I-SELV imele i-Safety Extra Low Voltage. Amanye amabhukwana wokufaka ugesi we-AC-DC aqukethe izexwayiso ezimayelana ne-SELV. Isibonelo, kungahle kube nesixwayiso mayelana nokuxhuma okukhiphayo okubili ochungechungeni ngoba amandla aphezulu avelayo angadlula izinga elichaziwe le-SELV, elingaphansi noma elilingana ne-60VDC. Ngaphezu kwalokho, kungahle kube khona izexwayiso mayelana nokuvikela ama-terminals okukhipha kanye namanye ama-conductor afinyelelekayo ekunikezelweni kwamandla ngezembozo zokuwavimbela ukuthi angathintwa ngabasebenzi abasebenza noma afushwe ngephutha ithuluzi eliwisiwe, njll.
I-UL 60950-1 ithi isekethe le-SELV "isekethe lesibili elakhiwe futhi lavikelwa ukuthi ngaphansi kwezimo ezivamile nezingafani, izintaba zalo azidluli inani eliphephile." "Isekethe yesibili" ayinakho ukuxhumana okuqondile namandla aphambili (ama-AC mains) futhi ithola amandla ayo nge-transformer, isiguquli noma idivaysi elinganayo yokuhlukanisa.
Amandla kagesi amaningi we-switchmode low voltage AC-DC anemiphumela efinyelela kuma-48VDC ahlangabezana nezidingo ze-SELV. Ngokukhipha okungu-48V ukusethwa kwe-OVP kungafika ku-120% kokuphakanyisiwe, okungavumela okukhiphayo ukuthi kufinyelele kuma-57.6V ngaphambi kokuthi ugesi uphele; lokhu kusazohambisana ne-60VDC ephezulu yamandla we-SELV.
Ngaphezu kwalokho, ukukhishwa kwe-SELV kutholakala ngokuhlukaniswa ngogesi ngokufakwa kabili noma okuqinisiwe phakathi kohlangothi lokuqala nolwesibili lwama-transformer. Ngaphezu kwalokho, ukuhlangabezana nokucaciswa kwe-SELV, amandla kagesi aphakathi kwanoma yiziphi izingxenye / ama-conductor amabili afinyelelekayo noma phakathi kwengxenye eyodwa / umqhubi ofinyelelekayo kanye nomhlaba akumele adlule inani eliphephile, elichazwa njenge-42.4 VAC peak noma i-60VDC isikhathi esingaphezu kwama-200 ms ngesikhathi esijwayelekile ukusebenza. Ngaphansi kwesimo sephutha elilodwa, le mikhawulo ivunyelwe ukukhuphukela phezulu kunani eliphakeme le-71VAC noma i-120VDC elingaphezu kwama-20 ms.
Ungamangali uma uthola ezinye izinkomba zikagesi ezichaza i-SELV ngokuhlukile. Izincazelo / izincazelo ezingenhla zibhekisa ku-SELV njengoba kuchazwe yi-UL 60950-1 kanye nezinye izinkomba ezihambisanayo eziphathelene namandla kagesi aphansi.
Isikhathi Iposi: Jul-20-2021