{"id":132,"date":"2026-08-27T19:53:24","date_gmt":"2026-08-27T19:53:24","guid":{"rendered":"https:\/\/axtron.group\/blog\/?p=132"},"modified":"2026-08-27T20:29:46","modified_gmt":"2026-08-27T20:29:46","slug":"how-to-size-a-ups-for-your-project-kva-kw-battery-runtime","status":"publish","type":"post","link":"https:\/\/axtron.group\/blog\/power-backup-systems\/how-to-size-a-ups-for-your-project-kva-kw-battery-runtime\/","title":{"rendered":"How to Size a UPS for your Project: kVA, kW &amp; Battery Runtime"},"content":{"rendered":"\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-260dca5f wp-block-columns-is-layout-flex\" style=\"margin-top:0;margin-bottom:0\">\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\">\n<h2 class=\"wp-block-heading has-text-align-left has-superbfont-large-font-size\">How to Size a UPS for your Project<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>What size UPS do I need?<\/strong> The answer depends on more than the total watts of your computers or equipment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A properly sized UPS must have enough <strong>kW and kVA capacity<\/strong> to carry the connected load while also providing the required <strong>battery backup runtime<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This applies whether you are protecting a few computers, an office, CCTV system, server room, data centre or critical commercial equipment.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\" style=\"padding-right:0;padding-bottom:0;padding-left:0\">\n<div><div class=\"wp-block-image is-style-default\">\n<figure class=\"alignleft size-full has-custom-border\"><img loading=\"lazy\" decoding=\"async\" width=\"1000\" height=\"666\" src=\"https:\/\/axtron.group\/blog\/wp-content\/uploads\/2026\/08\/serv-02-x.png\" alt=\"\" class=\"wp-image-136\" style=\"border-radius:20px\" srcset=\"https:\/\/axtron.group\/blog\/wp-content\/uploads\/2026\/08\/serv-02-x.png 1000w, https:\/\/axtron.group\/blog\/wp-content\/uploads\/2026\/08\/serv-02-x-300x200.png 300w, https:\/\/axtron.group\/blog\/wp-content\/uploads\/2026\/08\/serv-02-x-768x511.png 768w, https:\/\/axtron.group\/blog\/wp-content\/uploads\/2026\/08\/serv-02-x-850x566.png 850w\" sizes=\"auto, (max-width: 1000px) 100vw, 1000px\" \/><\/figure>\n<\/div><\/div>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignfull\" style=\"margin-top:var(--wp--preset--spacing--superbspacing-small);margin-bottom:var(--wp--preset--spacing--superbspacing-small);padding-top:var(--wp--preset--spacing--superbspacing-xxlarge);padding-right:var(--wp--preset--spacing--superbspacing-small);padding-bottom:var(--wp--preset--spacing--superbspacing-xxlarge);padding-left:var(--wp--preset--spacing--superbspacing-small)\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-container-core-group-is-layout-b15c4938 wp-block-group-is-layout-constrained\">\n<div class=\"wp-block-columns alignwide is-layout-flex wp-container-core-columns-is-layout-3b3b0ade wp-block-columns-is-layout-flex\" style=\"margin-top:0;margin-bottom:0;padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<h2 class=\"wp-block-heading has-text-align-left has-contrast-color has-text-color has-superbfont-large-font-size\">Identify the Equipment the UPS Will Protect<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Start with the critical equipment that must remain powered during an outage.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Typical UPS loads include:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Servers<\/li>\n\n\n\n<li>Computers<\/li>\n\n\n\n<li>Network switches<\/li>\n\n\n\n<li>Routers<\/li>\n\n\n\n<li>CCTV and NVR systems<\/li>\n\n\n\n<li>Access control<\/li>\n\n\n\n<li>Telecommunications equipment<\/li>\n\n\n\n<li>POS systems<\/li>\n\n\n\n<li>Industrial controls<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Whenever possible, use actual equipment wattage rather than estimates.<\/strong><\/p>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-left has-contrast-color has-text-color has-superbfont-large-font-size\">Check Both kW and kVA<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A UPS may have both a <strong>kVA rating and a kW rating.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">These are not always the same.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For example, one 10kVA UPS may support 10kW, while another older design may support only 9kW or 8kW.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Your selected UPS therefore needs to satisfy <strong>both the required kW and kVA.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For modern IT installations, this is particularly important because server and networking loads can have high power factors.