Ikhebula cross-kwesigaba sokubala. Itafula kubalwa ikhebula cross-section

Ukuze impilo ende futhi okuthembekile service ikhebula kubalulekile ukukhetha futhi abale. Izintambo zikagesi ezisobala Electric ukufakwa ikakhulukazi akhethiwe kwesigaba cross, ngokuyinhloko isipiliyoni. Kwesinye isikhathi lokhu kuholela amaphutha. Ukubala of ikhebula cross-section kuyadingeka, okokuqala kunakho konke, ngokulandela nokuphepha kagesi. Kungaba okungalungile, uma ubukhulu wire emincane noma emikhulu kunalokhu oyifunayo.

ikhebula cross-section eliphansi kakhulu

Leli cala iyona ayingozi kakhulu, kusukela okweqile babashayeli okusezingeni eliphezulu kwabantu kwamanje, kuyilapho ukwahlukanisa liyancibilika kanye nesifunda esincane kwenzeka. Iphinde zingase zephule imililo kagesi ukwenzeka, nasekumeni abasebenzi ungathola ngaphansi ukungezwani. Uma ikhebula ukufaka full wesifunda, ngokuvamile kakhulu usebenza ukuthi kuzodala ezinye kabi.

I Ingxenye evundlile ikhebula ingaphezu oyifunayo

Lapha isici main - umuntu kwezomnotho. Elikhulu cross-ingxenye bentambo, le ezibizayo ke. Uma wenza kanjalo wiring kulo lonke efulethini ngemajini ezinkulu, kungadla isizumbulu. Ngezinye izikhathi kungcono ukwenza entry main emikhulu cross-section, uma umthwalo kulindeleke ukuba eminye ukwandisa e inethiwekhi ekhaya.

Uma ikhebula ukubeka umshini ezifanele uzobe ogcwele kakhulu ulayini olandelayo lapho phi of them ngeke isebenze a full wesifunda.

Kanjani ukubala ikhebula cross-section?

Ngaphambi kokufaka, kungcono ukwenza ukubala we ikhebula cross-ingxenye umthwalo. Umqhubi ngamunye sinesikhundla esithile, okuyinto akufanele kube ngaphansi kuka-plug kagesi.

amandla ukubala

Indlela elula yokwenza ukubala umthwalo Imininingwane kwi phambili. ikhebula cross-kwesigaba sokubala umthwalo kuyehla kube ukuzimisela amandla ingqikithi abathengi. Ngamunye wabo sinenai ayo njengoba kuboniswe emzimbeni noma iphasiphothi. Khona-ke, amandla Imininingwane iyanda yi isici 0.75. Lokhu kungenxa yokuthi wonke amadivaysi ayikwazi luvulwe kanyekanye. Ngoba isinqumo sokugcina usayizi edingekayo kwetafula isetshenziselwa kubalwa kwesigaba ikhebula.

Ukubalwa esigabeni samanje ikhebula

Indlela esinembile kuyinto ukubala umthwalo lamanje. ikhebula cross-kwesigaba sokubala senziwa ekutholeni ukuhamba wamanje ngokusebenzisa ke. ifomula sisetshenziswa kunethiwekhi eyodwa-isigaba:

Mina _Calc. = P / (U _nom ∙ cosφ),

lapho P - amandla umthwalo, U _N. - the amapayipi voltage (220 V).

Uma okukhipha ingqikithi umthwalo asebenzayo yendlu 10 kW, kulinganiselwa zamanje mina _calc. = 10000/220 ≈ 46 A. Lapho ukubala kwenziwa wamanje ikhebula cross-section, ukulungiswa kwi ikhebula laying nemibandela (ecacisiwe kwezinye amatafula ekhethekile), kanye-sindisa lapho kagesi cishe phezulu nge 5 A. Ngenxa yalokho, mina _Calc. = 46 + 5 = 51 A.

Ubukhulu kunqunywa ngaphansi lwemibhalo wahlala. ikhebula cross-section ukubala besebenzisa ama-spreadsheet kwenza kube lula ukuthola ubukhulu esifanele eside wamanje kuvunyelwe. Ukuze ezintathu-core amakhebuli e indlu emoyeni, kubalulekile ukuba ukhethe inani bebheke elikhulu cross-ingxenye standard. Kuyinto 10 mm ^2. Ukuthi lolusuku ukubala kungaba self-isheke, usebenzisa i wokubala inthanethi - ekubalweni ikhebula cross-section, engatholwa kwamanye amasayithi.

