{"id":3486,"date":"2026-06-10T09:00:00","date_gmt":"2026-06-10T01:00:00","guid":{"rendered":"https:\/\/eqsvq3fzct.wpdns.site\/blog\/dc-mccb-dc-molded-case-circuit-breaker-basic-guide\/"},"modified":"2026-10-20T10:47:25","modified_gmt":"2026-10-20T02:47:25","slug":"%d8%b1%d8%a7%d9%87%d9%86%d9%85%d8%a7%db%8c-%d8%a7%d8%b3%d8%a7%d8%b3%db%8c-%d9%82%d8%b7%d8%b9%da%a9%d9%86%d9%86%d8%af%d9%87-%d9%85%d8%af%d8%a7%d8%b1-%d8%ac%d8%b9%d8%a8%d9%87%d8%b4","status":"publish","type":"post","link":"https:\/\/w9-group.com\/fa\/blog\/dc-mccb-dc-molded-case-circuit-breaker-basic-guide\/","title":{"rendered":"\u0631\u0627\u0647\u0646\u0645\u0627\u06cc \u06a9\u0644\u06cc \u062f\u0631\u0628\u0627\u0631\u0647 DC MCCB (\u0642\u0637\u0639 \u06a9\u0646\u0646\u062f\u0647 \u0645\u062f\u0627\u0631 \u0628\u0627 \u0628\u062f\u0646\u0647 \u0642\u0627\u0644\u0628 \u062f\u0648\u0642\u0637\u0628\u06cc)"},"content":{"rendered":"<p>A DC MCCB enquiry needs more than current and a DC label. The available voltage, source fault behaviour, polarity and approved connection determine whether a breaker can interrupt the actual circuit.<\/p>\n<p><strong>DC arc interruption<\/strong> differs from AC because there is no periodic natural current zero. A valid DC rating therefore belongs to a specific device, voltage and connection arrangement. An AC rating cannot be converted by a guessed factor.<\/p>\n<p>\u0628\u0631\u0631\u0633\u06cc \u06a9\u0646\u06cc\u062f <a href=\"https:\/\/w9-group.com\/fa\/%d9%81%d9%88%d8%aa%d9%88%d9%86%db%8c%da%a9\/\">photovoltaic protection range<\/a> against the maximum DC voltage and permitted pole connection.<\/p>\n<h2>Define the source and maximum voltage<\/h2>\n<p>For PV, establish <strong>maximum operating voltage<\/strong> under the design conditions and parallel-source contributions. For batteries, obtain prospective fault current and stored-energy information. For rectifier-fed circuits, the source impedance and source time constant can affect interruption duty. These are not interchangeable assumptions.<\/p>\n<p>Record earthing and whether current direction can reverse. A polarity-sensitive device must follow its approved diagram. Even a non-polarity declaration does not permit arbitrary pole connections or every source application.<\/p>\n<p>\u0627\u06cc\u0646 <a href=\"https:\/\/w9-group.com\/fa\/blog\/%d8%af%d8%b1%da%a9-%d9%86%d9%82%d8%b4-mccb-%d8%af%d8%b1-%d8%ae%d8%b7%d9%88%d8%b7-%d8%aa%d9%88%d8%b2%db%8c%d8%b9-%d9%81%d8%aa%d9%88%d9%88%d9%84%d8%aa%d8%a7%d8%a6%db%8c%da%a9\/\">photovoltaic distribution guide<\/a> distinguishes PV-string assumptions from battery fault-current duties.<\/p>\n<figure class=\"wp-block-image\"><img decoding=\"async\" alt=\"Solar-storage engineer checking a DC feeder and molded-case circuit breaker in Phoenix\" src=\"https:\/\/w9-group.com\/wp-content\/uploads\/2026\/07\/wlm7dc-400a-2300-2p-3p-wlm7dc-series-photovoltaic-solar-type-molded-case-gallery-01-3.webp\" style=\"display:block;width:50%;max-width:50%;height:auto;margin:0 auto\"\/><\/figure>\n<h2>Match the rating to the approved pole arrangement<\/h2>\n<p>Read voltage-specific fault data for the exact model and permitted <strong>pole connection<\/strong>. Multiple poles may have a specified series arrangement; that is a manufacturer instruction, not a field design shortcut. The protective conductor is not a switched live path.