Imingcele ye-low voltage circuit breaker: isikhathi esifushane ukumelana namanje (Icw), isetshenziselwa ini le pharamitha?

Ukumelana nesikhathi esifushane (Icw):Ikhono le-aI-circuit breakerukumelana no-0.05, 0.1, 0.25, 0.5 noma 1s ngaphandle kokukhubeka kuvoltheji enikeziwe, i-short-circuit current, noma isici samandla.
Isilinganiso sesikhathi esifushane sokumelana nokumelana namanje, okubuye kwaziwe ngokuthi i-thermal stable current, intambo esebenza ngempumelelo isinqamuli sesifunda noma enye idivayisi engakwazi ukumelana nayo isikhathi esifushane esishiwo.Ubukhulu bayo bulingana nomthamo wesifunda esifushane esilinganiselwe futhi isikhathi ngokuvamile siyimizuzwana emi-3 noma emi-4.

I-Icw inkomba yokuhlola ukuzinza kukagesi nokuzinza okushisayo kwe-circuit breaker ohambweni lokulibaziseka olufushane.Owe-class B circuit breaker.Ngokuvamile, ubuncane be-VALUE be-Icw buthi:

Uma ku-≤2500A, ingu-12In noma i-5kA,

Uma Iku>2500A, ingu-30kA

(KWE-YUW1_2000, i-Icw ingu-400V, 50kA; ye-DW45_3200, i-Icw ingu-400V, 65kA).

I-Icw ilinganisele isikhathi esifushane ukumelana namanje:Umkhiqizi uthi i-RMS ibekezelelwa isikhathi esifushane esichazwe okwamanje kanye nesikhathi ingathathwa njenge-RMS ebekezeleleka kumkhiqizo isikhathi esilinganiselwe, ngaphansi kwezimo ezifanele, ngesethi ephelele yemishini nezinto zikagesi.Kodwa imvelo yemikhiqizo ehlukahlukene ayifani, incazelo yenani lamanje elilinganiselwe lokubekezelelana ngeke lifane ngokuphelele, umnyombo walo ikakhulukazi amaphuzu alandelayo:

• Ukuqinisekisa ukwethembeka kokunikezwa kwamandla esistimu;

• Ngesisekelo sokuqinisekisa ukwethembeka kwesistimu yokunikezwa kwamandla, ukuphepha komkhiqizo ngokwawo

Kusistimu yokusabalalisa i-voltage ephansi, umbane olinganiselwe wesekethe emfishane unqunywa i-short-circuit current engenzeka ohlelweni endaweni yokufaka kanye nesikhathi lapho umkhiqizo ngokwawo neminye imikhiqizo ohlelweni ingamelana namanje.

I-Iec60364-4-43 indinganiso yokuvikela isifunda esifushane sesistimu yokusabalalisa amandla icaciswe ngokucacile: nganoma yisiphi isikhathi ku-loop ngenxa yesifunda esifushane esibangelwa yiwo wonke amandla amanje, akufanele idlule okwamanje, ku-conductor yesistimu aweqi izinga lokushisa elivunyelwe umkhawulo. sesikhathi sokuphuka.

Kumasekhethi amafushane athatha isikhathi esingaphezu kwamasekhondi angu-5, isikhathi (t) sokuba ikhondakta ikhuphuke ukusuka kuzinga lokushisa elivamile elivumelekile lokusebenza ukuya kuzinga lokushisa eliphakeme lokushisa elivumelekile singabalwa cishe ngefomula elandelayo:

T = (k * S/I) I-coefficient yento engu-2K, indawo yekhondatha ye-S, inani lamanje le-short-circuit.

Ngenhla, khetha imishini enengcindezi ephansi elinganiselwe inani lamanje lokumelana nesikhathi esifushane, kusukela endaweni yokufaka yamanje ye-short-circuit yamanje, ikhondakta noma ezinye izinto zokusebenza ohlelweni ukusuka ekukhuphukeni kwezinga lokushisa ukuya kwezinga lokushisa zingamelana nomkhawulo wesikhathi, lezi zici ezimbili. ukucatshangelwa, ekunqumeni indawo enkulu yokufaka yamanje yesiyingi esifushane futhi isistimu ingamelana nobukhulu besikhathi samanje sesiyingi esifushane, Iphinde inqume ukubekezelelana kwesikhathi samanje kwemishini yamandla aphansi endaweni yokufaka.

Ngenxa yokuthi ukwakheka nokusetshenziswa kwemishini kagesi ehlukene kuhlukile, kunezidingo ezikhethekile zevelu yesikhathi samanje sesikhashana ngesisekelo sokwanelisa ukuphepha kohlelo:

• Okokusebenza kukagesi njengamabhasi, amakhabethe okusabalalisa amandla kagesi aphansi, namaswishi anqamulayo, inani lamanje lesekethe emfishane akufanele libe ngaphansi kunevelu yamanje yesekethe emfishane elindelwe endaweni yokufaka, futhi isikhathi somkhawulo wamanje wesifunda esifushane kufanele kungabi mfishane kunesikhathi sokusebenza sezinto ezisetshenziswayo ezivikelayo ohlelweni.

• Kuma-circuit breaker asebenzisa isigaba B, inani lamanje lokubekezelela iDemo akufanele libe ngaphansi kwevelu yamanje yesekethe emfishane elindelwe endaweni yokufaka, futhi isikhathi somkhawulo wamanje wokubekezelela iDemo akufanele sibe ngaphansi kunesikhathi sokusebenza sesistimu. -izinto ezisetshenziswayo zokuvikela ezisezingeni, futhi uqinisekise ukukhetha ngemishini yokuvikela esezingeni eliphansi.

Manje, umthwalo wokunikezwa kwamandla wesistimu kanye nokukhuphuka kwamanje kwesikhashana esifushane, ukwanda kwesistimu yebhasi yokusabalalisa, i-low-voltage yemishini kagesi miniaturization, uma nje ukuphishekela ukubekezelelana kwesikhathi esifushane samanje ngaphansi komkhawulo wesikhathi eside wenani eliphakeme, empeleni, akukho ukubaluleka okukhulu okusebenzayo.

Ngakho-ke ngokwezinga eliphezulu lokufaka amaphuzu wamanje wesifunda esifushane kanye namanye amadivaysi ohlelweni angakwazi ukumelana nomthamo omkhulu we-short-circuit yangaleso sikhathi, ukukhethwa okunengqondo kwemishini kagesi endaweni ephephile ngaphansi komkhawulo wesikhathi yenani lamanje lokumelana nesikhashana, ngokuvumelana namanani angu-0.5 s Icw ekuhlolweni kubonakala sengathi ikwazile ukuhlangabezana nezimfuneko zokuvikeleka kwesistimu nokusebenza kahle okuphezulu.