{"id":6180,"date":"2026-08-28T13:00:55","date_gmt":"2026-08-28T05:00:55","guid":{"rendered":"https:\/\/www.yroele.com\/?post_type=blog&#038;p=6180"},"modified":"2026-08-27T13:17:46","modified_gmt":"2026-08-27T05:17:46","slug":"what-is-a-ul-1077-dc-mcb-standards-tests-and-applications","status":"publish","type":"blog","link":"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications","title":{"rendered":"What Is a UL 1077 DC\u00a0MCB? Standards, Tests, and Applications"},"content":{"rendered":"<p>UL 1077 is a product safety standard for supplementary protectors used in electrical equipment. This standard applies to protective devices installed inside electrical equipment to provide supplementary protection. For manufacturers that need to integrate <a href=\"https:\/\/www.yroele.com\/pt\/dc-circuit-breaker\/\" target=\"_blank\" rel=\"noopener\">DC miniature circuit breakers<\/a> into electrical equipment, UL 1077 is a product standard that requires attention.<\/p>\n<p>This article introduces the scope of UL 1077, the differences between UL 1077 DC MCBs and circuit breakers under other standards, and the main parameters that buyers need to confirm when selecting products.<\/p>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_76 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">\u00cdndice<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Alternar \u00edndice de conte\u00fado\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Alternar<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewbox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewbox=\"0 0 24 24\" version=\"1.2\" baseprofile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#What_Is_UL_1077_Certification\" >What Is UL 1077 Certification?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#What_Does_UL_1077_Test\" >What Does UL 1077 Test?<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#1_Calibration_Test\" >1. Calibration Test<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#2_Overload_Test\" >2. Overload Test<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#3_Endurance_Test\" >3. Endurance Test<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#4_Short-Circuit_Test\" >4. Short-Circuit Test<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#5_Temperature_Rise_Test\" >5. Temperature Rise Test<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#6_Dielectric_Voltage_Withstand_Test\" >6. Dielectric Voltage Withstand Test<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#YRO_DC_Miniature_Circuit_Breaker_Receives_UL_1077_Certification\" >YRO DC Miniature Circuit Breaker Receives UL 1077 Certification<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#Application_Scenarios_for_Circuit_Breakers_With_UL_1077_Certification\" >Application Scenarios for Circuit Breakers With UL 1077 Certification<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#Control_Panels\" >Control Panels<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#Automation_Equipment\" >Automation Equipment<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#New_Energy_Equipment\" >New Energy Equipment<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/www.yroele.com\/pt\/news\/what-is-a-ul-1077-dcmcb-standards-tests-and-applications\/#Conclusion\" >Conclus\u00e3o<\/a><\/li><\/ul><\/nav><\/div>\n<h2><span class=\"ez-toc-section\" id=\"What_Is_UL_1077_Certification\"><\/span><strong>What Is UL 1077 Certification?<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><a href=\"https:\/\/americas.fujielectric.com\/understanding-ul-489-vs-ul-1077-key-differences-and-applications\/\" target=\"_blank\" rel=\"noopener\">UL 1077<\/a> is a safety standard for supplementary protectors used in electrical equipment, published by UL Solutions.<\/p>\n<p>This standard applies to supplementary protectors that provide additional overcurrent protection for electrical equipment. These products are typically installed inside electrical equipment rather than serving as the primary protective devices for building branch circuits.<\/p>\n<p>The UL 1077 standard mainly specifies requirements for supplementary protectors in terms of construction, performance, and testing.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"What_Does_UL_1077_Test\"><\/span><strong>What Does UL 1077 Test?<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"1_Calibration_Test\"><\/span><strong>1. Calibration Test<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The calibration test checks whether the circuit breaker operates according to the specified trip characteristics.<\/p>\n<p>The test applies specified currents to the product and checks whether the product trips within the required time.