<\/p>\n<table>\n<thead>\n<tr>\n<th>Input<\/th>\n<th>\u0686\u0631\u0627 \u0627\u06cc\u0646 \u0645\u0633\u0626\u0644\u0647 \u0627\u0647\u0645\u06cc\u062a \u062f\u0627\u0631\u062f<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Maximum voltage<\/td>\n<td>Insulation and interruption duty<\/td>\n<\/tr>\n<tr>\n<td>Fault current<\/td>\n<td>Required breaking capacity<\/td>\n<\/tr>\n<tr>\n<td>Source behaviour<\/td>\n<td>Current rise and available energy<\/td>\n<\/tr>\n<tr>\n<td>Polarity and earthing<\/td>\n<td>Permitted connection and interruption path<\/td>\n<\/tr>\n<tr>\n<td>Operating current<\/td>\n<td>Conductor and thermal protection<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<figure class=\"wp-block-image\"><img decoding=\"async\" alt=\"Diagram of DC arc path, series poles and polarity markings in an MCCB\" src=\"https:\/\/w9-group.com\/wp-content\/uploads\/2026\/07\/wlm7dc-400a-2300-2p-3p-wlm7dc-series-photovoltaic-solar-type-molded-case-detail-01-1.webp\" style=\"display:block;width:50%;max-width:50%;height:auto;margin:0 auto\"\/><\/figure>\n<h2>Coordinate protection and isolation<\/h2>\n<p>An MCCB&#8217;s overcurrent release must protect conductors and coordinate with other devices. A PV string, battery feeder and converter input can need different settings and equipment. Confirm the declared isolation function and the actual means of safely separating every source for maintenance.<\/p>\n<table>\n<thead>\n<tr>\n<th>\u0627\u0637\u0644\u0627\u0639\u200c\u0646\u0627\u0645\u0647<\/th>\n<th>Specific review<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>PV combiner<\/td>\n<td>Parallel contributions and maximum array voltage<\/td>\n<\/tr>\n<tr>\n<td>Battery feeder<\/td>\n<td>Fault energy and current direction<\/td>\n<\/tr>\n<tr>\n<td>DC industrial load<\/td>\n<td>Starting or regenerative operation<\/td>\n<\/tr>\n<tr>\n<td>Converter circuit<\/td>\n<td>Manufacturer protection and isolation instructions<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<figure class=\"wp-block-image\"><img decoding=\"async\" alt=\"DC MCCB installed in a photovoltaic distribution enclosure\" src=\"https:\/\/w9-group.com\/wp-content\/uploads\/2026\/07\/wlm7dc-400a-2300-2p-3p-wlm7dc-series-photovoltaic-solar-type-molded-case-gallery-02-3-scaled.webp\" style=\"display:block;width:50%;max-width:50%;height:auto;margin:0 auto\"\/><\/figure>\n<h2>Procurement and acceptance<\/h2>\n<p>Request the full order code, DC rating table, permitted wiring, trip curves, terminals and installation limits. IEC 60947-2 context does not approve a device outside its declared duty. A photograph or generic solar description is insufficient evidence.<\/p>\n<p>For W9 selection, provide the source data and one-line diagram and ask for the exact supported configuration. Retain the approved drawing with the order and verify the delivered markings before installation.<\/p>\n<section id=\"faq\">\n<h2>\u0633\u0648\u0627\u0644\u0627\u062a \u0645\u062a\u062f\u0627\u0648\u0644<\/h2>\n<h3>Why is DC MCCB selection different from AC?<\/h3>\n<p>DC lacks periodic natural current zero and needs explicit interruption evidence for the source and connection. AC ratings do not establish DC capability.<\/p>\n<h3>What DC ratings are essential?<\/h3>\n<p>Confirm maximum voltage, operating current, fault capacity, polarity, permitted pole arrangement and relevant source conditions for the exact model.<\/p>\n<h3>Can a PV MCCB be used on a battery?<\/h3>\n<p>Only with explicit evidence for the actual battery fault duty and connection. A PV application label alone is insufficient.<\/p>\n<h3>Can I series-connect poles to raise voltage capacity?<\/h3>\n<p>Only as the exact manufacturer-approved diagram permits. Do not combine pole ratings arbitrarily.