{"id":100162,"date":"2026-02-15T20:21:47","date_gmt":"2026-02-15T20:21:47","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100162"},"modified":"2026-04-05T15:39:45","modified_gmt":"2026-04-05T15:39:45","slug":"motor-starting-current","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/bn\/calculators\/motor-starting-current\/","title":{"rendered":"\u09ae\u09cb\u099f\u09b0 \u09b8\u09cd\u099f\u09be\u09b0\u09cd\u099f\u09bf\u0982 \u0995\u09be\u09b0\u09c7\u09a8\u09cd\u099f \u0995\u09cd\u09af\u09be\u09b2\u0995\u09c1\u09b2\u09c7\u099f\u09b0 | \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\":\"Motor Starting Current Calculator\",\"alternateName\":[\"Inrush Current Calculator\",\"Locked Rotor Current Calculator\"],\"description\":\"Calculate motor starting (inrush) current for DOL, star-delta, soft starter, and VFD starting methods.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/motor-starting-current\/\",\"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\":[\"DOL starting 6-8\u00d7\",\"Star-delta starting 2-3\u00d7\",\"VFD starting 1-1.5\u00d7\",\"Auto-calculation\",\"Presets for common motors\"],\"keywords\":\"motor starting current, inrush current, DOL, star-delta, VFD\"}\n<\/script>\n\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[\n{\"@type\":\"Question\",\"name\":\"What is motor starting current?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Motor starting current (inrush current) is the initial surge of current when a motor is first energized. For DOL (direct-on-line) starting, it is typically 6\u20138 times the rated full-load current and lasts until the motor reaches operating speed.\"}},\n{\"@type\":\"Question\",\"name\":\"Why is starting current so high?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"At standstill, the rotor does not generate back-EMF, so the motor winding impedance is very low, resulting in high current. As the motor accelerates, back-EMF builds up and current drops to the normal running value.\"}},\n{\"@type\":\"Question\",\"name\":\"What is the difference between DOL and star-delta starting?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"DOL (direct-on-line) applies full voltage immediately, giving 6-8\u00d7 rated current. Star-delta starts in star connection (1\/3 voltage per winding), reducing starting current to about 1\/3 of DOL values (2-3\u00d7 rated), then switches to delta for normal running.\"}},\n{\"@type\":\"Question\",\"name\":\"How does a VFD reduce starting current?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"A Variable Frequency Drive (VFD) controls both voltage and frequency, ramping them up gradually. This allows the motor to start with only 1\u20131.5\u00d7 rated current while still providing adequate starting torque.\"}},\n{\"@type\":\"Question\",\"name\":\"What is the NEMA code letter for locked rotor current?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"NEMA code letters (A through V) indicate the locked rotor kVA per HP. For example, code letter F means 5.0\u20135.6 kVA\/HP. The starting current can be calculated as I_start = (kVA\/HP \u00d7 HP \u00d7 1000) \/ (\u221a3 \u00d7 V).\"}}\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\":\"Motor Starting Current\",\"item\":\"https:\/\/vibromera.eu\/calculators\/motor-starting-current\/\"}\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-motor-starting-current\">\n\n<header class=\"vc-header\">\n    <p class=\"vc-header-eyebrow\">Free Engineering Tool<\/p>\n    <h1 class=\"vc-header-title\">Motor Starting Current Calculator<\/h1>\n    <p class=\"vc-header-subtitle\">Calculate motor starting (inrush) current for DOL, star-delta, soft starter, and VFD methods. I<sub>start<\/sub> = k<sub>start<\/sub> \u00d7 I<sub>rated<\/sub>.