Ukushisa ikhebula uma edlala ageleza

Lapho egijima umthwalo ku ikhebula uphehla ukushisa:

Q = mina ² RN W / cm

lapho mina - zamanje, R - kagesi resistivity, n - inombolo izintambo.

Kusukela inkulumo kusobala ukuthi inani amandla ezikhishwe silingane skwele wire siwela by wamanje.

Ukubalwa kuvunyelwe zamanje lokushisa Ukushisa umqhubi

Ikhebula ayikwazi unomphela kube evuthayo, kusukela ukushisa kwashabalala ku imvelo. Ekugcineni lizama ukuzivumelanisa Kumiswa futhi njalo lokushisa babashayeli.

Ukuze engaguquki-state inqubo ubuhlobo elandelayo ophethe:

P = Δt / ΣS = (t _x - t _cp) / (ΣS),

lapho Δt = t _f -t _cp - umahluko phakathi lokushisa aphakathi nendawo kanye imithambo ΣS - lokushisa ukumelana.

OKUVUMELEKILE zamanje okuqhubekayo egeleza ngokusebenzisa ikhebula, kusukela nkulumo:

Mina _DOP = √ ((t _ext - t _cp) / (RnΣS)),

lapho t _ext - lokushisa OKUVUMELEKILE Ukushisa izintambo (kuncike hlobo ikhebuli ukufakwa ikhebula). Imvama, kuba degrees 70 ku kwimodi ejwayelekile futhi 80 - esimweni esiphuthumayo.

Conditions of ukushabalalisa ukushisa ukugijima, ikhebula

Lapho ikhebula sibekwa yimuphi medium, ukushisa kunqunywa ukubunjwa yayo kanye nomswakama. Kubalwa inhlabathi resistivity kaningi ithathwa elilingana 120 ohms ∙ ° C / W (udaka isihlabathi ngesikhathi nomswakama ka 12-14%). Ukuze sicacise isidingo sokwazi ukubunjwa imvelo, khona-ke kungenzeka ukuthola ukumelana kokwaziswa amatafula. Ukuze kwandiswe conductivity ezishisayo we emseleni ligcwele udaka. Akuvunyelwe ukuba kulo doti ukwakhiwa kanye namatshe.

ukudluliselwa Heat kusukela ikhebula emoyeni sincane kakhulu. Luphinde zaba zimbi uma sibekwa isiteshi ikhebula lapho kukhona ezengeziwe izingqimba emoyeni. Lapha, umthwalo lamanje kumele kungancipha kuqhathaniswa nenani ebalisisiwe. I lobuchwepheshe izici izintambo futhi izintambo phambili kuvunyelwe lokushisa isekhethi 120 ° C PVC ukwahlukanisa. Ukumelana inhlabathi 70% wezindleko futhi iyona esemqoka kule izibalo. Ngokuhamba kwesikhathi, ukwanda ukwahlukanisa conductivity ngenxa omiswe yayo. Lokhu kumele kubhekwe izibalo.

Voltage ephonsa ikhebula

Ngenxa yokuthi babashayeli unayo i ukumelana kagesi, voltage out ingxenye at Ukushisa zabo, futhi kuziwa umthengi esingaphansi kwaba ekuqaleni komugqa. Ngenxa yalokho, ubude bentambo kulahleka engaba ngenxa nokushisa.

Ikhebula akumelwe kuphela ukukhetha kwesigaba esiphambanweni, ukuze kuqinisekiswe ukusebenza kwayo, kodwa futhi acabangele ibanga lapho amandla idluliswe. umthwalo ukwanda kuholela ekwandeni wamanje ngokusebenzisa umqhubi. Kulokhu, umonakalo ukwandisa.

On spotlight voltage encane sisetshenziswa. Uma kancane encishisiwe, kuba ngokushesha zile. Uma ukhetha izintambo okungalungile elise ezikude amandla supply amalambu bheka buthuntu. Voltage is kakhulu ziyancipha at esigabeni ngasinye ngokulandelana kwazo, futhi lokhu kubonakala ukukhanya. Ngakho-ke kudingekile ikhebula cross-section kanye ubude ukubala.