<\/p>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-left has-contrast-color has-text-color has-superbfont-large-font-size\">Choose the Correct Phase Configuration<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">UPS systems commonly come as:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Single-phase in \/ Single-phase out<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Three-phase in \/ Single-phase out<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Three-phase in \/ Three-phase out<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A three-phase building does not automatically require every protected device to be three phase.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A large bank of single-phase servers, computers or network equipment can be distributed across the three output phases of a suitable three-phase UPS.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The key is good <strong>phase balancing<\/strong>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Don&#8217;t Oversize for Every Short Power Peak<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">UPS inverters generally have some short-term <strong>overload capability<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">That means a brief equipment startup peak does not always require a UPS whose continuous rating equals the peak.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For example, server power supplies may briefly demand more power during a simultaneous restart.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If that demand falls within the UPS manufacturer&#8217;s permitted overload level and duration, the UPS may carry it without requiring a larger continuous rating.<\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"wp-block-paragraph\">This can prevent unnecessary oversizing.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">However, actual UPS overload curves and bypass behaviour must always be checked before final selection.<\/p>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-left has-contrast-color has-text-color has-superbfont-large-font-size\">Battery Runtime Is a Separate Calculation<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">If you are sizing a <strong>three-phase generator<\/strong>, single-phase equipment should be distributed reasonably across: <strong>L1, L2 and L3.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">You should not multiply every single-phase load by three, and you should not automatically assume all single-phase equipment is connected to one phase.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Good phase balancing allows better use of the generator&#8217;s available capacity.<\/p>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-left has-contrast-color has-text-color has-superbfont-large-font-size\">Consider UPS and Battery-Charging Loads<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A <strong>10kVA UPS does not have a fixed backup time<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The same UPS could provide five minutes, thirty minutes or several hours depending on its battery system and actual load.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Battery sizing depends on: <strong>Load kW \u00d7 required backup time<\/strong> with additional consideration for:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>UPS efficiency<\/li>\n\n\n\n<li>Battery chemistry<\/li>\n\n\n\n<li>Usable battery capacity<\/li>\n\n\n\n<li>Battery age<\/li>\n\n\n\n<li>Temperature<\/li>\n\n\n\n<li>Discharge rate<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">This is why UPS capacity and UPS battery runtime should be calculated separately.<\/p>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-left has-contrast-color has-text-color has-superbfont-large-font-size\">Decide How Much Backup Time You Actually Need<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Ask what the battery is expected to achieve.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If a generator normally starts within a few minutes, the UPS may only need enough battery capacity to bridge the transfer period.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If there is no generator, you may require significantly more battery storage.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For offices and server rooms, choosing the right runtime can make a major difference to system cost.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Leave Sensible Room for Growth<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A UPS should not normally be selected to operate permanently at its absolute limit.