<\/p>\n    <div class=\"vc-badges\">\n        <span class=\"vc-badge\">DOL 6\u20138\u00d7<\/span>\n        <span class=\"vc-badge\">Star-Delta 2\u20133\u00d7<\/span>\n        <span class=\"vc-badge\">VFD 1\u20131.5\u00d7<\/span>\n    <\/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-power\">Rated Motor Power <span class=\"vc-label-hint\">(kW)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-power\" inputmode=\"decimal\" step=\"any\" min=\"0\" placeholder=\"e.g. 15\" value=\"15\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-voltage\">Line Voltage <span class=\"vc-label-hint\">(V)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-voltage\" inputmode=\"decimal\" step=\"any\" min=\"0\" placeholder=\"e.g. 400\" value=\"400\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-pf\">Power Factor cos \u03c6 <span class=\"vc-label-hint\">(0\u20131)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-pf\" inputmode=\"decimal\" step=\"0.01\" min=\"0\" max=\"1\" placeholder=\"e.g. 0.85\" value=\"0.85\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-eff\">Efficiency \u03b7 <span class=\"vc-label-hint\">(0\u20131)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-eff\" inputmode=\"decimal\" step=\"0.01\" min=\"0\" max=\"1\" placeholder=\"e.g. 0.91\" value=\"0.91\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-method\">Starting Method<\/label>\n                <select class=\"vc-select\" id=\"vc-method\">\n                    <option value=\"dol\">DOL (Direct On Line) \u2014 6\u20138\u00d7<\/option>\n                    <option value=\"stardelta\">Star-Delta (Y-\u0394) \u2014 2\u20133\u00d7<\/option>\n                    <option value=\"softstarter\">Soft Starter \u2014 2\u20134\u00d7<\/option>\n                    <option value=\"vfd\">VFD \/ Inverter \u2014 1\u20131.5\u00d7<\/option>\n                <\/select>\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-kmult\">Start Multiplier k <span class=\"vc-label-hint\" id=\"vc-kmult-hint\">(\u00d7I_rated)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-kmult\" inputmode=\"decimal\" step=\"0.1\" min=\"0\" placeholder=\"e.g. 7\" value=\"7\">\n            <\/div>\n        <\/div>\n\n        <div class=\"vc-presets\">\n            <div class=\"vc-presets-label\">Quick presets<\/div>\n            <button type=\"button\" class=\"vc-preset-btn\" data-p=\"7.5\" data-v=\"400\" data-pf=\"0.84\" data-eff=\"0.89\" data-m=\"dol\" data-k=\"7\">7.5 kW DOL<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-p=\"15\" data-v=\"400\" data-pf=\"0.85\" data-eff=\"0.91\" data-m=\"stardelta\" data-k=\"2.5\">15 kW Star-Delta<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-p=\"37\" data-v=\"400\" data-pf=\"0.86\" data-eff=\"0.93\" data-m=\"softstarter\" data-k=\"3\">37 kW Soft Start<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-p=\"75\" data-v=\"400\" data-pf=\"0.87\" data-eff=\"0.95\" data-m=\"vfd\" data-k=\"1.2\">75 kW VFD<\/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\">\n                <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>\n                Copy\n            <\/button>\n        <\/div>\n        <div class=\"vc-result-grid\">\n            <div class=\"vc-rcard vc-rcard-primary\">\n                <div class=\"vc-rcard-label\">Starting Current I_start<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-istart\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Rated Full-Load Current I_rated<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-irated\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Start Multiplier k<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-kmult\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Starting Apparent Power<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-sstart\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Starting Method<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-method\">\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\">\n        <span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\ud83d\udcd8<\/span><span class=\"vc-section-title\">Theory &amp; Formulas<\/span><\/span>\n        <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>\n    <\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner vc-theory\">\n            <h3>Rated Current<\/h3>\n            <div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\n            <h3>Starting Current<\/h3>\n            <div class=\"vc-formula-box\" id=\"vc-katex-2\"><\/div>\n            <h3>Starting Methods Comparison<\/h3>\n            <table class=\"vc-table\">\n                <thead><tr><th>Method<\/th><th>Current Multiplier<\/th><th>Torque<\/th><th>Typical Use<\/th><\/tr><\/thead>\n                <tbody>\n                    <tr><td>DOL<\/td><td>6\u20138 \u00d7 I<sub>rated<\/sub><\/td><td>Full<\/td><td>Small motors &lt; 7.5 