{"id":3352,"date":"2026-08-04T17:00:00","date_gmt":"2026-08-04T17:00:00","guid":{"rendered":"https:\/\/chac-electric.com\/?p=3352"},"modified":"2026-08-04T18:18:15","modified_gmt":"2026-08-04T18:18:15","slug":"single-pole-vs-double-pole-mcb-selection","status":"publish","type":"post","link":"https:\/\/chac-electric.com\/ar\/blog\/single-pole-vs-double-pole-mcb-selection\/","title":{"rendered":"When Should Panel Builders Use a Single-Pole or Double-Pole MCB?"},"content":{"rendered":"<div class=\"b2b-article\">\n<p style=\"margin:0 0 16px;line-height:1.7\"><strong>For panel builders, the choice between a single-pole and double-pole MCB starts with the conductors the circuit must disconnect and protect\u2014not with panel width or a familiar label.<\/strong> A 1P device addresses one pole; a 2P device has two linked poles. Check whether the selected product switches, protects, or both switches and protects each conductor, then confirm the circuit arrangement, local rules, and product documentation before release.<\/p>\n<figure style=\"margin:26px 0;text-align:center\"><img decoding=\"async\" style=\"max-width:640px;width:100%;height:auto;display:block;margin:0 auto;border-radius:8px\" alt=\"Single-pole CQB2-63 MCB for a panel-builder pole-selection review\" src=\"https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/cqb2-63-series-miniature-circuit-breakers-for-power-systems-cqb2-63.webp\" \/><\/figure>\n<nav class=\"b2b-toc\" style=\"background:#f5f8fa;padding:16px 20px;border-radius:8px;margin:0 0 24px\">\n<h2 id=\"contents\" style=\"margin:42px 0 14px;scroll-margin-top:96px\">\u0645\u062d\u062a\u0648\u064a\u0627\u062a<\/h2>\n<ul style=\"margin:0 0 18px 1.2em;line-height:1.7\">\n<li style=\"margin:0 0 8px\"><a href=\"#part-1-start-with-the-conductors-the-circuit-must-disconnect\">Part 1. Start With the Conductors the Circuit Must Disconnect<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-2-what-a-single-pole-mcb-does-and-does-not-do\">Part 2. What a Single-Pole MCB Does\u2014and Does Not Do<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-3-why-1p-n-needs-its-own-check\">Part 3. Why 1P+N Needs Its Own Check<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-4-when-a-double-pole-mcb-belongs-in-the-review\">Part 4. When a Double-Pole MCB Belongs in the Review<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-5-turn-the-comparison-into-a-panel-decision\">Part 5. Turn the Comparison Into a Panel Decision<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-6-choose-a-product-route-only-after-the-inputs-are-defined\">Part 6. Choose a Product Route Only After the Inputs Are Defined<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-7-fit-boundary-when-the-pole-count-is-not-the-final-decision\">Part 7. Fit Boundary: When the Pole Count Is Not the Final Decision<\/a><\/li>\n<\/ul>\n<\/nav>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-1-start-with-the-conductors-the-circuit-must-disconnect\">Part 1. Start With the Conductors the Circuit Must Disconnect<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">Pole count describes a device arrangement; it does not, by itself, confirm how a particular installation should be protected. Begin with the single-line diagram and identify every conductor that must open together for the circuit&#8217;s required switching or isolation function.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">The next check is separate: identify which conductors require overcurrent protection. A product label, a catalogue filter, and a visual comparison do not replace the selected model&#8217;s wiring diagram, markings, and technical documentation.<\/p>\n<table style=\"width:100%;border-collapse:collapse\">\n<thead>\n<tr>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Review question<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Why it changes the choice<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Evidence to keep with the panel file<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Which conductors supply the load?<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Defines whether the circuit has one or two conductors to be opened together<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Single-line diagram and circuit designation<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Which conductors must be switched?<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Separates switching needs from overcurrent-protection needs<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Applicable project rule and device diagram<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Which poles are protected?<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Prevents treating every two-pole construction as identical<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Selected model datasheet and marking<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Is the duty AC or DC?<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">AC suitability does not establish DC suitability<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Rated-duty documentation for the exact device<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style=\"margin:0 0 16px;line-height:1.7\">For a wider view of terms such as poles, curves, and markings, use this <a href=\"https:\/\/chac-electric.com\/ar\/%d9%85%d8%af%d9%88%d9%86%d8%a9\/miniature-circuit-breaker-types-specifications-complete-guide-to-selection-working-principle-and-applications\/\">MCB types and specifications guide<\/a> alongside the final product documentation.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-2-what-a-single-pole-mcb-does-and-does-not-do\">Part 2. What a Single-Pole MCB Does\u2014and Does Not Do<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">A single-pole MCB is intended to switch and protect one conductor in the circuit arrangement for which it is specified. That can be an appropriate starting point when the circuit design, applicable rules, and selected device documentation all support a one-pole arrangement.