav tsum nyob rau hauv cov ntaub ntawv 0.5mA lossis 50μA; Yog tias qhov kev nyeem ntawv loj, ces qhov txhaum yog nyob rau hauv cov ntaub ntawv 50mA lossis 500mA.
Thib peb, overhaul AC voltage cov ntaub ntawv, cov ntaub ntawv tiv thaiv
Hauv cov ntaub ntawv DC voltage, DC tam sim no cov ntaub ntawv raws li qhov qub, thiab tom qab ntawd ntxiv xyuas cov ntaub ntawv AC voltage thiab cov ntaub ntawv tiv thaiv. Qhov txhaum ntawm ob cov ntaub ntawv no feem ntau tshwm sim nyob rau hauv qhov yuam kev loj, pointer jitter, tsis muaj kev nyeem ntawv thiab kho rau xoom. Kev kho, koj yuav tsum xub qhib lub hau rov qab ntawm lub multimeter, saib seb puas muaj cov khoom siv hluav taws xob hlawv lossis xaim desoldering thiab lwm yam tshwm sim, thiab tom qab ntawd txheeb xyuas thiab txiav txim raws li daim duab schematic: yuam kev thiab tsis muaj kev nyeem ntawv, feem ntau cuam tshuam rau cov ntaub ntawv ntawm cov ntaub ntawv. Cheebtsam ntawm tus nqi ntawm lub luv luv Circuit Court, hauv zos luv luv-circuit, pwm tawg; pointer jitter, feem ntau yog ib qho ntawm ob lub raj rectifier lossis cov khoom sib txuas yog qhib-circuit; Omega tsis tuaj yeem hloov kho mus rau xoom, feem ntau yog lub roj teeb tsis txaus, lossis lub roj teeb, qhov zoo thiab qhov tsis zoo ntawm cov ncej ntawm oxidation, tiv thaiv kev tiv thaiv nce vim; Yog tias cov ntaub ntawv tus kheej tsis tuaj yeem hloov kho mus rau xoom (xws li R × 1 cov ntaub ntawv), tom qab kuaj xyuas thiab tsis muaj qhov yuam kev, feem ntau yog vim muaj kev tiv thaiv ntau ntxiv ntawm qhov hloov pauv, tuaj yeem ua ib qho me me ntawm cov roj nplua nyeem huv. ob peb lub lis piam ntawm reciprocal kev sib hloov, oxidation ntawm kev siv loj ntawm cov ntawv xuab zeb polishing.