kW<\/td><\/tr>\n                    <tr><td>Star-Delta<\/td><td>2\u20133 \u00d7 I<sub>rated<\/sub><\/td><td>~33%<\/td><td>Pumps, fans, 7.5\u201375 kW<\/td><\/tr>\n                    <tr><td>Soft Starter<\/td><td>2\u20134 \u00d7 I<sub>rated<\/sub><\/td><td>Variable<\/td><td>Conveyors, compressors<\/td><\/tr>\n                    <tr><td>VFD<\/td><td>1\u20131.5 \u00d7 I<sub>rated<\/sub><\/td><td>Full<\/td><td>Any, best control<\/td><\/tr>\n                <\/tbody>\n            <\/table>\n            <div class=\"vc-example-box\">\n                <div class=\"vc-example-title\">Example \u2014 15 kW Motor, DOL Start<\/div>\n                <p><strong>Given:<\/strong> P = 15 kW, V = 400 V, cos \u03c6 = 0.85, \u03b7 = 0.91, DOL k = 7<\/p>\n                <p>I<sub>rated<\/sub> = 15000 \/ (\u221a3 \u00d7 400 \u00d7 0.85 \u00d7 0.91) = <strong>28.0 A<\/strong><\/p>\n                <p>I<sub>start<\/sub> = 7 \u00d7 28.0 = <strong>196.0 A<\/strong><\/p>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<div class=\"vc-section\" id=\"vc-sec-related\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\">\n        <span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\ud83d\udd17<\/span><span class=\"vc-section-title\">Related Calculators<\/span><\/span>\n        <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>\n    <\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner\">\n            <div class=\"vc-related\">\n                <a class=\"vc-related-link\" href=\"\/calculators\/three-phase-motor-power\/\">Three-Phase Motor Power<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/vfd-selection-calculator\/\">VFD Selection<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/circuit-breaker-selection\/\">Circuit Breaker Selection<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/motor-nameplate-current\/\">Motor Nameplate Current<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/voltage-drop-calculator\/\">Voltage Drop<\/a>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<div class=\"vc-section\" id=\"vc-sec-faq\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\">\n        <span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\u2753<\/span><span class=\"vc-section-title\">Frequently Asked Questions<\/span><\/span>\n        <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>\n    <\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner\"><div class=\"vc-faq-list\" id=\"vc-faq-list\"><\/div><\/div>\n    <\/div>\n<\/div>\n\n<div class=\"vc-promo\">\n    <div class=\"vc-promo-text\"><strong>Vibromera \u2014 Portable Balancing &amp; Vibration Analysis<\/strong><br>Professional field balancing instruments and software. Used in 50+ countries.<\/div>\n    <a class=\"vc-promo-link\" href=\"https:\/\/vibromera.eu\/\" target=\"_blank\" rel=\"noopener\">Learn More<\/a>\n<\/div>\n<footer class=\"vc-footer\">\n    <p>\u00a9 2024\u20132025 <a href=\"https:\/\/vibromera.eu\/\">Vibromera<\/a> \u2014 Engineering Calculators<\/p>\n    <p style=\"font-size:12px;margin-top:4px;\">Last updated: June 2025<\/p>\n    <div class=\"vc-footer-links\"><a href=\"\/calculators\/engineering-calculators\/\">All Calculators<\/a><a href=\"https:\/\/vibromera.eu\/contacts\/\">Contact<\/a><\/div>\n<\/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='motor-starting-current';\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 methodDefaults={dol:7,stardelta:2.5,softstarter:3,vfd:1.2};\n    var methodNames={dol:'DOL (Direct On Line)',stardelta:'Star-Delta (Y-\u0394)',softstarter:'Soft Starter',vfd:'VFD \/ Inverter'};\n\n    $('vc-method').addEventListener('change',function(){\n        $('vc-kmult').value=methodDefaults[this.value];\n        calculate();\n    });\n\n    function calculate(){\n        var P=parseFloat($('vc-power').value);\n        var V=parseFloat($('vc-voltage').value);\n        var pf=parseFloat($('vc-pf').value);\n        var eff=parseFloat($('vc-eff').value);\n        var k=parseFloat($('vc-kmult').value);\n        var method=$('vc-method').value;\n        if(!P||!V||!pf||!eff||!k||P<=0||V<=0){$('vc-results').classList.remove('vc-visible');return}\n        var Irated=(P*1000)\/(Math.sqrt(3)*V*pf*eff);\n        var Istart=k*Irated;\n        var Sstart=Math.sqrt(3)*V*Istart\/1000;\n        $('vc-r-istart').innerHTML=fmt(Istart,1)+' <span class=\"vc-rcard-unit\">A<\/span>';\n        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e.preventDefault();$('vc-power').value=this.getAttribute('data-p');$('vc-voltage').value=this.getAttribute('data-v');$('vc-pf').value=this.getAttribute('data-pf');$('vc-eff').value=this.getAttribute('data-eff');$('vc-method').value=this.getAttribute('data-m');$('vc-kmult').value=this.getAttribute('data-k');calculate();\n    })});\n\n    $('vc-form').addEventListener('input',calculate);\n    $('vc-form').addEventListener('change',calculate);\n\n    $('vc-copy-btn').addEventListener('click',function(){\n        var text='Motor Starting Current\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\nStarting Current: '+$('vc-r-istart').textContent+'\\nRated Current: '+$('vc-r-irated').textContent+'\\nMultiplier: '+$('vc-r-kmult').textContent+'\\nStarting kVA: '+$('vc-r-sstart').textContent+'\\nMethod: '+$('vc-r-method').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:'What is motor starting current?',a:'<p>Motor starting current (inrush current) is the initial surge of current when a motor is first energized. For DOL starting, it is typically 6\u20138 times the rated full-load current.<\/p>'},\n        {q:'Why is starting current so high?',a:'<p>At standstill, the rotor has no back-EMF, so winding impedance is very low, resulting in high current. As the motor accelerates, back-EMF builds and current drops to the normal running value.<\/p>'},\n        {q:'What is the difference between DOL and star-delta starting?',a:'<p>DOL applies full voltage immediately (6\u20138\u00d7 current). Star-delta starts in star connection (reduced voltage per winding), reducing starting current to ~2\u20133\u00d7 rated, then switches to delta for normal running.<\/p>'},\n        {q:'How does a VFD reduce starting current?',a:'<p>A VFD controls both voltage and frequency, ramping them gradually. This allows starting with only 1\u20131.5\u00d7 rated current while providing adequate torque.<\/p>'},\n        {q:'What is the NEMA code letter for locked rotor current?',a:'<p>NEMA code letters (A\u2013V) indicate locked rotor kVA\/HP. For example, code F = 5.0\u20135.6 kVA\/HP. I<sub>start<\/sub> = (kVA\/HP \u00d7 HP \u00d7 1000) \/ (\u221a3 \u00d7 V).<\/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(entry){var key='vc_history_'+SLUG;var arr=[];try{arr=JSON.parse(localStorage.getItem(key))||[]}catch(e){}entry._ts=new Date().toISOString();arr.unshift(entry);if(arr.length>10)arr=arr.slice(0,10);try{localStorage.setItem(key,JSON.stringify(arr))}catch(e){}}\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{\n        katex.render('I_{rated} = \\\\frac{P}{\\\\sqrt{3} \\\\times V \\\\times \\\\cos\\\\varphi \\\\times \\\\eta} \\\\quad [\\\\text{A}]',$('vc-katex-1'),{displayMode:true,throwOnError:false});\n        katex.render('I_{start} = k_{start} \\\\times I_{rated} \\\\quad [\\\\text{A}]',$('vc-katex-2'),{displayMode:true,throwOnError:false});\n    }catch(e){}}\n\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 \u09ae\u09cb\u099f\u09b0 \u09b8\u09cd\u099f\u09be\u09b0\u09cd\u099f\u09bf\u0982 \u0995\u09be\u09b0\u09c7\u09a8\u09cd\u099f \u0995\u09cd\u09af\u09be\u09b2\u0995\u09c1\u09b2\u09c7\u099f\u09b0\u0964 DOL, \u09b8\u09cd\u099f\u09be\u09b0-\u09a1\u09c7\u09b2\u09cd\u099f\u09be, \u09a8\u09b0\u09ae \u09b8\u09cd\u099f\u09be\u09b0\u09cd\u099f\u09be\u09b0 \u098f\u09ac\u0982 VFD \u09aa\u09a6\u09cd\u09a7\u09a4\u09bf\u09b0 \u099c\u09a8\u09cd\u09af \u0987\u09a8\u09b0\u09be\u09b6 \u0995\u09be\u09b0\u09c7\u09a8\u09cd\u099f \u0997\u09a3\u09a8\u09be \u0995\u09b0\u09c1\u09a8\u0964 I_start = k_start \u00d7 I_rated\u0964<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100162","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100162","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":2,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100162\/revisions"}],"predecessor-version":[{"id":100937,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100162\/revisions\/100937"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/media?parent=100162"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/categories?post=100162"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/tags?post=100162"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}