<\/p>\n<\/section>\n<h2>\u0645\u0646\u0627\u0628\u0639<\/h2>\n<ul>\n<li><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/66277\" rel=\"nofollow noopener\" target=\"_blank\">IEC 60947-2:2024 \u2014 \u0645\u062d\u062f\u0648\u062f\u0647 \u0645\u062d\u0635\u0648\u0644\u0627\u062a \u0642\u0637\u0639 \u06a9\u0646\u0646\u062f\u0647 \u0645\u062f\u0627\u0631<\/a>.<\/li>\n<li><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/65748\" rel=\"nofollow noopener\" target=\"_blank\">IEC 60364-7-712:2025 \u2014 \u062a\u0627\u0633\u06cc\u0633\u0627\u062a \u0628\u0631\u0642 \u0641\u062a\u0648\u0648\u0644\u062a\u0627\u0626\u06cc\u06a9<\/a>.<\/li>\n<li><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/107159\" rel=\"nofollow noopener\" target=\"_blank\">\u0646\u0633\u062e\u0647\u0654 \u062a\u0627\u0644\u06cc\u0641 \u0634\u062f\u0647\u0654 IEC 60947-3 \u2014 \u0633\u0648\u0626\u06cc\u0686\u200c\u0647\u0627\u060c \u0642\u0637\u0639\u200c\u06a9\u0646\u200c\u0647\u0627 \u0648 \u0642\u0637\u0639\u200c\u06a9\u0646\u200c\u0647\u0627\u06cc \u0642\u0637\u0639\u200c\u06a9\u0646<\/a>.<\/li>\n<\/ul>\n<p>\u0628\u0631\u0627\u06cc \u0627\u0646\u062a\u062e\u0627\u0628 PV \u06cc\u0627 DC\u060c, <a href=\"https:\/\/w9-group.com\/fa\/%d8%a8%d8%a7-%d9%85%d8%a7-%d8%aa%d9%85%d8%a7%d8%b3-%d8%a8%da%af%db%8c%d8%b1%db%8c%d8%af\/\">\u062a\u0645\u0627\u0633 \u0628\u0627 \u06af\u0631\u0648\u0647 W9<\/a> with maximum voltage, operating and <strong>\u0636\u0631\u06cc\u0628 \u062e\u0637\u0627<\/strong>, earthing and the intended pole connection.<\/p>","protected":false},"excerpt":{"rendered":"<p>\u0631\u0627\u0647\u0646\u0645\u0627\u06cc \u06a9\u0644\u06cc DC MCCB \u0628\u0631\u0627\u06cc \u067e\u0631\u0648\u0698\u0647\u200c\u0647\u0627\u06cc \u062e\u0648\u0631\u0634\u06cc\u062f\u06cc\u060c \u0630\u062e\u06cc\u0631\u0647\u0633\u0627\u0632\u06cc \u0648 OEM: \u0642\u0637\u0639 \u0642\u0648\u0633\u060c \u0642\u0637\u0628\u06cc\u062a\u060c \u0627\u0645\u062a\u06cc\u0627\u0632\u0627\u062a\u060c IEC 60947-2\u060c UL 489 \u0648 \u0628\u0631\u0631\u0633\u06cc\u200c\u0647\u0627\u06cc \u0645\u0631\u0628\u0648\u0637 \u0628\u0647 \u062a\u0623\u0645\u06cc\u0646 \u0645\u0648\u0627\u062f \u0627\u0648\u0644\u06cc\u0647.<\/p>","protected":false},"author":1,"featured_media":3762,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-3486","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"blocksy_meta":{"styles_descriptor":{"styles":{"desktop":"","tablet":"","mobile":""},"google_fonts":[],"version":8}},"acf":[],"_links":{"self":[{"href":"https:\/\/w9-group.com\/fa\/wp-json\/wp\/v2\/posts\/3486","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/w9-group.com\/fa\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/w9-group.com\/fa\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/w9-group.com\/fa\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/w9-group.com\/fa\/wp-json\/wp\/v2\/comments?post=3486"}],"version-history":[{"count":4,"href":"https:\/\/w9-group.com\/fa\/wp-json\/wp\/v2\/posts\/3486\/revisions"}],"predecessor-version":[{"id":4724,"href":"https:\/\/w9-group.com\/fa\/wp-json\/wp\/v2\/posts\/3486\/revisions\/4724"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/w9-group.com\/fa\/wp-json\/wp\/v2\/media\/3762"}],"wp:attachment":[{"href":"https:\/\/w9-group.com\/fa\/wp-json\/wp\/v2\/media?parent=3486"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/w9-group.com\/fa\/wp-json\/wp\/v2\/categories?post=3486"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/w9-group.com\/fa\/wp-json\/wp\/v2\/tags?post=3486"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}