Isigaba ebaluleke kakhulu ikhebula kuyinto umthengi elise ngakolunye. Ukulahlekelwa ezibhekwa ikakhulu ngoba umthwalo.

Esikhathini indawo L umqhubi voltage iconsi kuyoba:

ΔU = (IzA + Qx) L / U _n,

lapho P no Q- asebenzayo futhi amandla esisheshayo, r futhi x - i ingxenye esebenzayo kanye L reactance, futhi U _n - okuzisholo voltage ukubaluleka lapho umthwalo ukusebenza ngokujwayelekile.

ΔU Esamukeleka kusukela ugesi ukuze imibono esemqoka musa idlule ± 5% ukukhanyisa Izakhiwo zokuhlala nendawo amandla izifunda. Kusukela okokufaka ekulahlekelweni umthwalo akufanele bube ngaphezu kuka-4%. Ngoba emide kufanele acabangele ukumelana exhasa ikhebula, okuyinto incike ibanga phakathi babashayeli eduze.

Umthengi Ukuxhumana

Imithwalo kungenziwa exhunywe ngezindlela ezahlukene. Izindlela ezilandelayo yizona ezivame kakhulu:

• ekupheleni inethiwekhi;
• Abathengi zabiwa nombala agudle;
• kungxenye ukwandiswa umugqa ixhunywe umthwalo nombala basakaza.

ISIBONELO 1

amandla Zikagesi 4 kW. Ubude ikhebula 20 m, le resistivity ρ = 0,0175 ∙ Ohm ^mm2.

Yamanje kunqunywa kusukela maqondana: Mina = P / U _nom = 4 ∙ 1000/220 = 18.2 A.

Khona-ke ethatha ithebula ekubalweni ikhebula cross-section, bese ukhetha ubukhulu ezifanele. Ukuze uthole wire yethusi kuzoba S = 1,5 mm ^2.

Ifomula ukubala kwesigaba ikhebula: S = 2ρl / R. Through kungenzeka ukunquma ukumelana kagesi ikhebula: R = 2 ∙ 0,0175 ∙ 20 / 1.5 = 0.46 ohms.

Ngokuvumelana nenani eyaziwayo R kungaba azimisele ΔU = IR / U ∙ 100% * 100 = 18.2 ∙ 0,46 / 220 ∙ 100 = 3.8%.

Waba yini umphumela wesibindi ukubala lingaphansi kuka-5%, bese ukulahlekelwa uzokwamukeleka. Endabeni ukulahlekelwa ezinkulu kufanele kwandiswe Ingxenye evundlile ikhebula i eduze, ukubaluleka ephakeme senhlobo ejwayelekile - 2.5 mm ^2.

ISIBONELO 2

Three ukukhanyisa wesifunda axhunyiwe parallel nomunye lwesigaba eyodwa ezintathu okhombisa umugqa, imithwalo olinganiselayo, ehlanganisa ikhebula ezine-wire 70 mm ² kuya ku-50 m ubude futhi conductive zamanje 150 A. Ngayinye okukhanyisa umugqa ubude 20 m sihamba wamanje 20 A.

ukulahlekelwa Interfacial at umthwalo oyibamba tifaka: ΔU = 150 ∙ _izigaba 0, 05 ∙ 0,55 = 4,1 V Manje kufanele unqume ukuthi ukulahlekelwa phakathi hlangothi futhi isigaba, kusukela ukukhanyisa ixhunywe 220 V: ΔU _{f n} = 4 1 / √3 = 2,36 V

Ngolunye lwalezo exhunyiwe ukukhanyisa wesifunda voltage iconsi lemali: ΔU = 18 ∙ 20 ∙ 0,02 = 7,2 V. Le ukulahlekelwa Imininingwane zinqunywa isamba U _tot = (2,4 + 7,2) / 230 = 4,2 100 ∙ %. Inani ibalwa ingaphansi ukulahlekelwa kuvunyelwe, okuyinto 6%.

isiphetho

Ukuvikela babashayeli okweqile ngesikhathi eside egijima umthwalo nge amatafula eyenziwe ikhebula cross-kwesigaba sokubala kuvunyelwe zamanje okuqhubekayo. Ngaphezu kwalokho, kubalulekile ukubala izintambo futhi izintambo iconsi voltage kuzo ayengasekho kuyinsakavukela. Ngakho nabo wafingqa ukulahleka wesifunda supply.