{"id":100057,"date":"2026-02-15T20:09:42","date_gmt":"2026-02-15T20:09:42","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100057"},"modified":"2026-02-15T20:09:42","modified_gmt":"2026-02-15T20:09:42","slug":"circuit-breaker-selection","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/bn\/calculators\/circuit-breaker-selection\/","title":{"rendered":"\u09b8\u09be\u09b0\u09cd\u0995\u09bf\u099f \u09ac\u09cd\u09b0\u09c7\u0995\u09be\u09b0 \u09a8\u09bf\u09b0\u09cd\u09ac\u09be\u099a\u09a8 \u0995\u09cd\u09af\u09be\u09b2\u0995\u09c1\u09b2\u09c7\u099f\u09b0 | MCB\/MCCB \u09b8\u09be\u0987\u099c\u09bf\u0982 | \u09ac\u09bf\u09a8\u09be\u09ae\u09c2\u09b2\u09cd\u09af\u09c7 \u0985\u09a8\u09b2\u09be\u0987\u09a8 \u099f\u09c1\u09b2"},"content":{"rendered":"\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Circuit Breaker Selection Calculator\",\"alternateName\":[\"MCB Sizing Calculator\",\"MCCB Selection Tool\"],\"description\":\"Determine MCB\/MCCB rating, trip curve, and breaking capacity based on load current and short circuit level.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/circuit-breaker-selection\/\",\"applicationCategory\":\"Engineering Calculator\",\"operatingSystem\":\"Any (Web Browser)\",\"offers\":{\"@type\":\"Offer\",\"price\":\"0\",\"priceCurrency\":\"EUR\"},\"creator\":{\"@type\":\"Organization\",\"name\":\"Vibromera\",\"url\":\"https:\/\/vibromera.eu\/\"},\"datePublished\":\"2024-01-01\",\"dateModified\":\"2025-06-01\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true,\"featureList\":[\"Standard breaker ratings\",\"Trip curve B\/C\/D recommendation\",\"Breaking capacity check\",\"Cable coordination\",\"Auto-calculation\"],\"keywords\":\"circuit breaker, MCB, MCCB, trip curve, breaking capacity, IEC 60898\"}\n<\/script>\n\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[\n{\"@type\":\"Question\",\"name\":\"How do I select the right circuit breaker rating?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The breaker rated current must satisfy: I_load \u2264 I_breaker \u2264 I_cable. Select the next standard rating above load current (6, 10, 16, 20, 25, 32, 40, 50, 63 A for MCBs). The breaker must also not exceed the cable's current carrying capacity.\"}},\n{\"@type\":\"Question\",\"name\":\"What is the difference between trip curves B, C, and D?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Trip curves define the instantaneous magnetic trip threshold. B curve: 3-5\u00d7 rated (resistive loads, lighting). C curve: 5-10\u00d7 rated (general loads, small motors). D curve: 10-20\u00d7 rated (motors, transformers with high inrush).\"}},\n{\"@type\":\"Question\",\"name\":\"What is breaking capacity and why does it matter?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Breaking capacity (kA) is the maximum short-circuit current the breaker can safely interrupt. It must exceed the prospective fault current at the installation point. Typical values: 6 kA residential, 10-25 kA commercial, 36-50+ kA industrial.\"}},\n{\"@type\":\"Question\",\"name\":\"What is the difference between MCB and MCCB?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"MCB (Miniature Circuit Breaker): up to 125 A, fixed settings, for branch circuits. MCCB (Moulded Case Circuit Breaker): up to 2500 A, adjustable trip settings, higher breaking capacity, for feeders and main distribution.\"}},\n{\"@type\":\"Question\",\"name\":\"How do I coordinate breakers for selective tripping?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Selectivity (discrimination) ensures only the breaker closest to the fault trips. Rules: upstream breaker should have higher rating, slower trip time, and the ratio of rated currents should typically be \u2265 1.6:1 for MCBs of the same curve type.