Kuv lub teb chaws lub zog siv hluav taws xob siv ob- cov nqi se: Ntxiv rau cov nqi ntsuas los ntawm cov ntsuas ntsuas, tus nqi hluav taws xob yooj yim raug them raws li qhov muaj peev xwm hloov pauv; Cov neeg siv loj dua kuj yuav tsum tau them ib qho - lub sijhawm muaj peev xwm nthuav dav tus nqi thaum ua haujlwm rau lawv cov transformers. Nrog rau txoj kev loj hlob ntawm kev lag luam hluav taws xob thiab kev siv hluav taws xob nce ntxiv, cov tswv lag luam ntiag tug thiab cov ntawv cog lus hloov pauv tau maj mam nyob ib feem ntau ntawm cov khoom siv hluav taws xob. Qhov no tau ua rau ntau yam kev dag ntxias ua haujlwm los ntawm cov tib neeg los txo lawv cov nqi hluav taws xob thiab nce lawv cov kev siv (tsuas yog hloov pauv lossis hloov cov npe hloov pauv). Lub zog hluav taws xob tawm tsam los saib xyuas qhov no zoo, thiab qee cov neeg siv nyiag ntau pua txhiab tus yuan hauv cov nqi hluav taws xob txhua xyoo.
Cov cuab yeej no yog ib qho cuab yeej siv ntau- ntsuas ntsuas, sib npaug rau ob qhov kev ntsuas cov khoom siv: lub tshuab hluav taws xob muaj peev xwm ntsuas hluav taws xob thiab lub ntsuas hluav taws xob cov yam ntxwv ntsuas ntsuas. Nws tuaj yeem ntsuas qhov tseeb ntawm cov khoom siv hluav taws xob ntau zaus ntawm ntau lub tshuab hloov pauv, suav nrog lub peev xwm, hom, tsis muaj-load tam sim no, tsis muaj-load poob, luv- Circuit Court (load) poob, thiab impedance voltage.
Cov khoom no muaj ntau yam zoo, nrog rau qhov me me, lub teeb yuag, kev ntsuas siab, kev ruaj ntseg zoo, thiab kev ua haujlwm yooj yim. Nws tuaj yeem hloov pauv tag nrho cov txheej txheem dhau los ntawm kev ntsuas qhov hloov pauv thiab muaj peev xwm siv ntau lub meters. Kev xaim yog yooj yim dua, thiab kev sim thiab kaw tau yooj yim dua, uas ua rau koj ua haujlwm tau zoo.