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">The limitation is equally important: one-pole switching does not become two-conductor isolation because a nearby neutral or another conductor is present. The panel drawing must show what remains connected when the device is open.<\/p>\n<table style=\"width:100%;border-collapse:collapse\">\n<thead>\n<tr>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Single-pole review point<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">What to confirm before selection<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Circuit arrangement<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">The conductor assigned to the pole and the intended circuit function<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Switching expectation<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Whether opening one conductor satisfies the documented isolation approach<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Protection expectation<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">The pole&#8217;s overcurrent function as stated in the selected documentation<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Panel interface<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Mounting, terminals, accessories, and labelling in the actual assembly<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style=\"margin:0 0 16px;line-height:1.7\">This comparison does not prescribe a universal application list. A panel builder should document the circuit role first, then compare the request with the applicable installation rules and the selected MCB instructions.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-3-why-1p-n-needs-its-own-check\">Part 3. Why 1P+N Needs Its Own Check<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">The label 1P+N deserves a separate line in the bill of materials. It is commonly used for a construction that switches line and neutral together while the overcurrent function is associated with the line pole; however, the exact arrangement is a selected-product question, not a shorthand that can be assumed from the label alone.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">That distinction matters because 1P+N and 2P may meet different switching and protection requirements. Ask the supplier for the device diagram, pole function, applicable standard, and intended supply arrangement before substituting one for the other.<\/p>\n<figure style=\"margin:26px 0;text-align:center\"><img decoding=\"async\" style=\"max-width:640px;width:100%;height:auto;display:block;margin:0 auto;border-radius:8px\" alt=\"Two-pole CQB2-63 MCB shown as a product construction reference\" src=\"https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/cqb2-63-series-miniature-circuit-breakers-for-power-systems-cqb2-63-2.webp\" \/><\/figure>\n<blockquote>\n<p style=\"margin:0 0 16px;line-height:1.7\"><strong>Important:<\/strong> Do not use an AC MCB on a DC circuit merely because it has one or two poles. IEC 60898-2 gives additional requirements for single- and two-pole breakers suitable for AC and DC operation; the exact product must be explicitly rated and documented for the intended duty. (<a href=\"https:\/\/webstore.iec.ch\/en\/publication\/25675\" rel=\"nofollow noopener\" target=\"_blank\">IEC 60898-2:2016<\/a>)<\/p>\n<\/blockquote>\n<p style=\"margin:0 0 16px;line-height:1.7\">Use the <a href=\"https:\/\/chac-electric.com\/ar\/%d9%85%d8%af%d9%88%d9%86%d8%a9\/decoding-the-mcb-nameplate-a-guide-to-key-specifications-for-safer-electrical-system-design\/\">MCB nameplate guide<\/a> to prepare questions, but use the selected product documentation to make the final determination.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-4-when-a-double-pole-mcb-belongs-in-the-review\">Part 4. When a Double-Pole MCB Belongs in the Review<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">A double-pole MCB is relevant when the circuit requires two conductors to be opened together or requires the two-pole construction documented by the project. The two poles are mechanically linked, but their protected-pole arrangement still needs confirmation from the exact device documentation.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Consider the review prompt rather than a blanket rule:<\/p>\n<ul style=\"margin:0 0 18px 1.2em;line-height:1.7\">\n<li style=\"margin:0 0 8px\">Does the circuit contain two conductors that must disconnect together?<\/li>\n<li style=\"margin:0 0 8px\">Does the project documentation call for simultaneous disconnection or a specific pole arrangement?<\/li>\n<li style=\"margin:0 0 8px\">Does the selected product state how each pole is switched and protected?<\/li>\n<li style=\"margin:0 0 8px\">Do the device&#8217;s rated duty, standard, and installation conditions match the project requirement?<\/li>\n<\/ul>\n<p style=\"margin:0 0 16px;line-height:1.7\">IEC 60898-1 provides the product-standard context for AC breakers in household and similar installations within its defined scope. Projects for instructed or skilled persons can require a different standard context, so the project specification\u2014not the article title\u2014determines what is applicable.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-5-turn-the-comparison-into-a-panel-decision\">Part 5. Turn the Comparison Into a Panel Decision<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">Translate the pole question into a documented selection path. The table below keeps switching, protection, and procurement evidence separate so that a quote cannot quietly replace a circuit decision.