IZINDABA

Ikesi lesifunda elibunjiwe (MCCB) luhlobo lwedivayisi yokuvikela kagesi esetshenziselwa ukuvikela isekethe kagesi kusuka kumanje oweqile, ongadala ukulayishwa ngokweqile noma isifunda esifushane. Ngesilinganiso samanje esifinyelela ku-1600A, ama-MCCBs angasetshenziselwa izinhlobonhlobo zezintambo nobuningi obunamasethingi ohambo ongaguquguqukayo. Lawa ma-breaker asetshenziswa esikhundleni sama-miniature breakers (ama-MCB) ngezinhlelo ezinkulu ze-PV ngenhloso yokuhlukaniswa kohlelo nezinjongo zokuvikela.

Isebenza kanjani i-MCCB

I-MCCB isebenzisa ithuluzi lokuzwa lokushisa (i-elementi eshisayo) enedivayisi yamanje ezwela amandla kagesi (i-elementi kazibuthe) ukuhlinzeka indlela yohambo ngezinhloso zokuzivikela nokuzihlukanisa. Lokhu kwenza i-MCCB ikwazi ukuhlinzeka:
• Ukuvikelwa ngokweqile,
• Ukuvikelwa Kwephutha Likagesi emigqonyeni emifushane yesifunda
• Isishintshi Sikagesi sokunqanyulwa.

Ukuvikelwa ngokweqile

Ukuvikelwa kokugcwala ngokweqile kunikezwa yi-MCCB ngengxenye ebucayi yezinga lokushisa. Le ngxenye empeleni ingukuthintana kwe-bimetallic: oxhumana naye oqukethe izinsimbi ezimbili ezikhula ngamanani ahlukene lapho evezwa ukushisa okuphezulu. Ngesikhathi sezimo ezijwayelekile zokusebenza, oxhumana naye nge-bimetallic uzovumela amandla kagesi ageleze nge-MCCB. Lapho inani lamanje lidlula inani lohambo, oxhumana naye we-bimetallic uzoqala ukushisa agobe ngenxa yezinga elihlukile lokushisa lokukhula kokushisa ngaphakathi koxhumana naye. Ekugcineni, oxhumana naye uzogobeka kuze kube seqophelweni lokuphusha ibha yohambo futhi avule oxhumana nabo, kubangele ukuphazamiseka kwesifunda.

Ukuvikelwa okushisayo kwe-MCCB kuzoba nokubambezeleka kwesikhathi ukuvumela isikhathi esifushane se-overcurrent esivame ukubonakala kweminye imisebenzi yedivayisi, njengemisinga yokugijimela ebonwa lapho kuqala ama-motors. Lokhu kubambezeleka kwesikhathi kuvumela isekethe ukuthi liqhubeke nokusebenza kulezi zimo ngaphandle kokukhubeka i-MCCB.

Ukuvikelwa Kwephutha Likagesi emigqonyeni emifushane yesifunda

Ama-MCCB ahlinzeka ngempendulo esheshayo kwiphutha lesifunda elifushane, ngokuya ngomgomo we-electromagnetism. I-MCCB iqukethe ikhoyili ye-solenoid ekhiqiza insimu encane kagesi lapho yamanje idlula kwi-MCCB. Ngesikhathi sokusebenza okujwayelekile, inkambu ye-electromagnetic eyenziwe yikhoyili ye-solenoid ayinakwa. Kodwa-ke, lapho iphutha elifushane lesifunda livela esifundeni, i-current enkulu iqala ukugeleza nge-solenoid futhi, ngenxa yalokho, kuyasungulwa insimu enamandla kagesi eheha ibha yohambo futhi ivule oxhumana nabo.

Shintsha kagesi ngokunqanyulwa

Ngaphezu kwezinqubo zokukhubeka, ama-MCCB angaphinde asetshenziswe njengokushintshwa kokunqanyulwa mathupha uma kwenzeka kusebenza okuphuthumayo noma kokulungisa. I-arc ingakhiwa lapho oxhumana naye evula. Ukulwa nalokhu, ama-MCCB anezindlela zokuhlakaza i-arc zangaphakathi zokucima i-arc.

