Ntev npaum li cas yog cov av hauv av ntawm cov roj hmab roj hmab tawm qub roj hmab lev?
Qhov ntev ntawm lub grounding xaim ntawm anti-zoo li qub roj hmab lev yuav tsum tau txiav txim siab tswj hwm tus qauv thiab kev teeb tsa ib puag ncig tiag. Hauv qab no yog cov ntsiab lus ntawm cov ntsiab lus tseem ceeb:
1. Cov tub ntxhais muaj kev txwv ntawm lub pob zeb xov kav ntev
Xav Tau Tus Nqi Yuav Tsum
Tag nrho cov kev tawm tsam ntawm cov xaim xaim hauv av yuav tsum tau ua kom tau raws li qhov tsawg dua lossis muaj kev sib npaug ntawm cov hluav taws xob tsis sib npaug thiab kev nyab xeeb.
Yog hais tias tooj liab hlau (tiv taus yog hais txog 0. 0172ωω \/ m) yog siv, cov xaim ntev thiab hla ntu rau kev xam. Piv txwv li:
Qhov ntev tshaj plaws tau tso cai rau tooj liab xaim nrog kev hla ntawm thaj tsam ntawm 4mm² yog 18,3 meters (sib npaug ntawm 10⁶ω);
Qhov ntev tshaj plaws tau tso cai rau tooj liab xaim nrog ib thaj chaw hla ntawm 6 hli tau txuas ntxiv rau 27,5 meters.
Cov Khoom Siv Txuas
Qhov kev ua tau zoo ntawm cov xaim hluav taws xob yuav tsum tsis txhob qis dua qhov tsis kam ntawm cov roj hmab lev (feem ntau 10 ⁵ω) kom tsis txhob cuam tshuam tag nrho cov nyhav tawm ntawm cov hlau ntau dhau.
2. Scenario-raws li qhov ntev
1. Cov pa ua haujlwm \/ kuaj
Nws raug nquahu kom siv cov xaim xaim hauv av tsawg dua lossis sib npaug ntawm cov phom sij rau ntawm 2 hli) yog qhov muaj feem cuam tshuam txog kev pheej hmoo ntawm cov kev pheej hmoo ntawm cov kev pheej hmoo ntawm kev pheej hmoo ntawm kev nce ntxiv vim ntev ntev.
2. Kev lag luam loj-teev pw
Nws raug nquahu kom teeb tsa ib qho chaw hauv av txhua 8 feet (txog 2.4 meters) rau kev coj ua mats (tsis kam<10⁴Ω), and ground in sections to eliminate potential differences;
Qhov ntev ntawm txoj kab loj yuav tsum tsis pub tshaj 25 metres, thiab thaj chaw liab qab rau 95 hli (xws li tooj liab busbar) kom tau raws li qhov yuav tsum tau ua tag nrho.
3. Cov Khoom Siv Hluav Taws Xob
Mobile cov tsheb los yog cov khoom siv tau pom zoo kom siv cov xov hlau retractable nrog ib qho ntev ntawm {}} meters kom tsis txhob raug tsoo thiab tawg los ntawm lwm yam khoom.
III. Kev ua tau zoo thiab kev tsim nyog yuav tsum tau ua
Kev sim ua tom qab
Siv ib tug puv rau ntsuas qhov tsis kam ntawm ob qho kawg ntawm cov xaim hauv av. Tus nqi tsim nyog yuav tsum tsawg dua los yog sib npaug rau 15ω (kev ntsuas kev coj ua) thiab tsawg dua lossis sib npaug ntawm 1m11 (system).
Kev saib xyuas ib txwm
Txheeb xyuas cov oxidation thiab hnav cov hlau hauv av txhua lub hli. Yog tias qhov kev tiv thaiv kev hloov kho dua li ± 10%, cov hlau yuav tsum tau hloov.