<\/p>\n<table style=\"width:100%;border-collapse:collapse\">\n<thead>\n<tr>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Decision point<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">1P review<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">2P review<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Send with RFQ<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Circuit conductors<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Identify the one conductor assigned to the MCB pole<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Identify both conductors and why they must open together<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Single-line diagram and circuit identifier<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Switching function<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Confirm that one-pole opening matches the documented design<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Confirm simultaneous two-pole opening is required<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Required operating and isolation function<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Pole protection<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Verify the protected-pole function from the selected model<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Verify each pole&#8217;s protected-pole function from the selected model<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Datasheet, wiring diagram, and model code<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Duty and standard<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Confirm the selected device&#8217;s documented application<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Confirm the selected device&#8217;s documented application<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">AC\/DC duty, applicable standard, target-market requirement<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Assembly constraints<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Check the actual panel layout and interfaces<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Check the actual panel layout and interfaces<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Mounting detail, accessories, labelling, and quantity<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style=\"margin:0 0 16px;line-height:1.7\">This approach also prevents a common sourcing error: comparing only current rating and pole count while omitting the circuit diagram and required documentation. The final choice must be based on the circuit, load, local rules, and the selected product file.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-6-choose-a-product-route-only-after-the-inputs-are-defined\">Part 6. Choose a Product Route Only After the Inputs Are Defined<\/h2>\n<h3 style=\"margin:28px 0 12px\">\u062a\u0648\u0635\u064a\u0629 \u0628\u0627\u0644\u0645\u0646\u062a\u062c<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">Once the project inputs are complete, the published <a href=\"https:\/\/chac-electric.com\/ar\/product\/cqb2-63-miniature-circuit-breaker\/\">CQB2-63 MCB family<\/a> is a relevant first-party route to discuss because its page lists 1P, 1P+N, and 2P family options. It is not a statement that any option on that page fits a particular panel.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">For category context, review CHAC Electric&#8217;s <a href=\"https:\/\/chac-electric.com\/ar\/mcb\/\">MCB product category<\/a> and the broader <a href=\"https:\/\/chac-electric.com\/ar\/%d8%a7%d9%84%d8%a3%d8%ac%d9%87%d8%b2%d8%a9-%d8%a7%d9%84%d9%83%d9%87%d8%b1%d8%a8%d8%a7%d8%a6%d9%8a%d8%a9-%d8%a7%d9%84%d8%b7%d8%b1%d9%81%d9%8a%d8%a9\/\">\u0627\u0644\u0623\u062c\u0647\u0632\u0629 \u0627\u0644\u0643\u0647\u0631\u0628\u0627\u0626\u064a\u0629 \u0627\u0644\u0637\u0631\u0641\u064a\u0629<\/a> range. Do not choose a generic substitute solely because it looks similar or has the same number of poles; the required protected-pole arrangement, rated duty, standard, and panel fit must all be verified.<\/p>\n<figure style=\"margin:26px 0;text-align:center\"><img decoding=\"async\" style=\"max-width:640px;width:100%;height:auto;display:block;margin:0 auto;border-radius:8px\" alt=\"Two-pole CQB2-125 MCB used as a first-party product-route reference\" src=\"https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/cqb2-63-series-miniature-circuit-breakers-for-power-systems-cqb2-125-2p-20200328.webp\" \/><\/figure>\n<p style=\"margin:0 0 16px;line-height:1.7\">For an OEM discussion, send the single-line diagram, conductor arrangement, intended duty, documentation requirement, panel constraints, and branding or packaging needs through <a href=\"https:\/\/chac-electric.com\/ar\/%d8%aa%d8%ae%d8%b5%d9%8a%d8%b5-%d8%a7%d9%84%d9%85%d9%86%d8%aa%d8%ac%d8%a7%d8%aa-%d8%a7%d9%84%d9%83%d9%87%d8%b1%d8%a8%d8%a7%d8%a6%d9%8a%d8%a9-%d8%a7%d9%84%d8%b7%d8%b1%d9%81%d9%8a%d8%a9\/\">terminal electrical product customization<\/a>. That gives the supplier a reviewable basis for a product-route discussion.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-7-fit-boundary-when-the-pole-count-is-not-the-final-decision\">Part 7. Fit Boundary: When the Pole Count Is Not the Final Decision<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">Fit Boundary: this guide is useful for early comparison, panel specification, and supplier communication. It is not suitable for live-work instructions, final protection coordination, a local-code interpretation, or a DC selection without an explicit rating for the intended DC duty.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Pole count is only one field in a release decision. The final selection must be checked against the circuit and load, local regulations, the panel design, the applicable standard, and the selected product&#8217;s current documentation.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">When the drawing and requirement set are ready, <a href=\"https:\/\/chac-electric.com\/ar\/%d8%a7%d8%aa%d8%b5%d9%84-%d8%a8%d9%86%d8%a7\/\">\u0627\u062a\u0635\u0644 \u0628\u0640 CHAC Electric<\/a> with the required pole arrangement and evidence package for a product discussion.