Ukucacisa Izici ze-MCCB Nezilinganiso

Abenzi be-MCCB kudingeka banikeze izici ezisebenzayo ze-MCCB. Eminye yemingcele ejwayelekile ichazwe ngezansi:
Kulinganiswe ngo-Frame yamanje (Inm):
Isilinganiso samanje esiphezulu i-MCCB esilinganiselwe ukusisingatha. Okwamanje uzimele olinganisiwe uchaza umkhawulo ongaphezulu webanga lamanje lohambo olungaguquguqukayo. Leli nani linquma usayizi wozimele wephuli.
Kukalwe Okwamanje (Ku):
Inani lamanje elilinganisiwe linquma ukuthi i-MCCB ihamba nini ngenxa yokuvikelwa ngokweqile. Leli nani lingaguqulwa, lifike kumkhawulo wamanje wohlaka olinganisiwe.
Kulinganiswe ngo wokuvala Voltage (Ui):
Leli nani libonisa amandla aphezulu i-MCCB engamelana nawo ezimweni zebhu. Amandla kagesi alinganisiwe we-MCCB ngokuvamile aphansi kunaleli nani ukuhlinzeka ngomugqa wokuphepha.
Kukalwe Ukusebenza Voltage (Ue):
Leli nani yi-voltage elinganiselwe yokusebenza okuqhubekayo kwe-MCCB. Ngokuvamile kufana noma kusondele kumandla wesistimu.
Kukalwe Impulse Ukumelana Voltage (Uimp):
Leli nani lingamandla we-peak wesikhashana owephuka isekethe angamelana nokushintsha ama-surges noma iziteleka zombani. Leli nani linquma amandla e-MCCB okumelana nama-voltages wesikhashana. Usayizi ojwayelekile wokuhlolwa komfutho yi-1.2 / 50µs.
Ukusebenza Komthamo Wokuqhekeka Kwesikhashana (Izithonjana):
Leli iphutha lamanje eliphakeme kakhulu i-MCCB engalisingatha ngaphandle kokulimala unomphela. Ama-MCCBs avame ukusetshenziswa kabusha ngemuva kokuphazanyiswa kwephutha uma nje engeqi leli nani. Ukuphakama kwe-Ics, ukuthembela kwesekethe kunokwethenjelwa.
Amandla Okuphula Isekethe Elifushane (Icu):
Leli inani lamanje lamaphutha eliphakeme kakhulu i-MCCB engalisingatha.Uma iphutha lamanje lidlula leli nani, i-MCCB ngeke ikwazi ukukhubeka. Kulesi sehlakalo, enye indlela yokuvikela enamandla okuphuka kakhulu kufanele isebenze. Lokhu kukhombisa ukwethembeka kokusebenza kwe-MCCB.Kubalulekile ukuqaphela ukuthi uma iphutha lamanje lidlula i-Ics kepha lingadluli ku-Icu, i-MCCB isengalisusa iphutha, kepha ingalimala futhi idinge ukushintshwa.
IMechanical Life: Leli inombolo enkulu yezikhathi i-MCCB engasetshenziswa ngesandla ngaphambi kokuba yehluleke.
Impilo kagesi: Leli inani eliphakeme lezikhathi i-MCCB engakhubeka ngalo ngaphambi kokuthi yehluleke.

Ukulinganisa i-MCCB

Ama-MCCB aseseketini kagesi kufanele alinganiswe ngokwezigaba zamandla okusebenza ezilindelekile zesekethe kanye namaphutha okungenzeka abe khona. Izindlela ezintathu eziyinhloko ngenkathi kukhethwa ama-MCCB yilezi:
• Umthamo wokusebenza olinganisiwe (Ue) we-MCCB kufanele ufane nogesi wesistimu.
• Inani lohambo lwe-MCCB kufanele lilungiswe ngokuya ngamanje ekhishwe umthwalo.
• Amandla wokwephula amandla e-MCCB kumele abe ngaphezulu kunale mibono yamaphutha yombono.