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Some capacity should remain for:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Additional equipment<\/li>\n\n\n\n<li>Short load changes<\/li>\n\n\n\n<li>Future growth<\/li>\n\n\n\n<li>Operating reserve<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The answer, however, is not always to double the UPS size.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Good UPS sizing balances <strong>capacity, runtime, resilience and cost<\/strong>.<\/p>\n<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-group alignfull\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<div class=\"wp-block-group alignfull\" style=\"margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--superbspacing-medium);padding-right:var(--wp--preset--spacing--superbspacing-small);padding-bottom:var(--wp--preset--spacing--superbspacing-large);padding-left:var(--wp--preset--spacing--superbspacing-small)\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-container-core-group-is-layout-7daff50c wp-block-group-is-layout-constrained\">\n<h2 class=\"wp-block-heading has-text-align-center has-contrast-color has-text-color has-superbfont-large-font-size\">Use Our UPS Sizing Calculator<\/h2>\n\n\n\n<div class=\"wp-block-group alignwide is-vertical is-content-justification-center is-layout-flex wp-container-core-group-is-layout-6a3c724d wp-block-group-is-layout-flex\" style=\"border-radius:20px;padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-group is-content-justification-center\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-container-core-group-is-layout-f4748acb wp-block-group-is-layout-constrained\">\n<p class=\"wp-block-paragraph\">Use our free <strong>UPS Sizing Calculator for Ghana<\/strong> to estimate the UPS <strong>kVA, kW and battery capacity<\/strong> required for your equipment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Add your servers, computers, networking equipment or other critical loads, choose the desired backup runtime and receive a preliminary UPS sizing recommendation before final engineering selection.<\/p>\n<\/div><\/div>\n<\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<div class=\"wp-block-buttons is-content-justification-center is-layout-flex wp-container-core-buttons-is-layout-fe48e5de wp-block-buttons-is-layout-flex\">\n<div class=\"wp-block-button\"><a class=\"wp-block-button__link wp-element-button\" href=\"https:\/\/axtron.group\/store\/power-sizing-tools\/\" target=\"_blank\" rel=\"noopener\">Generator Sizing Calculator<\/a><\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-group\" style=\"padding-top:var(--wp--preset--spacing--superbspacing-small)\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-container-core-group-is-layout-845efc53 wp-block-group-is-layout-constrained\">\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-8f761849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column has-mono-4-background-color has-background is-layout-flow wp-block-column-is-layout-flow\" style=\"padding-top:var(--wp--preset--spacing--superbspacing-small);padding-right:var(--wp--preset--spacing--superbspacing-small);padding-bottom:var(--wp--preset--spacing--superbspacing-small);padding-left:var(--wp--preset--spacing--superbspacing-small)\"><div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" src=\"https:\/\/axtron.group\/blog\/wp-content\/uploads\/2025\/10\/img-icon-4.png\" alt=\"\" style=\"object-fit:cover;width:48px;height:48px\"\/><\/figure>\n<\/div>\n\n\n<h3 class=\"wp-block-heading has-text-align-center has-mono-1-color has-text-color has-link-color has-superbfont-medium-font-size wp-elements-1\" style=\"margin-top:0;margin-bottom:0\">Email Support<\/h3>\n\n\n\n<p class=\"has-text-align-center has-mono-2-color has-text-color has-superbfont-xsmall-font-size wp-block-paragraph\" style=\"margin-top:var(--wp--preset--spacing--superbspacing-xxsmall);margin-bottom:0\"><strong>support@axtrongroup.com<\/strong><\/p>\n<\/div>\n\n\n\n<div class=\"wp-block-column has-mono-4-background-color has-background is-layout-flow wp-block-column-is-layout-flow\" style=\"padding-top:var(--wp--preset--spacing--superbspacing-small);padding-right:var(--wp--preset--spacing--superbspacing-small);padding-bottom:var(--wp--preset--spacing--superbspacing-small);padding-left:var(--wp--preset--spacing--superbspacing-small)\"><div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img decoding=\"async\" src=\"https:\/\/axtron.group\/blog\/wp-content\/uploads\/2025\/10\/icon-mobile.png\" alt=\"\" style=\"object-fit:cover;width:48px;height:48px\"\/><\/figure>\n<\/div>\n\n\n<h3 class=\"wp-block-heading has-text-align-center has-mono-1-color has-text-color has-superbfont-medium-font-size\" style=\"margin-top:0;margin-bottom:0\">Phone Support<\/h3>\n\n\n\n<p