\"}}\n]}\n<\/script>\n\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"BreadcrumbList\",\"itemListElement\":[\n{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/vibromera.eu\/\"},\n{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Calculators\",\"item\":\"https:\/\/vibromera.eu\/calculators\/\"},\n{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Circuit Breaker Selection\",\"item\":\"https:\/\/vibromera.eu\/calculators\/circuit-breaker-selection\/\"}\n]}\n<\/script>\n\n<link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n\n<link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n\n<link 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print{.vc-section-body{max-height:none!important}.vc-faq-a{max-height:none!important}.vc-results{max-height:none!important;padding:24px!important}.vc-copy-btn,.vc-section-chevron,.vc-faq-chevron,.vc-presets,.vc-promo{display:none!important}}\n<\/style>\n\n<div class=\"vc-calculator\" id=\"vc-circuit-breaker-selection\">\n<header class=\"vc-header\">\n    <p class=\"vc-header-eyebrow\">Free Engineering Tool<\/p>\n    <h1 class=\"vc-header-title\">Circuit Breaker Selection Calculator<\/h1>\n    <p class=\"vc-header-subtitle\">Determine MCB\/MCCB rating, trip curve (B\/C\/D), and verify breaking capacity. Rule: I<sub>load<\/sub> \u2264 I<sub>breaker<\/sub> \u2264 I<sub>cable<\/sub>.<\/p>\n    <div class=\"vc-badges\"><span class=\"vc-badge\">IEC 60898<\/span><span class=\"vc-badge\">IEC 60947<\/span><span class=\"vc-badge\">B \/ C \/ D Curves<\/span><\/div>\n<\/header>\n\n<div class=\"vc-card\">\n    <form class=\"vc-form\" id=\"vc-form\" autocomplete=\"off\">\n        <div class=\"vc-form-grid\">\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-iload\">Design Load Current <span class=\"vc-label-hint\">(A)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-iload\" inputmode=\"decimal\" step=\"any\" min=\"0\" placeholder=\"e.g. 28\" value=\"28\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-icable\">Cable Current Rating <span class=\"vc-label-hint\">(A)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-icable\" inputmode=\"decimal\" step=\"any\" min=\"0\" placeholder=\"e.g. 41\" value=\"41\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-isc\">Prospective Short-Circuit <span class=\"vc-label-hint\">(kA)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-isc\" inputmode=\"decimal\" step=\"any\" min=\"0\" placeholder=\"e.g. 10\" value=\"10\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-loadtype\">Load Type<\/label>\n                <select class=\"vc-select\" id=\"vc-loadtype\">\n                    <option value=\"resistive\">Resistive (lighting, heaters)<\/option>\n                    <option value=\"general\" selected>General (mixed loads)<\/option>\n                    <option value=\"motor\">Motor (high inrush)<\/option>\n                    <option value=\"transformer\">Transformer (very high inrush)<\/option>\n                <\/select>\n            <\/div>\n        <\/div>\n        <div class=\"vc-presets\">\n            <div class=\"vc-presets-label\">Quick presets<\/div>\n            <button type=\"button\" class=\"vc-preset-btn\" data-il=\"12\" data-ic=\"21\" data-isc=\"6\" data-lt=\"resistive\">Lighting 12A \/ 2.5mm\u00b2<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-il=\"28\" data-ic=\"41\" data-isc=\"10\" data-lt=\"general\">Socket ring 28A \/ 4mm\u00b2<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-il=\"50\" data-ic=\"68\" data-isc=\"15\" data-lt=\"motor\">Motor 50A \/ 10mm\u00b2<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-il=\"100\" data-ic=\"130\" data-isc=\"25\" data-lt=\"motor\">Feeder 100A \/ 35mm\u00b2<\/button>\n        <\/div>\n    <\/form>\n\n    <div class=\"vc-results\" id=\"vc-results\">\n        <div class=\"vc-results-head\">\n            <h2 class=\"vc-results-title\">Results<\/h2>\n            <button type=\"button\" class=\"vc-copy-btn\" id=\"vc-copy-btn\"><svg width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><rect x=\"9\" y=\"9\" width=\"13\" height=\"13\" rx=\"2\"\/><path d=\"M5 15H4a2 2 0 01-2-2V4a2 2 0 012-2h9a2 2 0 012 2v1\"\/><\/svg> Copy<\/button>\n        <\/div>\n        <div class=\"vc-result-grid\">\n            <div class=\"vc-rcard vc-rcard-primary\">\n                <div class=\"vc-rcard-label\">Recommended Breaker Rating<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-rating\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Trip Curve<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-curve\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Min Breaking Capacity<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-bkcap\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Breaker Type<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-type\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Coordination Check<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-coord\">\u2014<\/div>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<div class=\"vc-section vc-open\" id=\"vc-sec-theory\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"true\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\ud83d\udcd8<\/span><span class=\"vc-section-title\">Theory &amp; Formulas<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner vc-theory\">\n        <h3>Selection Rule<\/h3>\n        <div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\n        <h3>Trip Curves (IEC 60898)<\/h3>\n        <table class=\"vc-table\">\n            <thead><tr><th>Curve<\/th><th>Magnetic Trip<\/th><th>Application<\/th><\/tr><\/thead>\n            <tbody>\n                <tr><td>B<\/td><td>3\u20135 \u00d7 I<sub>n<\/sub><\/td><td>Resistive loads, long cables<\/td><\/tr>\n                <tr><td>C<\/td><td>5\u201310 \u00d7 I<sub>n<\/sub><\/td><td>General purpose, small motors<\/td><\/tr>\n                <tr><td>D<\/td><td>10\u201320 \u00d7 I<sub>n<\/sub><\/td><td>Motors, transformers, high inrush<\/td><\/tr>\n            <\/tbody>\n        <\/table>\n        <div class=\"vc-warning-box\"><p style=\"margin:0;font-size:14px;color:var(--vc-ink-secondary)\"><strong>\u26a0\ufe0f Note:<\/strong> This tool gives guidance only. Final selection must be verified by a qualified electrical engineer considering all installation conditions.<\/p><\/div>\n    <\/div><\/div>\n<\/div>\n\n<div class=\"vc-section\" id=\"vc-sec-related\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\ud83d\udd17<\/span><span class=\"vc-section-title\">Related Calculators<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-related\">\n        <a class=\"vc-related-link\" href=\"\/calculators\/voltage-drop-calculator\/\">Voltage Drop<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/motor-starting-current\/\">Motor Starting Current<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/three-phase-motor-power\/\">Three-Phase Power<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/grounding-calculator\/\">Grounding<\/a>\n    <\/div><\/div><\/div>\n<\/div>\n\n<div class=\"vc-section\" id=\"vc-sec-faq\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\u2753<\/span><span class=\"vc-section-title\">Frequently Asked Questions<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-faq-list\" id=\"vc-faq-list\"><\/div><\/div><\/div>\n<\/div>\n\n<div class=\"vc-promo\"><div class=\"vc-promo-text\"><strong>Vibromera \u2014 Portable Balancing &amp; Vibration Analysis<\/strong><br>Professional instruments. Used in 50+ countries.<\/div><a class=\"vc-promo-link\" href=\"https:\/\/vibromera.eu\/\" target=\"_blank\" rel=\"noopener\">Learn More<\/a><\/div>\n<footer class=\"vc-footer\"><p>\u00a9 2024\u20132025 <a href=\"https:\/\/vibromera.eu\/\">Vibromera<\/a> \u2014 Engineering Calculators<\/p><p style=\"font-size:12px;margin-top:4px;\">IEC 60898 \/ IEC 60947. Last updated: June 2025<\/p><div class=\"vc-footer-links\"><a href=\"\/calculators\/engineering-calculators\/\">All Calculators<\/a><a href=\"https:\/\/vibromera.eu\/contacts\/\">Contact<\/a><\/div><\/footer>\n<\/div>\n\n<script src=\"https:\/\/cdn.jsdelivr.net\/npm\/katex@0.16.11\/dist\/katex.min.js\"><\/script>\n<script>\n(function(){\n    'use strict';\n    var SLUG='circuit-breaker-selection';\n    function $(id){return document.getElementById(id)}\n    function fmt(n,d){if(isNaN(n)||!isFinite(n))return'\u2014';var f=n.toFixed(d===undefined?2:d);return f.replace(\/(\\.