{"id":19098,"date":"2025-08-06T23:11:57","date_gmt":"2025-08-06T15:11:57","guid":{"rendered":"https:\/\/viox.com\/?p=19098"},"modified":"2025-08-06T23:11:59","modified_gmt":"2025-08-06T15:11:59","slug":"why-is-there-no-short-circuit-making-current-mentioned-in-the-mcb","status":"publish","type":"post","link":"https:\/\/test.viox.com\/tr\/why-is-there-no-short-circuit-making-current-mentioned-in-the-mcb\/","title":{"rendered":"Mcb'de Neden K\u0131sa Devre Ak\u0131m\u0131 Belirtilmiyor"},"content":{"rendered":"
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Do\u011frudan Cevap:<\/strong> MCB'ler (Miniyat\u00fcr Devre Kesiciler), IEC 60898 standartlar\u0131n\u0131n zorunlu k\u0131ld\u0131\u011f\u0131 \u00fczere, kesme kapasitelerini standart 2,1 ila 2,2 fakt\u00f6r\u00fcyle a\u015fan do\u011fal yapma kapasitesiyle tasarland\u0131klar\u0131 i\u00e7in k\u0131sa devre yapma ak\u0131m\u0131ndan bahsetmez. Bu yerle\u015fik g\u00fcvenlik marj\u0131, devre kapanmas\u0131 s\u0131ras\u0131ndaki asimetrik ar\u0131za ak\u0131mlar\u0131n\u0131 kar\u015f\u0131lamak \u00fczere yapma kapasitesinin otomatik olarak garanti edilmesi nedeniyle \u00fcreticilerin yaln\u0131zca kesme kapasitesini (Ics\/Icu) belirtmeleri gerekti\u011fi anlam\u0131na gelir.<\/p>\n

\"VOM2-125<\/p>\n

VIOX MCB<\/a><\/p>\n

MCB Yapma Ak\u0131m\u0131 ile Kesme Ak\u0131m\u0131n\u0131n Anla\u015f\u0131lmas\u0131<\/h2>\n

Elektrik tesisat\u0131n\u0131z i\u00e7in MCB se\u00e7erken, \u00f6zellikler listesinde kesme kapasitesinin belirtildi\u011fini ancak yapma ak\u0131m\u0131 de\u011ferlerinin gizemli bir \u015fekilde atland\u0131\u011f\u0131n\u0131 fark edeceksiniz. Bu bir ihmal de\u011fil\u2014g\u00fcvenli\u011fi sa\u011flarken se\u00e7imi basitle\u015ftiren kas\u0131tl\u0131 bir m\u00fchendislik tasar\u0131m\u0131d\u0131r.<\/p>\n

Yapma Ak\u0131m\u0131n\u0131 Kesme Ak\u0131m\u0131ndan Farkl\u0131 K\u0131lan Nedir<\/h3>\n

Yapma ak\u0131m\u0131<\/strong> bir MCB'nin mevcut bir ar\u0131za \u00fczerine kapan\u0131rken g\u00fcvenle kar\u015f\u0131layabilece\u011fi maksimum tepe ak\u0131m\u0131n\u0131 ifade eder. Bu kritik anda, DC bile\u015feni asimetrisi nedeniyle ak\u0131m, RMS kesme ak\u0131m\u0131n\u0131n 2,1 ila 2,2 kat\u0131na ula\u015fabilir.<\/p>\n

Kesme ak\u0131m\u0131<\/strong> MCB'nin devreden g\u00fcvenle kesip temizleyebilece\u011fi maksimum ar\u0131za ak\u0131m\u0131n\u0131 temsil eder. Her MCB \u00fczerinde Ics (hizmet kesme kapasitesi) veya Icu (nihai kesme kapasitesi) olarak yaz\u0131l\u0131 olan budur.<\/p>\n

Yapma ve Kesme \u0130\u015flemleri Aras\u0131ndaki Temel Farklar<\/h2>\n\n\n\n\n\n\n\n\n\n\n\n
\u00d6zellik<\/th>\nYapma \u0130\u015flemi<\/th>\nKesme \u0130\u015flemi<\/th>\n<\/tr>\n<\/thead>\n
Mevcut B\u00fcy\u00fckl\u00fck<\/td>\n2,1-2,2 \u00d7 RMS de\u011feri<\/td>\nRMS simetrik de\u011feri<\/td>\n<\/tr>\n
DC Bile\u015feni<\/td>\nMaksimum (100%)<\/td>\nVaries (0-100%)<\/td>\n<\/tr>\n
Contact Stress<\/td>\nElectromagnetic repulsion<\/td>\nArc erosion<\/td>\n<\/tr>\n
S\u00fcre<\/td>\nInstantaneous (<10ms)<\/td>\n10-20ms typical<\/td>\n<\/tr>\n
Critical Factor<\/td>\nMechanical withstand<\/td>\nYay s\u00f6nmesi<\/td>\n<\/tr>\n
Design Priority<\/td>\nRobust contacts<\/td>\nArc chute efficiency<\/td>\n<\/tr>\n
Standart Referans<\/td>\nIEC 60898-1 Clause 9.12.11<\/td>\nIEC 60898-1 Clause 9.12<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\"30A<\/p>\n

Why MCB Manufacturers Don\u2019t Specify Making Current<\/h2>\n

1. Built-in Safety Factor<\/h3>\n

MCBs are manufactured with making capacity automatically sized at 2.2 times their breaking capacity. When you select an MCB with 10kA breaking capacity, you\u2019re guaranteed it can make onto a fault current of 22kA peak.<\/p>\n

2. International Standard Requirements<\/h3>\n

IEC 60898-1 mandates that all MCBs must withstand making current at the prescribed ratio. Manufacturers cannot produce compliant MCBs without this capability, making separate specification redundant.<\/p>\n

3. Simplified Selection Process<\/h3>\n

By focusing on breaking capacity alone, you can select MCBs based on prospective fault current calculations without complex asymmetry factor calculations.<\/p>\n

Uzman \u0130pucu:<\/strong> Always verify your installation\u2019s prospective fault current using proper testing equipment. The breaking capacity must exceed this value with appropriate safety margin.<\/p><\/blockquote>\n

MCB Rating Classifications and Making Capacity<\/h2>\n\n\n\n\n\n\n\n\n\n\n
Breaking Capacity (Ics\/Icu)<\/th>\nAutomatic Making Capacity<\/th>\nTipik Uygulamalar<\/th>\n<\/tr>\n<\/thead>\n
3 kA<\/td>\n6.6 kA peak<\/td>\nResidential final circuits<\/td>\n<\/tr>\n
4.5 kA<\/td>\n9.9 kA peak<\/td>\nLight commercial circuits<\/td>\n<\/tr>\n
6 kA<\/td>\n13.2 kA peak<\/td>\nStandard commercial\/industrial<\/td>\n<\/tr>\n
10 kA<\/td>\n22 kA peak<\/td>\nHeavy industrial\/near transformer<\/td>\n<\/tr>\n
15 kA<\/td>\n33 kA peak<\/td>\nMain distribution boards<\/td>\n<\/tr>\n
25 kA<\/td>\n55 kA peak<\/td>\nIndustrial switchboards<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\"1P-4P<\/p>\n

Applications Where Making Current Matters Most<\/h2>\n

Near Transformer Installations<\/h3>\n

You need higher breaking capacity MCBs when installing circuits close to transformers where fault currents are maximum. The making capacity becomes critical during:<\/p>\n