Txhawm rau ua kom lub neej ntev ntawm cov tshuab hluav taws xob thiab lub cev muaj zog, kev ntsuas hluav taws xob tsis tu ncua yuav tsum tau ua. Tau ntau xyoo, tom qab ntau lub voj voog ntawm kev ua haujlwm, lub tshuab hluav taws xob tau raug cuam tshuam rau ib puag ncig xws li av, roj, kub, kev ntxhov siab, thiab kev co. Cov xwm txheej no tuaj yeem ua rau lub rwb thaiv tsev tsis ua haujlwm, ua rau poob ntawm kev tsim khoom lossis txawm tias hluav taws kub.
Lub cev muaj zog tiv thaiv kev tiv thaiv zoo muaj qhov ua haujlwm siab, feem ntau (ntawm qhov tsawg kawg nkaus) ntau dua li ob peb mega ohms (MΩ). Ib qho kev rwb thaiv tsev tsis zoo muaj cov rwb thaiv tsev qis dua. Qhov zoo tshaj plaws rwb thaiv tsev tiv thaiv rau lub tshuab hluav taws xob feem ntau txiav txim siab los ntawm cov chaw tsim khoom tshwj xeeb, qhov tseem ceeb ntawm daim ntawv thov uas siv lub cev muaj zog, thiab ib puag ncig nws nyob.
Nws yog qhov ua tau tsis tuaj yeem txiav txim siab txog cov cai rau qhov tseeb qhov tsawg kawg nkaus qhov hluav taws xob tiv thaiv tus nqi ntawm lub tshuab hluav taws xob vim qhov kev tiv thaiv nws txawv raws li kev tsim kho, qhov xwm txheej ntawm cov khoom siv rwb thaiv tsev siv, ntsuas voltage, qhov loj thiab hom. Txoj cai dav dav-ntawm-tus ntiv tes xoo yog 10 Megohm lossis ntau dua. Lub rwb thaiv tsev ntawm lub tshuab hluav taws xob tau hais tias nyob rau hauv qhov zoo yog tias:
Ntsuas rwb thaiv tsev tsis kam yog ntau dua lossis sib npaug rau 10MΩ
Hom rwb thaiv tsev Resistance Level rau Electric Motors
Tsis muaj txoj cai los txiav txim qhov tsawg kawg nkaus kev tiv thaiv tus nqi rau lub cev muaj zog. Feem ntau cov ntaub ntawv muaj yog empirical. Cov npe hauv qab no yog los ntawm grundfos, lub tuam txhab ua lag luam ntawm cov tshuab hluav taws xob:
