{"id":100268,"date":"2026-02-15T20:06:58","date_gmt":"2026-02-15T20:06:58","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100268"},"modified":"2026-02-15T20:06:58","modified_gmt":"2026-02-15T20:06:58","slug":"trial-weight-calculator","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/bn\/calculators\/trial-weight-calculator\/","title":{"rendered":"\u09b0\u09cb\u099f\u09b0 \u09ad\u09be\u09b0\u09b8\u09be\u09ae\u09cd\u09af\u09c7\u09b0 \u099c\u09a8\u09cd\u09af \u099f\u09cd\u09b0\u09be\u09af\u09bc\u09be\u09b2 \u0993\u099c\u09a8 \u0995\u09cd\u09af\u09be\u09b2\u0995\u09c1\u09b2\u09c7\u099f\u09b0"},"content":{"rendered":"\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Trial Weight Calculator for Rotor Balancing\",\"alternateName\":[\"Trial Mass Calculator\",\"Balancing Trial Weight Calculator\"],\"description\":\"Calculate the recommended trial weight mass for single-plane rotor balancing. Based on ISO 21940 permissible unbalance, rotor mass, speed, and correction radius.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/trial-weight-calculator\/\",\"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\":\"2025-02-14\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true,\"featureList\":[\"Trial weight range calculation\",\"Balance grades G0.4 to G4000\",\"Metric and Imperial units\",\"Auto-calculation on input change\",\"URL parameter sharing\",\"Calculation history\"],\"keywords\":\"trial weight, rotor balancing, ISO 21940, correction radius, permissible unbalance\"}\n<\/script>\n\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[\n{\"@type\":\"Question\",\"name\":\"What is a trial weight in rotor balancing?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"A trial weight (also called a test weight or calibration weight) is a known mass temporarily attached to a rotor at a known radius during single-plane balancing. By measuring the vibration change caused by the trial weight, the balancing instrument calculates the correct permanent correction mass and angle. The trial weight is removed after the measurement run.\"}},\n{\"@type\":\"Question\",\"name\":\"How do I choose the right trial weight size?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The ideal trial weight should produce a measurable vibration change without overloading the rotor or bearings. A common engineering guideline is to use 5% to 10% of the permissible residual unbalance (per ISO 21940) divided by the correction radius. Too small a trial weight may not produce a reliable reading; too large may cause excessive vibration or safety hazards.\"}},\n{\"@type\":\"Question\",\"name\":\"What happens if the trial weight is too heavy?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"An excessively heavy trial weight can cause dangerously high vibration during the trial run, potentially damaging bearings, seals, or the rotor itself. It may also exceed the linear range of the vibration sensors, leading to inaccurate balancing results. Always start with the calculated minimum (5% of U_per \/ r) and increase only if the vibration change is insufficient.\"}},\n{\"@type\":\"Question\",\"name\":\"Where should I place the trial weight on the rotor?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Place the trial weight at the correction plane \u2014 the axial location where permanent balance weights will be added. For the radial position, attach it at the maximum available radius to minimize the required mass. Common attachment methods include bolting to existing holes, using magnetic weights, or taping weights to the rotor surface. Ensure the trial weight is securely attached and cannot detach during rotation.\"}},\n{\"@type\":\"Question\",\"name\":\"Why use 5\u201310% of permissible unbalance for the trial weight?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"The 5\u201310% range is a practical engineering guideline that balances two requirements: the trial weight must be heavy enough to produce a clearly measurable vibration change (signal-to-noise ratio), but light enough to avoid excessive vibration. Using permissible unbalance as the reference ensures the trial weight is scaled appropriately for the rotor's mass, speed, and balance grade.