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"2_Overload_Test\"><\/span><strong>2. Overload Test<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The overload test checks the circuit breaker&#8217;s response under repeated overload conditions.<\/p>\n<p>For DC applications, overload test conditions depend on the product type and specific application requirements. Some DC motor starting applications may use higher test currents.<\/p>\n<p>The overload test includes 50 operating cycles under specified conditions.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"3_Endurance_Test\"><\/span><strong>3. Endurance Test<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The endurance test evaluates the <strong><b>mini <\/b><\/strong><strong><b>circuit breaker&#8217;s<\/b><\/strong>\u00a0performance after repeated operations.<\/p>\n<p>For applicable products, UL 1077 requirements include 6,000 operations at rated current and rated voltage.<\/p>\n<p>This test checks whether the product continues to function properly after completing the specified number of electrical and mechanical operations.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"4_Short-Circuit_Test\"><\/span><strong>4. Short-Circuit Test<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The short-circuit test evaluates the <strong><b>DC MCB&#8217;s<\/b><\/strong>\u00a0performance under specified short-circuit conditions.<\/p>\n<p>The test checks whether the product can interrupt the specified fault current while avoiding unacceptable safety risks.<\/p>\n<p>UL 1077 includes different short-circuit test conditions and categories. Therefore, specific test conditions depend on the product&#8217;s ratings and classification.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"5_Temperature_Rise_Test\"><\/span><strong>5. Temperature Rise Test<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The temperature rise test evaluates the <strong><b>miniature circuit breaker&#8217;s<\/b><\/strong>\u00a0temperature increase under specified operating conditions.<\/p>\n<p>The test checks the temperature changes of relevant current-carrying parts and terminals.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"6_Dielectric_Voltage_Withstand_Test\"><\/span><strong>6. Dielectric Voltage Withstand Test<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The dielectric voltage withstand test evaluates the circuit breaker&#8217;s insulation system.<\/p>\n<p>The test applies specified voltages between relevant electrical parts. The product must meet applicable insulation requirements during the test.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"YRO_DC_Miniature_Circuit_Breaker_Receives_UL_1077_Certification\"><\/span><strong>YRO DC Miniature Circuit Breaker Receives UL 1077 Certification<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>YRO&#8217;s YRL7-125DC series circuit breakers have been evaluated according to the applicable UL 1077 requirements. UL 1077 involves test requirements for calibration, temperature rise, overload, endurance, dielectric voltage withstand, and short-circuit performance.<\/p>\n<p>Different tests evaluate product performance under various conditions. For example, the calibration test checks trip characteristics, the temperature rise test evaluates temperature changes under specified operating conditions, the overload test assesses response under specified overload conditions, and the short-circuit test evaluates interruption performance under specified fault conditions.<\/p>\n<p>For purchasers, certification information can be used to confirm whether the product meets the certification requirements in their equipment design.<\/p>\n<p><img fetchpriority=\"high\" decoding=\"async\" class=\"aligncenter wp-image-6181\" src=\"https:\/\/i1.wp.com\/www.yroele.com\/wp-content\/uploads\/2026\/08\/freecompress-YRL7-125DC-UL1077-\u5df2\u8131\u654f-scaled.jpg?quality=85&strip=all\" alt=\"YRL7-125DC MCB UL1077\" width=\"573\" height=\"800\" srcset=\"https:\/\/i1.wp.com\/www.yroele.com\/wp-content\/uploads\/2026\/08\/freecompress-YRL7-125DC-UL1077-\u5df2\u8131\u654f-scaled.jpg?quality=85&strip=all 1833w, https:\/\/i1.wp.com\/www.yroele.com\/wp-content\/uploads\/2026\/08\/freecompress-YRL7-125DC-UL1077-\u5df2\u8131\u654f-215x300.jpg?quality=85&strip=all 215w, https:\/\/i1.wp.com\/www.yroele.com\/wp-content\/uploads\/2026\/08\/freecompress-YRL7-125DC-UL1077-\u5df2\u8131\u654f-733x1024.jpg?quality=85&strip=all 733w, https:\/\/i1.wp.com\/www.yroele.com\/wp-content\/uploads\/2026\/08\/freecompress-YRL7-125DC-UL1077-\u5df2\u8131\u654f-768x1073.jpg?quality=85&strip=all 768w, https:\/\/i1.wp.com\/www.yroele.com\/wp-content\/uploads\/2026\/08\/freecompress-YRL7-125DC-UL1077-\u5df2\u8131\u654f-1100x1536.jpg?quality=85&strip=all 