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"faqs\">\u0627\u0644\u0623\u0633\u0626\u0644\u0629 \u0627\u0644\u0645\u062a\u0643\u0631\u0631\u0629<\/h2>\n<h3 style=\"margin:28px 0 12px\">What is the basic difference between a 1P and a 2P MCB?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">A 1P MCB has one pole for the conductor assigned to it. A 2P MCB has two mechanically linked poles that open together. The selected product documentation must still confirm the function and protection arrangement of each pole.<\/p>\n<h3 style=\"margin:28px 0 12px\">Is 1P+N the same as 2P?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">No. A 1P+N label is commonly associated with line-and-neutral switching with overcurrent protection on the line pole, while a 2P device may have a different protected-pole arrangement. Confirm both the wiring diagram and product markings before treating them as alternatives.<\/p>\n<h3 style=\"margin:28px 0 12px\">Does a 2P label prove that both poles are protected?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">No. Pole count alone does not establish how each pole is protected. Request the selected model&#8217;s datasheet and wiring information, then compare them with the circuit requirement.<\/p>\n<h3 style=\"margin:28px 0 12px\">Can an AC MCB be used on a DC circuit?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">Only when the exact device is explicitly rated and documented for the intended DC duty. IEC 60898-2 addresses additional requirements for eligible single- and two-pole AC\/DC breakers, but it does not make every AC MCB suitable for DC.<\/p>\n<h3 style=\"margin:28px 0 12px\">Which standards should a panel builder review for an MCB request?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">Start with the standard and installation rule named in the project documents. IEC 60898-1 covers AC breakers for household and similar installations within its scope, while IEC 60947-2 is a low-voltage circuit-breaker standard context for instructed or skilled persons. The project requirement and selected-model documents determine the final basis.<\/p>\n<h3 style=\"margin:28px 0 12px\">What should be included in an MCB RFQ?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">Include the single-line diagram, supply and circuit arrangement, conductors to be switched, protected-pole expectation, AC or DC duty, applicable standard, selected-model evidence required, panel constraints, and any branding or packaging request.<\/p>\n<h3 style=\"margin:28px 0 12px\">When is this guide not enough for final selection?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">It is not enough when the project requires final coordination, local-code interpretation, live-work guidance, or a model-specific approval. Those decisions require the actual circuit and load information, local rules, and the selected product documentation.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"references\">\u0627\u0644\u0645\u0631\u0627\u062c\u0639<\/h2>\n<ul style=\"margin:0 0 18px 1.2em;line-height:1.7\">\n<li style=\"margin:0 0 8px\"><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/66269\" rel=\"nofollow noopener\" target=\"_blank\">IEC 60898-1:2015+AMD1:2019 \u2014 circuit-breakers for household and similar AC installations<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/25675\" rel=\"nofollow noopener\" target=\"_blank\">IEC 60898-2:2016 \u2014 additional requirements for eligible single- and two-pole AC\/DC circuit-breakers<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/66277\" rel=\"nofollow noopener\" target=\"_blank\">IEC 60947-2:2024 \u2014 low-voltage circuit-breakers<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"https:\/\/electronics.stackexchange.com\/questions\/392871\/when-to-use-a-2-pole-circuit-breaker-over-1-pole\" rel=\"nofollow noopener\" target=\"_blank\">Electronics Stack Exchange discussion of 1P, 1P+N, and isolation questions<\/a><\/li>\n<\/ul>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>For panel builders, the choice between a single-pole and double-pole MCB starts with the conductors the circuit must disconnect and protect\u2014not with panel width or a familiar label. A 1P device addresses one pole; a 2P device has two linked poles. Check whether the selected product switches, protects, or both switches and protects each conductor, [&hellip;]<\/p>\n","protected":false},"author":10,"featured_media":3119,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-3352","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"blocksy_meta":[],"acf":[],"_links":{"self":[{"href":"https:\/\/chac-electric.com\/ar\/wp-json\/wp\/v2\/posts\/3352","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/chac-electric.com\/ar\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/chac-electric.com\/ar\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/chac-electric.com\/ar\/wp-json\/wp\/v2\/users\/10"}],"replies":[{"embeddable":true,"href":"https:\/\/chac-electric.com\/ar\/wp-json\/wp\/v2\/comments?post=3352"}],"version-history":[{"count":1,"href":"https:\/\/chac-electric.com\/ar\/wp-json\/wp\/v2\/posts\/3352\/revisions"}],"predecessor-version":[{"id":3353,"href":"https:\/\/chac-electric.com\/ar\/wp-json\/wp\/v2\/posts\/3352\/revisions\/3353"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/chac-electric.com\/ar\/wp-json\/wp\/v2\/media\/3119"}],"wp:attachment":[{"href":"https:\/\/chac-electric.com\/ar\/wp-json\/wp\/v2\/media?parent=3352"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/chac-electric.com\/ar\/wp-json\/wp\/v2\/categories?post=3352"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/chac-electric.com\/ar\/wp-json\/wp\/v2\/tags?post=3352"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}