\"}}\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\":\"Trial Weight Calculator\",\"item\":\"https:\/\/vibromera.eu\/calculators\/trial-weight-calculator\/\"}\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 href=\"https:\/\/fonts.googleapis.com\/css2?family=DM+Sans:ital,opsz,wght@0,9..40,300;0,9..40,400;0,9..40,500;0,9..40,600;0,9..40,700;1,9..40,400&#038;family=JetBrains+Mono:wght@400;500;600&#038;family=Fraunces:opsz,wght@9..144,700;9..144,800&#038;display=swap\" rel=\"stylesheet\">\n\n<link rel=\"stylesheet\" href=\"https:\/\/cdn.jsdelivr.net\/npm\/katex@0.16.11\/dist\/katex.min.css\">\n\n<style>\n:root {\n    --vc-bg: #f4f1ec;\n    --vc-surface: #ffffff;\n    --vc-surface-alt: #f8f6f2;\n    --vc-ink: #1a1a1a;\n    --vc-ink-secondary: #5a5650;\n    --vc-ink-muted: #8a857e;\n    --vc-accent: #c85a2a;\n    --vc-accent-hover: #b04d22;\n    --vc-accent-light: #fdf0ea;\n    --vc-blue: #2a5c8c;\n    --vc-blue-light: #eaf1f8;\n    --vc-green: #2a7a4b;\n    --vc-green-light: #eaf8ef;\n    --vc-yellow: #a67c00;\n    --vc-yellow-light: #fef9e8;\n    --vc-red: #b91c1c;\n    --vc-red-light: #fef2f2;\n    --vc-border: #d9d4cc;\n    --vc-border-light: #e8e4dd;\n    --vc-shadow: 0 1px 3px rgba(26,26,26,0.06), 0 4px 12px rgba(26,26,26,0.04);\n    --vc-shadow-lg: 0 4px 12px rgba(26,26,26,0.08), 0 16px 40px rgba(26,26,26,0.06);\n    --vc-radius: 8px;\n    --vc-radius-lg: 12px;\n    --vc-font: 'DM Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;\n    --vc-mono: 'JetBrains Mono', 'Consolas', 'Monaco', monospace;\n    --vc-display: 'Fraunces', Georgia, serif;\n}\n\n.vc-calculator {\n    font-family: var(--vc-font);\n    font-size: 15px;\n    line-height: 1.65;\n    color: var(--vc-ink);\n    max-width: 960px;\n    margin: 0 auto;\n    padding: 20px 16px 40px;\n    -webkit-font-smoothing: antialiased;\n}\n.vc-calculator *, .vc-calculator *::before, .vc-calculator *::after { box-sizing: border-box; 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}\n    .vc-copy-btn, .vc-section-chevron, .vc-faq-chevron, .vc-presets, .vc-promo { display:none!important; }\n}\n<\/style>\n\n<div class=\"vc-calculator\" id=\"vc-trial-weight\">\n\n<!-- Header -->\n<header class=\"vc-header\">\n    <p class=\"vc-header-eyebrow\">Free Engineering Tool<\/p>\n    <h1 class=\"vc-header-title\">Trial Weight Calculator for Rotor Balancing<\/h1>\n    <p class=\"vc-header-subtitle\">Calculate the recommended trial weight mass for single-plane rotor balancing. Accounts for rotor mass, speed, correction radius, support stiffness, and vibration severity.<\/p>\n    <div class=\"vc-badges\">\n        <span class=\"vc-badge\">Vibromera Method<\/span>\n        <span class=\"vc-badge\">Support Stiffness<\/span>\n        <span class=\"vc-badge\">Vibration Level<\/span>\n    <\/div>\n<\/header>\n\n<!-- Calculator Card -->\n<div class=\"vc-card\">\n    <div class=\"vc-unit-bar\">\n        <button type=\"button\" class=\"vc-unit-btn vc-active\" data-system=\"metric\">Metric (kg, mm, g)<\/button>\n        <button type=\"button\" class=\"vc-unit-btn\" data-system=\"imperial\">Imperial (lb, in, oz)<\/button>\n    <\/div>\n\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-mass\">Rotor Mass (Mr) <span class=\"vc-label-hint\" id=\"vc-mass-unit-hint\">(kg)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-mass\" inputmode=\"decimal\" step=\"any\" min=\"0.001\" placeholder=\"e.g. 111\" value=\"111\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-speed\">Rotor Speed (N) <span class=\"vc-label-hint\">(RPM)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-speed\" inputmode=\"decimal\" step=\"any\" min=\"1\" placeholder=\"e.g. 1500\" value=\"1500\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-radius\">Installation Radius (Rt) <span class=\"vc-label-hint\" id=\"vc-radius-unit-hint\">(mm)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-radius\" inputmode=\"decimal\" step=\"any\" min=\"0.1\" placeholder=\"e.g. 150\" value=\"150\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-ksupp\">Support Stiffness (Ksupp) <span class=\"vc-label-hint\">(0.5\u20135.0)<\/span><\/label>\n                <select class=\"vc-select\" id=\"vc-ksupp\">\n                    <option value=\"5.0\">5.0 \u2014 Very rigid (massive concrete block)<\/option>\n                    <option value=\"4.0\">4.0 \u2014 Rigid (concrete foundation, stiff pedestal)<\/option>\n                    <option value=\"3.0\">3.0 \u2014 Semi-rigid (heavy steel frame, bolted base)<\/option>\n                    <option value=\"2.0\" selected>2.0 \u2014 Medium (standard industrial mount)<\/option>\n                    <option value=\"1.5\">1.5 \u2014 Medium-flexible (light frame)<\/option>\n                    <option value=\"1.0\">1.0 \u2014 Flexible (spring mounts, rubber isolators)<\/option>\n                    <option value=\"0.5\">0.5 \u2014 Very flexible (suspended, balancing jig)<\/option>\n                <\/select>\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-vib\">Vibration Level <span class=\"vc-label-hint\">(mm\/s RMS)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-vib\" inputmode=\"decimal\" step=\"any\" min=\"0.1\" placeholder=\"e.g. 5.0\" value=\"5.0\">\n            <\/div>\n        <\/div>\n\n        <!-- Presets -->\n        <div class=\"vc-presets\">\n            <div class=\"vc-presets-label\">Quick presets<\/div>\n            <button type=\"button\" class=\"vc-preset-btn\" data-m=\"45\" data-s=\"2950\" data-r=\"180\" data-ks=\"2.0\" data-v=\"6\">Fan 45 kg \/ 2950 RPM<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-m=\"120\" data-s=\"1475\" data-r=\"150\" data-ks=\"3.0\" data-v=\"8\">Pump 120 kg \/ 1475 RPM<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-m=\"350\" data-s=\"985\" data-r=\"250\" data-ks=\"4.0\" data-v=\"5\">Motor 350 kg \/ 985 RPM<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-m=\"15\" data-s=\"12000\" data-r=\"60\" data-ks=\"1.0\" data-v=\"3\">Turbocharger 15 kg \/ 12000 RPM<\/button>\n        <\/div>\n    <\/form>\n\n    <!-- Results -->\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\">Recommended Trial Weight (Mt)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-trial\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Rotor Mass (Mr)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-mass\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Trial Radius (Rt)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-radius\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Support Stiffness (Ksupp)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-ksupp\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Vibration Coefficient (Kvib)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-kvib\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Radius in cm (Rt)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-rtcm\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Speed Factor (N\/100)\u00b2<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-speedfactor\">\u2014<\/div>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- Theory & Formulas -->\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\">\n            <span class=\"vc-section-icon\">\ud83d\udcd8<\/span>\n            <span class=\"vc-section-title\">Theory &amp; Formulas<\/span>\n        <\/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>Trial Weight Formula<\/h3>\n            <p>The trial weight mass is calculated using a practical engineering formula that accounts for support conditions and vibration severity:<\/p>\n            <div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\n            <ul>\n                <li><strong>Mt<\/strong> \u2014 trial weight mass (g)<\/li>\n                <li><strong>Mr<\/strong> \u2014 rotor mass (g) \u2014 enter in kg, converted to grams internally<\/li>\n                <li><strong>Ksupp<\/strong> \u2014 support stiffness coefficient (0.5\u20135.0)<\/li>\n                <li><strong>Kvib<\/strong> \u2014 vibration level coefficient (0.5\u20133.0) \u2014 derived from measured vibration in mm\/s<\/li>\n                <li><strong>Rt<\/strong> \u2014 trial weight installation radius (cm) \u2014 enter in mm, converted to cm internally<\/li>\n                <li><strong>N<\/strong> \u2014 rotor speed (RPM)<\/li>\n            <\/ul>\n\n            <h3>Support Stiffness Coefficient (Ksupp)<\/h3>\n            <p>This coefficient accounts for how the machine support structure affects the vibration response to unbalance:<\/p>\n            <table class=\"vc-table\">\n                <thead><tr><th>Ksupp<\/th><th>Support Type<\/th><th>Description<\/th><\/tr><\/thead>\n                <tbody>\n                    <tr><td><strong>5.0<\/strong><\/td><td>Very rigid<\/td><td>Massive concrete block, stiff steel structure. Vibration barely changes with unbalance \u2014 need <strong>heavier<\/strong> trial weight (high Ksupp).<\/td><\/tr>\n                    <tr><td><strong>4.0<\/strong><\/td><td>Rigid<\/td><td>Concrete foundation, stiff pedestal. Typical for large pumps and compressors.<\/td><\/tr>\n                    <tr><td><strong>2.0\u20133.0<\/strong><\/td><td>Medium<\/td><td>Standard industrial mount, baseplate on concrete. Most common situation for fans, motors, and general machinery.<\/td><\/tr>\n                    <tr><td><strong>1.0<\/strong><\/td><td>Flexible<\/td><td>Spring mounts, rubber isolators. Machine vibrates freely \u2014 <strong>lighter<\/strong> trial weight sufficient (low Ksupp).<\/td><\/tr>\n                    <tr><td><strong>0.5<\/strong><\/td><td>Very flexible<\/td><td>Suspended mount, soft isolators, balancing jig\/cradle. Maximum vibration response \u2014 lightest trial weight.<\/td><\/tr>\n                <\/tbody>\n            <\/table>\n            <div class=\"vc-info-box\">\n                <p><strong>Rule of thumb:<\/strong> Rigid supports (Ksupp = 4\u20135) &#8220;absorb&#8221; vibration, so you need a heavier trial weight to produce a measurable change. Flexible supports (Ksupp = 0.5\u20131) amplify the response, so a lighter trial weight works.<\/p>\n            <\/div>\n\n            <h3>Vibration Level Coefficient (Kvib)<\/h3>\n            <p>This coefficient reflects the current vibration severity of the machine before balancing:<\/p>\n            <table class=\"vc-table\">\n                <thead><tr><th>Kvib<\/th><th>Vibration Level<\/th><th>Condition<\/th><\/tr><\/thead>\n                <tbody>\n                    <tr><td><strong>0.5<\/strong><\/td><td>Good (\u2264 1 mm\/s)<\/td><td>Very smooth running. Use a light trial weight so the already-low vibration signal is not overpowered.<\/td><\/tr><tr><td><strong>0.8<\/strong><\/td><td>Good (1\u20132 mm\/s)<\/td><td>Smooth running. Fine-tuning only. Light trial weight.<\/td><\/tr>\n                    <tr><td><strong>1.0<\/strong><\/td><td>Acceptable (2\u20133 mm\/s)<\/td><td>Noticeable but acceptable vibration. Standard balancing job.<\/td><\/tr>\n                    <tr><td><strong>1.2<\/strong><\/td><td>Acceptable (3\u20134.5 mm\/s)<\/td><td>Moderate unbalance. Typical field scenario.<\/td><\/tr>\n                    <tr><td><strong>1.5<\/strong><\/td><td>Elevated \/ High (4.5\u201311 mm\/s)<\/td><td>Clear, significant unbalance. The most common field-balancing case \u2014 the default range.<\/td><\/tr>\n                    <tr><td><strong>2.0<\/strong><\/td><td>Dangerous (11\u201318 mm\/s)<\/td><td>Large unbalance, urgent balancing. Heavier trial weight OK \u2014 vibration is already high.<\/td><\/tr><tr><td><strong>2.5<\/strong><\/td><td>Dangerous (18\u201328 mm\/s)<\/td><td>Severe unbalance. Heavier trial weight acceptable to ensure a measurable vector change.<\/td><\/tr><tr><td><strong>3.0<\/strong><\/td><td>Extreme (> 28 mm\/s)<\/td><td>Extreme vibration. Inspect the machine before balancing; heaviest trial-weight band.<\/td><\/tr>\n                <\/tbody>\n            <\/table>\n\n            <h3>Why This Formula Works<\/h3>\n            <p>The formula Mt = Mr \u00d7 Ksupp \u00d7 Kvib \/ (Rt \u00d7 (N\/100)\u00b2) captures the key physics:<\/p>\n            <ul>\n                <li><strong>Heavier rotors<\/strong> need heavier trial weights (linear with Mr)<\/li>\n                <li><strong>Higher speeds<\/strong> generate more centrifugal force per gram, so less trial weight is needed (inverse square of N)<\/li>\n                <li><strong>Larger radius<\/strong> means more moment per gram, so less weight needed (inverse of Rt)<\/li>\n                <li><strong>Stiffer supports<\/strong> need more weight to produce detectable vibration change (higher Ksupp = 4\u20135)<\/li>\n                <li><strong>Flexible supports<\/strong> amplify the response, so less weight is needed (lower Ksupp = 0.5\u20131)<\/li>\n                <li><strong>Higher existing vibration<\/strong> means larger existing unbalance \u2014 proportionally larger trial weight (higher Kvib)<\/li>\n            <\/ul>\n\n            <h3>Practical Example<\/h3>\n            <div class=\"vc-example-box\">\n                <div class=\"vc-example-title\">Example \u2014 Centrifugal Fan<\/div>\n                <p><strong>Given:<\/strong> Mr = 111 kg = 111,000 g, N = 1111 RPM, Rt = 111 mm = 11.1 cm, Ksupp = 1.0, Vibration = 11 mm\/s \u2192 Kvib = 1.5<\/p>\n                <p><strong>Step 1:<\/strong> Speed factor: (N\/100)\u00b2 = (1111\/100)\u00b2 = 11.11\u00b2 = 123.43<\/p>\n                <p><strong>Step 2:<\/strong> Denominator: Rt(cm) \u00d7 (N\/100)\u00b2 = 11.1 \u00d7 123.43 = 1,370.1<\/p>\n                <p><strong>Step 3:<\/strong> Numerator: Mr(g) \u00d7 Ksupp \u00d7 Kvib = 111,000 \u00d7 1.0 \u00d7 1.5 = 166,500<\/p>\n                <p><strong>Step 4:<\/strong> Mt = 166,500 \/ 1,370.1 = <strong>121.5 g<\/strong><\/p>\n                <p><strong>Result:<\/strong> Use approximately <strong>122 g<\/strong> trial weight at 111 mm radius.<\/p>\n            <\/div>\n\n            <div class=\"vc-warning-box\">\n                <p style=\"margin:0;font-size:14px;color:var(--vc-ink-secondary);\"><strong>\u26a0\ufe0f Safety Note:<\/strong> An excessively heavy trial weight can cause dangerously high vibration. If the calculated weight seems too large, start with half and increase gradually. Always ensure the trial weight is securely attached and cannot detach during rotation.<\/p>\n            <\/div>\n\n            <h3>Comparison with ISO 21940 Method<\/h3>\n            <p>The classic ISO approach uses balance grade G to calculate permissible unbalance, then takes 5\u201310% as trial weight. This Vibromera formula is a practical field shortcut that gives similar results while directly accounting for real-world conditions (support stiffness and current vibration level) that the ISO method assumes are ideal.<\/p>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- Related Calculators -->\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\">\n            <span class=\"vc-section-icon\">\ud83d\udd17<\/span>\n            <span class=\"vc-section-title\">Related Calculators<\/span>\n        <\/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\/residual-unbalance-iso1940\/\">Residual Unbalance (ISO 21940)<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/vibration-velocity\/\">Vibration Velocity (ISO 10816)<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/vibration-displacement\/\">Vibration Displacement<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/vibration-acceleration\/\">Vibration Acceleration<\/a>\n            <\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- FAQ -->\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\">\n            <span class=\"vc-section-icon\">\u2753<\/span>\n            <span class=\"vc-section-title\">Frequently Asked Questions<\/span>\n        <\/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-faq-list\" id=\"vc-faq-list\"><\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- Promo -->\n<div class=\"vc-promo\">\n    <div class=\"vc-promo-text\">\n        <strong>Vibromera \u2014 Portable Balancing &amp; Vibration Analysis<\/strong><br>\n        Professional field balancing instruments and software. Achieve ISO 21940-11 compliance on-site with Balanset series devices. Used in 50+ countries.\n    <\/div>\n    <a class=\"vc-promo-link\" href=\"https:\/\/vibromera.eu\/\" target=\"_blank\" rel=\"noopener\">Learn More<\/a>\n<\/div>\n\n<!-- Footer -->\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;\">Based on ISO 21940-11 (ISO 1940-1). Last updated: February 2025<\/p>\n    <div class=\"vc-footer-links\">\n        <a href=\"\/calculators\/engineering-calculators\/\">All Calculators<\/a>\n        <a href=\"https:\/\/vibromera.eu\/contacts\/\">Contact<\/a>\n    <\/div>\n<\/footer>\n\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\n    var SLUG = 'trial-weight-calculator';\n    var unitSystem = 'metric';\n    var KG2LB = 2.20462;\n    var MM2IN = 0.03937;\n\n    function $(id) { return document.getElementById(id); }\n    function fmt(n, d) { if(isNaN(n)) return '\u2014'; var f=n.toFixed(d===undefined?2:d); return f.replace(\/(\\.\\d*?)0+$\/,'$1').replace(\/\\.$\/,''); }\n    function fmtWeight(v) {\n        if(isNaN(v)) return '\u2014';\n        if(v >= 1000) return fmt(v\/1000, 2) + ' kg';\n        if(v >= 100) return fmt(v, 0) + ' g';\n        if(v >= 10) return fmt(v, 1) + ' g';\n        if(v >= 1) return fmt(v, 2) + ' g';\n        if(v >= 0.01) return fmt(v, 3) + ' g';\n        return v.toExponential(2) + ' g';\n    }\n\n    \/* \u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\n       CORE FORMULA:\n       Mt = Mr \u00d7 Ksupp \u00d7 Kvib \/ (Rt \u00d7 (N\/100)\u00b2)\n\n       Mt  \u2014 trial weight mass [g]\n       Mr  \u2014 rotor mass [kg]\n       Ksupp \u2014 support stiffness coefficient (1\u20135)\n       Kvib  \u2014 vibration level coefficient (0.5\u20133.0)\n       Rt  \u2014 trial weight radius [mm]\n       N   \u2014 rotor speed [RPM]\n       \u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550\u2550 *\/\n    \/* Kvib lookup: vibration mm\/s \u2192 coefficient\n       Based on Vibromera field experience *\/\n    function getKvib(vib) {\n        if (vib <= 1)   return 0.5;\n        if (vib <= 2)   return 0.8;\n        if (vib <= 3)   return 1.0;\n        if (vib <= 4.5) return 1.2;\n        if (vib <= 7.1) return 1.5;\n        if (vib <= 11)  return 1.5;\n        if (vib <= 18)  return 2.0;\n        if (vib <= 28)  return 2.5;\n        return 3.0;\n    }\n\n    function getVibLabel(vib) {\n        if (vib <= 1.8) return 'Good';\n        if (vib <= 4.5) return 'Acceptable';\n        if (vib <= 7.1) return 'Elevated';\n        if (vib <= 11)  return 'High';\n        if (vib <= 18)  return 'Dangerous';\n        return 'Extreme';\n    }\n\n    function calculate() {\n        var massVal = parseFloat($('vc-mass').value);\n        var speed = parseFloat($('vc-speed').value);\n        var radiusVal = parseFloat($('vc-radius').value);\n        var ksupp = parseFloat($('vc-ksupp').value);\n        var vib = parseFloat($('vc-vib').value);\n\n        if (!massVal || massVal <= 0 || !speed || speed <= 0 || !radiusVal || radiusVal <= 0 || !vib || vib <= 0) {\n            $('vc-results').classList.remove('vc-visible');\n            return;\n        }\n\n        \/* Convert to metric for calculation *\/\n        var massKg = unitSystem === 'imperial' ? massVal \/ KG2LB : massVal;\n        var radiusMm = unitSystem === 'imperial' ? radiusVal \/ MM2IN : radiusVal;\n\n        \/* Kvib from vibration level *\/\n        var kvib = getKvib(vib);\n\n        \/* Core formula: Mt = Mr(g) \u00d7 Ksupp \u00d7 Kvib \/ (Rt(cm) \u00d7 (N\/100)\u00b2)\n           Mr in grams (massKg \u00d7 1000)\n           Rt in centimeters (radiusMm \/ 10)\n           N in RPM *\/\n        var massG = massKg * 1000;\n        var radiusCm = radiusMm \/ 10;\n        var speedFactor = Math.pow(speed \/ 100, 2);\n        var mt = (massG * ksupp * kvib) \/ (radiusCm * speedFactor); \/* grams *\/\n\n        \/* Display results *\/\n        if (unitSystem === 'imperial') {\n            var mtOz = mt \/ 28.3495;\n            $('vc-r-trial').innerHTML = (mtOz >= 1 ? fmt(mtOz, 1) : fmt(mtOz, 3)) + ' <span class=\"vc-rcard-unit\">oz<\/span> <span style=\"font-size:14px;color:var(--vc-ink-secondary)\">(' + fmtWeight(mt) + ')<\/span>';\n            $('vc-r-mass').innerHTML = fmt(massVal, 1) + ' <span class=\"vc-rcard-unit\">lb<\/span>';\n            $('vc-r-radius').innerHTML = fmt(radiusVal, 2) + ' <span class=\"vc-rcard-unit\">in<\/span>';\n        } else {\n            $('vc-r-trial').innerHTML = fmtWeight(mt);\n            $('vc-r-mass').innerHTML = fmt(massKg, massKg >= 100 ? 0 : 1) + ' <span class=\"vc-rcard-unit\">kg<\/span>';\n            $('vc-r-radius').innerHTML = fmt(radiusMm, 0) + ' <span class=\"vc-rcard-unit\">mm<\/span>';\n        }\n\n        $('vc-r-ksupp').innerHTML = fmt(ksupp, 1);\n        $('vc-r-kvib').innerHTML = fmt(kvib, 1) + ' <span class=\"vc-rcard-unit\">(' + getVibLabel(vib) + ', ' + fmt(vib, 1) + ' mm\/s)<\/span>';\n        $('vc-r-rtcm').innerHTML = fmt(radiusCm, 1) + ' <span class=\"vc-rcard-unit\">cm<\/span>';\n        $('vc-r-speedfactor').innerHTML = fmt(speedFactor, 2);\n\n        $('vc-results').classList.add('vc-visible');\n\n        \/* URL params *\/\n        var u = new URL(window.location);\n        u.searchParams.set('mass', $('vc-mass').value);\n        u.searchParams.set('speed', speed);\n        u.searchParams.set('radius', $('vc-radius').value);\n        u.searchParams.set('ksupp', ksupp);\n        u.searchParams.set('vib', vib);\n        history.replaceState(null, '', u.toString());\n\n        \/* History *\/\n        saveHistory({\n            mass: $('vc-mass').value,\n            speed: speed,\n            radius: $('vc-radius').value,\n            ksupp: ksupp,\n            vib: vib,\n            _summary: 'Mr=' + $('vc-mass').value + (unitSystem==='imperial'?' lb':' kg') + ', N=' + speed + ' RPM, ' + vib + ' mm\/s \u2192 Mt=' + fmtWeight(mt)\n        });\n    }\n\n    \/* \u2500\u2500 UNIT TOGGLE \u2500\u2500 *\/\n    var unitBtns = document.querySelectorAll('.vc-unit-btn');\n    unitBtns.forEach(function(btn) {\n        btn.addEventListener('click', function() {\n            unitBtns.forEach(function(b) { b.classList.remove('vc-active'); });\n            this.classList.add('vc-active');\n            unitSystem = this.getAttribute('data-system');\n            $('vc-mass-unit-hint').textContent = unitSystem === 'imperial' ? '(lb)' : '(kg)';\n            $('vc-radius-unit-hint').textContent = unitSystem === 'imperial' ? '(in)' : '(mm)';\n            try { localStorage.setItem('vc_units', unitSystem); } catch(e) {}\n            calculate();\n        });\n    });\n\n    \/* \u2500\u2500 PRESETS \u2500\u2500 *\/\n    document.querySelectorAll('.vc-preset-btn').forEach(function(btn) {\n        btn.addEventListener('click', function(e) {\n            e.preventDefault();\n            var m = parseFloat(this.getAttribute('data-m'));\n            var r = parseFloat(this.getAttribute('data-r'));\n            $('vc-mass').value = unitSystem === 'imperial' ? fmt(m * KG2LB, 1) : m;\n            $('vc-speed').value = this.getAttribute('data-s');\n            $('vc-radius').value = unitSystem === 'imperial' ? fmt(r * MM2IN, 2) : r;\n            $('vc-ksupp').value = this.getAttribute('data-ks');\n            $('vc-vib').value = this.getAttribute('data-v');\n            calculate();\n        });\n    });\n\n    \/* \u2500\u2500 AUTO-CALCULATE \u2500\u2500 *\/\n    $('vc-form').addEventListener('input', calculate);\n    $('vc-form').addEventListener('change', calculate);\n\n    \/* \u2500\u2500 COPY \u2500\u2500 *\/\n    $('vc-copy-btn').addEventListener('click', function() {\n        var text = 'Trial Weight Calculation\\n' +\n            '\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\n' +\n            'Mass: ' + $('vc-mass').value + (unitSystem === 'imperial' ? ' lb' : ' kg') + '\\n' +\n            'Speed: ' + $('vc-speed').value + ' RPM\\n' +\n            'Radius: ' + $('vc-radius').value + (unitSystem === 'imperial' ? ' in' : ' mm') + '\\n' +\n            'Grade: G' + $('vc-grade').value + '\\n' +\n            'Trial Weight: ' + $('vc-r-trial').textContent + '\\n' +\n            'Uper: ' + $('vc-r-uper').textContent + '\\n' +\n            '\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\n' +\n            'vibromera.eu\/calculators\/trial-weight-calculator\/';\n\n        if (navigator.clipboard) {\n            navigator.clipboard.writeText(text).then(function() {\n                var btn = $('vc-copy-btn');\n                btn.classList.add('vc-copied');\n                btn.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!';\n                setTimeout(function() {\n                    btn.classList.remove('vc-copied');\n                    btn.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';\n                }, 2000);\n            });\n        }\n    });\n\n    \/* \u2500\u2500 COLLAPSIBLE SECTIONS \u2500\u2500 *\/\n    document.querySelectorAll('.vc-section-toggle').forEach(function(btn) {\n        btn.addEventListener('click', function() {\n            var section = this.closest('.vc-section');\n            var isOpen = section.classList.contains('vc-open');\n            section.classList.toggle('vc-open');\n            this.setAttribute('aria-expanded', !isOpen);\n        });\n    });\n\n    \/* \u2500\u2500 FAQ \u2500\u2500 *\/\n    var faqData = [\n        { q: 'What is a trial weight in rotor balancing?', a: '<p>A trial weight (also called a test weight or calibration weight) is a known mass temporarily attached to a rotor at a known radius during the trial run of single-plane balancing. By measuring the vibration change caused by the trial weight, the balancing instrument calculates the correct permanent correction mass and angle.<\/p><p>The trial weight is removed after the measurement run and replaced with the calculated correction weight.<\/p>' },\n        { q: 'What does the Ksupp (support stiffness) coefficient mean?', a: '<p>Ksupp accounts for how the machine support structure affects vibration sensitivity to unbalance:<\/p><ul><li><strong>Ksupp = 5 (very rigid)<\/strong> \u2014 Massive concrete foundations, heavy pedestals. These supports \"absorb\" unbalance forces, so you need a <strong>heavier<\/strong> trial weight to produce a measurable vibration change.<\/li><li><strong>Ksupp = 2\u20133 (medium)<\/strong> \u2014 Standard industrial mounts. Most common case.<\/li><li><strong>Ksupp = 0.5\u20131 (flexible)<\/strong> \u2014 Spring isolators, rubber mounts, balancing cradles. The machine vibrates freely, so even a <strong>small<\/strong> trial weight produces a clear response.<\/li><\/ul><p>Higher Ksupp \u2192 heavier trial weight. Lower Ksupp \u2192 lighter trial weight.<\/p>' },\n        { q: 'How does vibration level (Kvib) affect the trial weight?', a: '<p>Kvib reflects the current vibration severity before balancing:<\/p><ul><li><strong>Low vibration (Kvib \u2248 0.5\u20131.0)<\/strong> \u2014 Machine already runs fairly smooth. A smaller trial weight is needed because the existing signal is low \u2014 you don\\'t want the trial weight to dominate.<\/li><li><strong>High vibration (Kvib \u2248 2.0\u20133.0)<\/strong> \u2014 Large unbalance exists. A larger trial weight is acceptable because the machine is already vibrating heavily. The trial weight must produce a <em>noticeable change<\/em> relative to the existing vibration.<\/li><\/ul>' },\n        { q: 'Why does speed appear as (N\/100)\u00b2 in the formula?', a: '<p>Centrifugal force from unbalance increases with the <strong>square of speed<\/strong>: F = m\u00d7r\u00d7\u03c9\u00b2. At higher speeds, even a small mass creates a large force. Therefore, the trial weight can be proportionally smaller at high RPM.<\/p><p>The (N\/100)\u00b2 factor normalizes speed so the formula gives the result directly in grams. At 1000 RPM, (N\/100)\u00b2 = 100. At 3000 RPM, (N\/100)\u00b2 = 900 \u2014 requiring 9\u00d7 less trial weight.