Izinhlobo ze-MCCB

Umdwebo 1: Ijika lohambo lohlobo B, C, no-D MCCBs

Isondlo se-MCCB

Ama-MCCB angaphansi kwemisinga ephezulu; ngakho-ke ukunakekelwa kwama-MCCB kubalulekile ekusebenzeni okuthembekile. Ezinye zezinqubo zokugcinwa kwazo zixoxwa ngezansi:

1. Ukuhlola Okubukwayo
Ngesikhathi sokuhlolwa okubonakalayo kwe-MCCB, kubalulekile ukubheka oxhumana nabo abakhubazekile noma imifantu ekheyini noma ekuvaleni. Noma yimaphi amamaki okusha lapho kuxhunyanwa noma kufakwa ikesi kufanele liphathwe ngokuqapha.

2. Ukuthambisa
Amanye ama-MCCB adinga ukuthambisa okwanele ukuqinisekisa ukusebenza kahle kweswishi yokunqamula ukunqamula nezingxenye ezihamba ngaphakathi.

3. Ukuhlanza
Ukungcola okufakwa kuma-MCCB kungalimaza izingxenye ze-MCCB. Uma ukungcola kufaka noma yikuphi ukuqhuba kungadala indlela yamanje futhi kubangele iphutha langaphakathi.

4. Ukuhlola
Kunezivivinyo ezintathu ezinkulu ezenziwa njengengxenye yenqubo yesondlo ye-MCCB.
Ukuhlolwa Kokumelana Nokuvikela:
Ukuhlolwa kwe-MCCB kufanele kwenziwe ngokunqamula i-MCCB nokuhlola ukwahlukaniswa phakathi kwezigaba nakuwo wonke amatheminali wokuphakela nowokulayisha. Uma ukumelana kokulinganisa okulinganisiwe kungaphansi kwenani elinconyelwe ukumelana nokunconywa komkhiqizi i-MCCB ngeke ikwazi ukuhlinzeka ngokuvikelwa okwanele.

Imininingwane Ukumelana
Lokhu kuhlolwa kwenziwa ngokuhlola ukumelana koxhumana nabo bakagesi. Inani elilinganisiwe liqhathaniswa nenani elicaciswe ngumenzi. Ngaphansi kwezimo ezijwayelekile zokusebenza, ukumelana noxhumana naye kuphansi kakhulu ngoba ama-MCCB kumele avumele ukusebenza kwamanje ngokulahleka okuncane.

Ukuvivinya Isivivinyo
Lokhu kuhlolwa kwenziwa ngokuhlola impendulo ye-MCCB ngaphansi kwezimo ezilinganayo ze-overcurrent kanye namaphutha. Ukuvikelwa okushisayo kwe-MCCB kuhlolwe ngokusebenzisa i-current enkulu nge-MCCB (300% yenani elilinganisiwe). Uma i-breaker yehluleka ukukhubeka, kuyinkomba yokwehluleka kokuvikelwa okushisayo. Isivivinyo sokuvikelwa kukazibuthe siqhutshwa ngokusebenza kwamapulse amafushane wamanje aphezulu kakhulu. Ngaphansi kwezimo ezijwayelekile, ukuvikelwa kukazibuthe kuyashesha. Lokhu kuhlolwa kufanele kwenziwe ekugcineni njengoba imisinga ephezulu inyusa izinga lokushisa loxhumana nabo nokufakwa ngaphakathi, futhi lokhu kungashintsha imiphumela yezinye izivivinyo ezimbili.

Isiphetho
Ukukhethwa okufanele kwama-MCCB ohlelo lokusebenza oludingekayo kubalulekile ekuhlinzekeni ukuvikelwa okwanele ezindaweni ezinemishini yamandla ephezulu. Kubalulekile futhi ukwenza imisebenzi yokulungisa njalo ngezikhathi ezithile futhi isikhathi ngasinye ngemuva kokuvulwa kwezinqubo zohambo ukuqinisekisa ukuphepha kwesiza kuyagcinwa.