class=\"has-text-align-center has-mono-2-color has-text-color has-superbfont-xsmall-font-size wp-block-paragraph\" style=\"margin-top:var(--wp--preset--spacing--superbspacing-xxsmall);margin-bottom:0\"><strong>+233(0)50 364 7036<\/strong><\/p>\n<\/div>\n<\/div>\n<\/div><\/div>\n<\/div><\/div>\n<\/div><\/div>\n\n\n\n<div class=\"wp-block-group alignfull\" style=\"margin-top:0;margin-bottom:0;padding-top:var(--wp--preset--spacing--superbspacing-xxlarge);padding-right:var(--wp--preset--spacing--superbspacing-medium);padding-bottom:var(--wp--preset--spacing--superbspacing-xxlarge);padding-left:var(--wp--preset--spacing--superbspacing-medium)\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-container-core-group-is-layout-7e3202bb wp-block-group-is-layout-constrained\">\n<div class=\"wp-block-group alignwide\" style=\"margin-top:0;margin-bottom:var(--wp--preset--spacing--superbspacing-large);padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\"><div class=\"wp-block-image is-style-default\">\n<figure class=\"aligncenter size-full has-custom-border\"><img loading=\"lazy\" decoding=\"async\" width=\"1000\" height=\"316\" src=\"https:\/\/axtron.group\/blog\/wp-content\/uploads\/2026\/08\/serv-03-x-edited.png\" alt=\"\" class=\"wp-image-138\" style=\"border-radius:20px\" srcset=\"https:\/\/axtron.group\/blog\/wp-content\/uploads\/2026\/08\/serv-03-x-edited.png 1000w, https:\/\/axtron.group\/blog\/wp-content\/uploads\/2026\/08\/serv-03-x-edited-300x95.png 300w, https:\/\/axtron.group\/blog\/wp-content\/uploads\/2026\/08\/serv-03-x-edited-768x243.png 768w, https:\/\/axtron.group\/blog\/wp-content\/uploads\/2026\/08\/serv-03-x-edited-850x269.png 850w\" sizes=\"auto, (max-width: 1000px) 100vw, 1000px\" \/><\/figure>\n<\/div><\/div><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-left has-contrast-color has-text-color has-superbfont-large-font-size\">Final thought \u2014 balance capacity, runtime and resilience<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"has-superbfont-small-font-size wp-block-paragraph\">A good UPS system is not simply the biggest unit your budget allows. It should comfortably carry your critical equipment, provide the backup time you actually need and leave sensible room for short-term overloads and future growth. The practical approach is to size the UPS around the real load, size the batteries around the required runtime, and then confirm that the complete system delivers the level of resilience your operation depends on.<\/p>\n<\/div><\/div>\n<\/div><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>What size UPS do I need? The answer depends on more than the total watts of your computers or equipment.<\/p>\n<p>A properly sized UPS must have enough kW and kVA capacity to carry the connected load while also providing the required battery backup runtime.<\/p>\n<p>This applies whether you are protecting a few computers, an office, CCTV system, server room, data centre or critical commercial equipment.<\/p>\n","protected":false},"author":1,"featured_media":133,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[68,67,66],"tags":[49,81,87,86,78,85,88,83,84,82,80,51],"class_list":["post-132","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-guides-resources","category-industry-technology","category-power-backup-systems","tag-backup-power","tag-battery-backup","tag-critical-power","tag-data-centre","tag-ghana","tag-server-room","tag-three-phase-ups","tag-ups-kva","tag-ups-kw","tag-ups-runtime","tag-ups-sizing","tag-ups-systems"],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/axtron.group\/blog\/wp-content\/uploads\/2026\/08\/serv-01.jpg","_links":{"self":[{"href":"https:\/\/axtron.group\/blog\/wp-json\/wp\/v2\/posts\/132","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/axtron.group\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/axtron.group\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/axtron.group\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/axtron.group\/blog\/wp-json\/wp\/v2\/comments?post=132"}],"version-history":[{"count":2,"href":"https:\/\/axtron.group\/blog\/wp-json\/wp\/v2\/posts\/132\/revisions"}],"predecessor-version":[{"id":141,"href":"https:\/\/axtron.group\/blog\/wp-json\/wp\/v2\/posts\/132\/revisions\/141"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/axtron.group\/blog\/wp-json\/wp\/v2\/media\/133"}],"wp:attachment":[{"href":"https:\/\/axtron.group\/blog\/wp-json\/wp\/v2\/media?parent=132"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/axtron.group\/blog\/wp-json\/wp\/v2\/categories?post=132"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/axtron.group\/blog\/wp-json\/wp\/v2\/tags?post=132"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}