1100w, https:\/\/i1.wp.com\/www.yroele.com\/wp-content\/uploads\/2026\/08\/freecompress-YRL7-125DC-UL1077-\u5df2\u8131\u654f-1466x2048.jpg?quality=85&strip=all 1466w, https:\/\/i1.wp.com\/www.yroele.com\/wp-content\/uploads\/2026\/08\/freecompress-YRL7-125DC-UL1077-\u5df2\u8131\u654f-9x12.jpg?quality=85&strip=all 9w\" sizes=\"(max-width: 573px) 100vw, 573px\" \/><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Application_Scenarios_for_Circuit_Breakers_With_UL_1077_Certification\"><\/span><strong>Application Scenarios for Circuit Breakers With UL 1077 Certification<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"Control_Panels\"><\/span><strong>Control Panels<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Control panels contain control circuits, power circuits, and other auxiliary circuits. Equipment manufacturers can select DC MCBs that meet UL 1077 requirements,\u00a0for supplementary overcurrent protection of internal circuits within electrical equipment.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Automation_Equipment\"><\/span><strong>Automation Equipment<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Automation equipment contains multiple electrical and electronic components that require circuit protection.<\/p>\n<p>Equipment manufacturers can select <strong><b>MCB<\/b><\/strong><strong><b>\u00a0breaker<\/b><\/strong>\u00a0based on the following parameters:<\/p>\n<ul>\n<li>Tens\u00e3o nominal<\/li>\n<li>Corrente classificada<\/li>\n<li>N\u00famero de p\u00f3los<\/li>\n<li>Trip characteristics<\/li>\n<\/ul>\n<p>The selected protective device needs to match the equipment&#8217;s electrical requirements.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"New_Energy_Equipment\"><\/span><strong>New Energy Equipment<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>New energy equipment contains electrical systems that require circuit protection.<\/p>\n<p>Manufacturers of products such as power conversion equipment can evaluate whether supplementary protection solutions are suitable based on equipment design. The final selection depends on the equipment&#8217;s specific structure and corresponding protection requirements.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Conclusion\"><\/span><strong>Conclus\u00e3o<\/strong><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>UL 1077 certification is mainly used for supplementary protection applications inside electrical equipment.<\/p>\n<p>The UL 1077 standard evaluates supplementary protector performance from multiple aspects, including operating characteristics, temperature rise performance, overload performance, endurance performance, insulation performance, and short-circuit performance.<\/p>\n<p>When <strong><b>purchasing<\/b><\/strong><strong><b>\u00a0electrical<\/b><\/strong><strong><b>\u00a0disjuntores<\/b><\/strong>, buyers need to consider equipment applications, rated voltage, rated current, number of poles, trip characteristics, and applicable certification requirements.<\/p>\n<p>Understanding the application scope of UL 1077 certification,\u00a0can help equipment manufacturers and purchasers select appropriate circuit protection products based on electrical design requirements.<\/p>","protected":false},"excerpt":{"rendered":"<p>This article introduces the scope of UL 1077, the differences between UL 1077 DC MCBs and circuit breakers under other standards, and the main parameters that buyers need to confirm when selecting products.<\/p>","protected":false},"featured_media":6184,"template":"","meta":{"_acf_changed":false,"footnotes":""},"blog_category":[19,20],"class_list":["post-6180","blog","type-blog","status-publish","has-post-thumbnail","hentry","blog_category-news","blog_category-knowledge"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.yroele.com\/pt\/wp-json\/wp\/v2\/blog\/6180","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.yroele.com\/pt\/wp-json\/wp\/v2\/blog"}],"about":[{"href":"https:\/\/www.yroele.com\/pt\/wp-json\/wp\/v2\/types\/blog"}],"version-history":[{"count":2,"href":"https:\/\/www.yroele.com\/pt\/wp-json\/wp\/v2\/blog\/6180\/revisions"}],"predecessor-version":[{"id":6183,"href":"https:\/\/www.yroele.com\/pt\/wp-json\/wp\/v2\/blog\/6180\/revisions\/6183"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.yroele.com\/pt\/wp-json\/wp\/v2\/media\/6184"}],"wp:attachment":[{"href":"https:\/\/www.yroele.com\/pt\/wp-json\/wp\/v2\/media?parent=6180"}],"wp:term":[{"taxonomy":"blog_category","embeddable":true,"href":"https:\/\/www.yroele.com\/pt\/wp-json\/wp\/v2\/blog_category?post=6180"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}