\\d*?)0+$\/,'$1').replace(\/\\.$\/,'')}\n\n    var stdMCB=[6,10,13,16,20,25,32,40,50,63,80,100,125];\n    var stdMCCB=[100,125,160,200,250,315,400,500,630,800,1000,1250,1600];\n    var curveMap={resistive:'B',general:'C',motor:'D',transformer:'D'};\n\n    function nextStd(arr,val){for(var i=0;i<arr.length;i++){if(arr[i]>=val)return arr[i]}return arr[arr.length-1]}\n\n    function calculate(){\n        var Il=parseFloat($('vc-iload').value);\n        var Ic=parseFloat($('vc-icable').value);\n        var Isc=parseFloat($('vc-isc').value);\n        var lt=$('vc-loadtype').value;\n        if(!Il||Il<=0){$('vc-results').classList.remove('vc-visible');return}\n        if(!Ic) Ic=Il*1.5;\n        if(!Isc) Isc=6;\n\n        var isMCCB=Il>100;\n        var arr=isMCCB?stdMCCB:stdMCB;\n        var Ib=nextStd(arr,Il);\n        var curve=curveMap[lt]||'C';\n        var ok=Ib<=Ic;\n        var bkOk=true;\n        var bkNeeded=Isc;\n        var typeStr=isMCCB?'MCCB':'MCB';\n        if(Ib>125) typeStr='MCCB';\n\n        $('vc-r-rating').innerHTML=Ib+' <span class=\"vc-rcard-unit\">A '+typeStr+'<\/span>';\n        $('vc-r-curve').innerHTML='Curve '+curve+' <span class=\"vc-rcard-unit\">('+{B:'3-5\u00d7',C:'5-10\u00d7',D:'10-20\u00d7'}[curve]+')<\/span>';\n        $('vc-r-bkcap').innerHTML='\u2265 '+fmt(bkNeeded,0)+' <span class=\"vc-rcard-unit\">kA<\/span>';\n        $('vc-r-type').innerHTML=typeStr;\n        $('vc-r-coord').innerHTML=ok?'<span style=\"color:var(--vc-green)\">\u2713 OK<\/span> <span class=\"vc-rcard-unit\">'+Il+'A \u2264 '+Ib+'A \u2264 '+Ic+'A<\/span>':'<span style=\"color:var(--vc-red)\">\u2717 FAIL<\/span> <span class=\"vc-rcard-unit\">Breaker '+Ib+'A > Cable '+Ic+'A<\/span>';\n        $('vc-results').classList.add('vc-visible');\n\n        var u=new URL(window.location);u.searchParams.set('Il',Il);u.searchParams.set('Ic',Ic);u.searchParams.set('Isc',Isc);u.searchParams.set('lt',lt);history.replaceState(null,'',u.toString());\n        saveHistory({Il:Il,Ib:Ib,curve:curve,_summary:Il+'A \u2192 '+Ib+'A '+curve+' '+typeStr});\n    }\n\n    document.querySelectorAll('.vc-preset-btn').forEach(function(btn){btn.addEventListener('click',function(e){\n        e.preventDefault();$('vc-iload').value=this.getAttribute('data-il');$('vc-icable').value=this.getAttribute('data-ic');$('vc-isc').value=this.getAttribute('data-isc');$('vc-loadtype').value=this.getAttribute('data-lt');calculate();\n    })});\n    $('vc-form').addEventListener('input',calculate);\n    $('vc-form').addEventListener('change',calculate);\n\n    $('vc-copy-btn').addEventListener('click',function(){\n        var text='Circuit Breaker Selection\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\nRating: '+$('vc-r-rating').textContent+'\\nCurve: '+$('vc-r-curve').textContent+'\\nBreaking: '+$('vc-r-bkcap').textContent+'\\nCheck: '+$('vc-r-coord').textContent+'\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\nvibromera.eu';\n        if(navigator.clipboard){navigator.clipboard.writeText(text).then(function(){var b=$('vc-copy-btn');b.classList.add('vc-copied');b.innerHTML='<svg width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><polyline points=\"20 6 9 17 4 12\"\/><\/svg> Copied!';setTimeout(function(){b.classList.remove('vc-copied');b.innerHTML='<svg width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><rect x=\"9\" y=\"9\" width=\"13\" height=\"13\" rx=\"2\"\/><path d=\"M5 15H4a2 2 0 01-2-2V4a2 2 0 012-2h9a2 2 0 012 2v1\"\/><\/svg> Copy'},2000)})}\n    });\n\n    document.querySelectorAll('.vc-section-toggle').forEach(function(btn){btn.addEventListener('click',function(){var s=this.closest('.vc-section');s.classList.toggle('vc-open');this.setAttribute('aria-expanded',s.classList.contains('vc-open'))})});\n\n    var faqData=[\n        {q:'How do I select the right circuit breaker rating?',a:'<p>Rule: I<sub>load<\/sub> \u2264 I<sub>breaker<\/sub> \u2264 I<sub>cable<\/sub>. Pick the next standard rating above load current. Standard MCB: 6, 10, 16, 20, 25, 32, 40, 50, 63A.