<\/p>' },\n        { q: 'Where should I place the trial weight?', a: '<p>Place the trial weight at the correction plane (axial location where permanent weights will go) and at the <strong>maximum available radius<\/strong> to minimize the required mass. Common attachment methods:<\/p><ul><li><strong>Bolt\/screw<\/strong> \u2014 Most reliable, use existing tapped holes if available<\/li><li><strong>Magnetic weight<\/strong> \u2014 Quick for steel rotors, limited to low speeds<\/li><li><strong>Adhesive tape<\/strong> \u2014 Temporary, for low-speed applications only<\/li><li><strong>Hose clamp + bolts<\/strong> \u2014 For shafts without holes<\/li><\/ul><p>Always verify the trial weight cannot detach at operating speed!<\/p>' }\n    ];\n\n    var faqList = $('vc-faq-list');\n    faqData.forEach(function(faq) {\n        faqList.innerHTML += '<div class=\"vc-faq-item\"><button type=\"button\" class=\"vc-faq-q\"><span>' + faq.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\">' + faq.a + '<\/div><\/div><\/div>';\n    });\n    faqList.addEventListener('click', function(e) {\n        var btn = e.target.closest('.vc-faq-q');\n        if (!btn) return;\n        btn.closest('.vc-faq-item').classList.toggle('vc-open');\n    });\n\n    \/* \u2500\u2500 HISTORY \u2500\u2500 *\/\n    function saveHistory(entry) {\n        var key = 'vc_history_' + SLUG;\n        var arr = [];\n        try { arr = JSON.parse(localStorage.getItem(key)) || []; } catch(e) {}\n        entry._ts = new Date().toISOString();\n        arr.unshift(entry);\n        if (arr.length > 10) arr = arr.slice(0, 10);\n        try { localStorage.setItem(key, JSON.stringify(arr)); } catch(e) {}\n    }\n\n    \/* \u2500\u2500 URL PARAMS \u2500\u2500 *\/\n    function loadParams() {\n        var p = new URLSearchParams(window.location.search);\n        p.forEach(function(v, k) { var el = $(k) || $('vc-' + k); if (el) el.value = v; });\n    }\n\n    \/* \u2500\u2500 KATEX \u2500\u2500 *\/\n    function renderFormulas() {\n        try {\n            katex.render('M_t = \\\\frac{M_r \\\\times K_{supp} \\\\times K_{vib}}{R_t \\\\times \\\\left(\\\\dfrac{N}{100}\\\\right)^2} \\\\quad [\\\\text{g}]', $('vc-katex-1'), { displayMode: true, throwOnError: false });\n        } catch(e) {}\n    }\n\n    \/* \u2500\u2500 INIT \u2500\u2500 *\/\n    function init() {\n        try {\n            var saved = localStorage.getItem('vc_units');\n            if (saved === 'imperial') {\n                unitSystem = 'imperial';\n                unitBtns.forEach(function(b) { b.classList.toggle('vc-active', b.getAttribute('data-system') === 'imperial'); });\n                $('vc-mass-unit-hint').textContent = '(lb)';\n                $('vc-radius-unit-hint').textContent = '(in)';\n            }\n        } catch(e) {}\n\n        loadParams();\n        renderFormulas();\n        calculate();\n    }\n\n    if (document.readyState === 'loading') {\n        document.addEventListener('DOMContentLoaded', init);\n    } else {\n        init();\n    }\n})();\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>\u09b0\u09cb\u099f\u09b0 \u09ad\u09be\u09b0\u09b8\u09be\u09ae\u09cd\u09af\u09aa\u09c2\u09b0\u09cd\u09a3\u0995\u09b0\u09a3\u09c7\u09b0 \u099c\u09a8\u09cd\u09af \u099f\u09cd\u09b0\u09be\u09af\u09bc\u09be\u09b2 \u0993\u099c\u09a8\u09c7\u09b0 \u09ad\u09b0 \u0997\u09a3\u09a8\u09be \u0995\u09b0\u09c1\u09a8\u0964 \u09b8\u09c2\u09a4\u09cd\u09b0: Mt = Mr \u00d7 Ksupp \u00d7 Kvib \/ (Rt \u00d7 (N\/100)\u00b2)\u0964 \u09b0\u09cb\u099f\u09b0 \u09ad\u09b0, \u0997\u09a4\u09bf, \u09b8\u0982\u09b6\u09cb\u09a7\u09a8 \u09ac\u09cd\u09af\u09be\u09b8\u09be\u09b0\u09cd\u09a7, \u09b8\u09ae\u09b0\u09cd\u09a5\u09a8 \u0995\u09a0\u09cb\u09b0\u09a4\u09be \u098f\u09ac\u0982 \u0995\u09ae\u09cd\u09aa\u09a8 \u09a4\u09c0\u09ac\u09cd\u09b0\u09a4\u09be \u09ac\u09bf\u09ac\u09c7\u099a\u09a8\u09be \u0995\u09b0\u09c7\u0964<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100268","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100268","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\/100268\/revisions"}],"predecessor-version":[{"id":100315,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/calculator\/100268\/revisions\/100315"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/media?parent=100268"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/categories?post=100268"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/bn\/wp-json\/wp\/v2\/tags?post=100268"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}