Circuit breaker current calculation method

Chekutanga verenga simba rose P remidziyo yese yemagetsi, mukuverenga kwehuwandu hwazvino A nhamba I=P/U,leakage switchinofanira kuva yakakura kudarika ikozvino, panofanira kuva neA imwe margin, kana mukuiswa kwezvimwe zvigadzirwa zvemagetsi hazvizokwanisi kumira.Residual leakage ikozvino mhuri 30MA inogona.Leakage switchkazhinji haisi yakawandisa kuchengetedza basa, kana iwe uchida kuchengetedza mutsara kune diki redunhu breaker, diki redunhu rinotyora harigone kusarudza rakakura zvakanyanya.Kazhinji, mhando C inoshandiswa.

Miniature circuit breakersshandisa nzira yakapusa yekuverenga ine zvimwe zvikanganiso zvisina kunyanyokura uye zvinogona kugamuchirwa muinjiniya:

(1) ye10/0.4kV voltage giredhi rediki redunhu breaker, inogona kufunga nezve yakakwira voltage divi reiyo pfupi yedunhu simba isingaperi (10KV divi repfupi redunhu simba rinowanzo 200 ~ 400MVA kana kutopfuura, saka maererano nekusingaperi kufunga, kukanganisa kuri pasi pegumi).

(2) Gb50054-95 "Low-voltage power Distribution Design Code" 2.1.2 zvisungo: "Kana huwandu hweiyo yakatemerwa ikozvino yemotor yakabatana padhuze nepfupi-circuit point inodarika 1% yenguva pfupi-circuit ikozvino, pesvedzero yemotokari mhinduro ikozvino inofanira kuiswa.Kana iyo pfupi-yedunhu ikozvino 30KA, tora 1% yayo, iyo inofanira kuva 300A.Iyo yakazara simba remota ingangoita 150KW, uye kana yatangwa panguva imwe chete, mhinduro iripo inosanganisirwa inofanirwa kunge iri 6.5∑In.

(3) iyo impedance voltage UK yemini-circuit breaker inomiririra divi pfupi redunhu (dunhu), kana divi rasvika parinoyerwa ikozvino, yepakutanga divi voltage ndiyo zana yepakati kukosha kwayo yakayerwa voltage.Naizvozvo, kana iyo yekutanga voltage iri yakayerwa voltage, yechipiri ikozvino ndiyo inotarisirwa ipfupi-yedunhu ikozvino.

(4) Diki divi redunhu rakatemerwa ikozvino Ite=Ste/1.732U Ste ndiko kugona kwediki redunhu rinotyora (KVA), Ue ndiro diki divi rakatemerwa voltage (hapana-mutoro voltage), Ue = 0.4kV kana 10 / 0.4kV, saka, rutivi rwechipiri rwakayerwa ikozvino rwe mini-circuit breaker inofanira kuverengwa sehuwandu hwe mini-circuit breaker X1.44 ~ 1.50.

(5) Zvinoenderana netsanangudzo yeUk mu (3), iyo pfupi-yedunhu ikozvino yedivi rekubatsira (nhatu-chikamu pfupi-dunhu) ndiyo tsananguro yeI (3) yeUk, uye pfupi-dunhu ikozvino divi rekubatsira (nhatu-nhanho pfupi-dunhu) ndiI(3)=Ite/Uk, inova yakakosha kukosha kweAC.

(6) Pasi pezvakafananamini-circuit breakerkugona, kana paine dunhu pfupi pakati pezvikamu zviviri, ipapo I(2)=1.732I(3)/2=0.866I(3)

Iko kuverenga kuri pamusoro ndiko kukosha kwazvino kweiyo pfupi redunhu pakubuda kweiyo miniature circuit breaker, inova ndiyo yakaipisisa tsaona yedunhu.Kana paine chinhambwe pakati peiyo pfupi yedunhu point uye mini-circuit breaker, funga nezve mutsara impedance.