<\/p>'},\n        {q:'What is the difference between trip curves B, C, and D?',a:'<p>B: 3\u20135\u00d7 (resistive, long cables). C: 5\u201310\u00d7 (general, small motors). D: 10\u201320\u00d7 (motors, transformers with high inrush).<\/p>'},\n        {q:'What is breaking capacity?',a:'<p>Max short-circuit current the breaker can interrupt safely. Must exceed prospective fault level. Typical: 6 kA residential, 10\u201325 kA commercial, 36\u201350 kA industrial.<\/p>'},\n        {q:'MCB vs MCCB \u2014 what is the difference?',a:'<p>MCB: up to 125A, fixed settings, branch circuits. MCCB: up to 2500A, adjustable trip, higher breaking capacity, for feeders.<\/p>'},\n        {q:'How do I ensure selective tripping?',a:'<p>Upstream breaker must have higher rating, slower trip. Current ratio \u22651.6:1 for same curve type MCBs.<\/p>'}\n    ];\n    var fl=$('vc-faq-list');faqData.forEach(function(f){fl.innerHTML+='<div class=\"vc-faq-item\"><button type=\"button\" class=\"vc-faq-q\"><span>'+f.q+'<\/span><svg class=\"vc-faq-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button><div class=\"vc-faq-a\"><div class=\"vc-faq-a-inner\">'+f.a+'<\/div><\/div><\/div>'});\n    fl.addEventListener('click',function(e){var b=e.target.closest('.vc-faq-q');if(b)b.closest('.vc-faq-item').classList.toggle('vc-open')});\n\n    function saveHistory(e){var k='vc_history_'+SLUG;var a=[];try{a=JSON.parse(localStorage.getItem(k))||[]}catch(x){}e._ts=new Date().toISOString();a.unshift(e);if(a.length>10)a=a.slice(0,10);try{localStorage.setItem(k,JSON.stringify(a))}catch(x){}}\n    function loadParams(){var p=new URLSearchParams(window.location.search);p.forEach(function(v,k){var el=$(k)||$('vc-'+k);if(el)el.value=v})}\n    function renderFormulas(){try{katex.render('I_{load} \\\\leq I_{breaker} \\\\leq I_{cable}',$('vc-katex-1'),{displayMode:true,throwOnError:false})}catch(e){}}\n    function init(){loadParams();renderFormulas();calculate()}\n    if(document.readyState==='loading'){document.addEventListener('DOMContentLoaded',init)}else{init()}\n})();\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>\u09ac\u09bf\u09a8\u09be\u09ae\u09c2\u09b2\u09cd\u09af\u09c7 \u0985\u09a8\u09b2\u09be\u0987\u09a8 \u09b8\u09be\u09b0\u09cd\u0995\u09bf\u099f \u09ac\u09cd\u09b0\u09c7\u0995\u09be\u09b0 \u09a8\u09bf\u09b0\u09cd\u09ac\u09be\u099a\u09a8 \u0995\u09cd\u09af\u09be\u09b2\u0995\u09c1\u09b2\u09c7\u099f\u09b0\u0964 \u09b2\u09cb\u09a1 \u09ac\u09b0\u09cd\u09a4\u09ae\u09be\u09a8, \u0995\u09c7\u09ac\u09b2 \u09b0\u09c7\u099f\u09bf\u0982 \u098f\u09ac\u0982 \u09b6\u09b0\u09cd\u099f \u09b8\u09be\u09b0\u09cd\u0995\u09bf\u099f \u09b8\u09cd\u09a4\u09b0\u09c7\u09b0 \u0989\u09aa\u09b0 \u09ad\u09bf\u09a4\u09cd\u09a4\u09bf \u0995\u09b0\u09c7 MCB\/MCCB \u09b0\u09c7\u099f\u09bf\u0982, \u099f\u09cd\u09b0\u09bf\u09aa \u0995\u09be\u09b0\u09cd\u09ad (B\/C\/D), \u098f\u09ac\u0982 \u09ad\u09be\u0999\u09be\u09b0 \u0995\u09cd\u09b7\u09ae\u09a4\u09be \u09a8\u09bf\u09b0\u09cd\u09a7\u09be\u09b0\u09a3 \u0995\u09b0\u09c1\u09a8\u0964<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100057","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100057","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":1,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100057\/revisions"}],"predecessor-version":[{"id":100367,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100057\/revisions\/100367"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/media?parent=100057"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/categories?post=100057"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/tags?post=100057"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}