{"id":11,"date":"2026-11-01T14:08:36","date_gmt":"2026-11-01T14:08:36","guid":{"rendered":"https:\/\/holdvolt.com\/blog\/?p=11"},"modified":"2026-11-01T14:08:36","modified_gmt":"2026-11-01T14:08:36","slug":"sample-protect-plcs-drives-robots-industrial-ups","status":"publish","type":"post","link":"https:\/\/holdvolt.com\/blog\/sample-protect-plcs-drives-robots-industrial-ups\/","title":{"rendered":"How to Protect PLCs, Drives and Robots on a Factory Line with an Industrial UPS"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">A voltage dip of a fraction of a second can stop a line for an hour. The motors ride through it. The controller does not, and the restart is what costs you: scrapped product in the machine, lost recipes, and a robot that has to be homed by hand.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Putting the whole line behind one large system is rarely the answer. Start by sorting the load.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Sort the load by what happens when it stops<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>Load group<\/th><th>Typical items<\/th><th>If power is lost<\/th><th>Usual protection<\/th><\/tr><\/thead><tbody><tr><td>Control<\/td><td>PLCs, HMIs, safety relays, sensors, I\/O<\/td><td>Line stops, state and recipes can be lost<\/td><td>Always on the online UPS<\/td><\/tr><tr><td>Data<\/td><td>SCADA, MES terminals, network switches, historians<\/td><td>Records and traceability are lost<\/td><td>Always on the online UPS<\/td><\/tr><tr><td>Motion<\/td><td>Servo drives, robot controllers<\/td><td>Uncontrolled stop, re-homing, possible collision<\/td><td>Case by case, see below<\/td><\/tr><tr><td>Process power<\/td><td>Large motors, pumps, heaters, compressors<\/td><td>Slow or safe stop in most cases<\/td><td>Usually not on the UPS<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/holdvolt.com\/blog\/wp-content\/uploads\/2026\/11\/sample-x33_60-200kva_01-screenoff.webp\" alt=\"Three-phase online UPS cabinet, front view\"\/><figcaption class=\"wp-element-caption\">A three-phase cabinet sits close to the panels it protects, which keeps the protected wiring short.<\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Control and data: the easy decision<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Control and data loads are small compared with the line and very sensitive to dips, so they should always sit behind a double-conversion unit. Several minutes of runtime is often enough to ride through a dip, save state and shut down in order.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Drives and robots: decide by the stop you want<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Motion is where the real decisions are. There are two common approaches:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n\n<li><strong>Protect the controller only.<\/strong> The robot stops when the drive power goes, but the controller stays alive, keeps its position and reports what happened. This is usually enough, and much cheaper.<\/li>\n\n\n<li><strong>Protect the drives too.<\/strong> Worth it when a process must finish its motion, for example a robot holding a part in a press or a hot process that cannot stop halfway. Size for regeneration and peak current, not average power.<\/li>\n\n<\/ul>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">Ask the machine builder which stop category the machine expects on power loss. The answer usually decides whether the drives need protection at all.<\/p>\n<\/blockquote>\n\n\n\n<h2 class=\"wp-block-heading\">Sizing notes specific to the factory floor<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n\n<li><strong>Inrush.<\/strong> Direct-on-line motors commonly draw 6 to 8 times running current at start. Keep them off the UPS, or size for them. A transformer-based unit tolerates this better; see <a href=\"\/guides\/transformer-vs-transformerless-ups\/\">transformer-based vs transformerless<\/a><\/li>\n\n\n<li><strong>Harmonics.<\/strong> Drives draw non-sinusoidal current. Check the output distortion the unit is rated for with a non-linear load.<\/li>\n\n\n<li><strong>Heat and dust.<\/strong> Check the rated ambient temperature, and whether filters are fitted and can be changed without shutting down.<\/li>\n\n\n<li><strong>Maintenance bypass.<\/strong> A line that runs around the clock needs a way to service the unit without stopping production.<\/li>\n\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">What to send when you ask for a quote<\/h2>\n\n\n\n<ol class=\"wp-block-list\">\n\n<li>A load list by group, in kW and kVA, with single-phase or three-phase marked.<\/li>\n\n\n<li>Input voltage, frequency and how unstable the grid is on site.<\/li>\n\n\n<li>The runtime you want, and what should happen when it ends.<\/li>\n\n\n<li>Ambient temperature, altitude and room size.<\/li>\n\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">More on this application: <a href=\"\/applications\/manufacturing\/\">power protection for manufacturing<\/a> and the <a href=\"\/industrial-ups\/\">industrial UPS range<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>You rarely need to back up the whole line. Split the load by what happens when it loses power, then protect each group for what it actually needs.<\/p>\n","protected":false},"author":1,"featured_media":12,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","rank_math_title":"","rank_math_description":"","rank_math_focus_keyword":"","rank_math_canonical_url":"","_elementor_edit_mode":""},"categories":[3],"tags":[],"class_list":["post-11","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-applications"],"_links":{"self":[{"href":"https:\/\/holdvolt.com\/blog\/wp-json\/wp\/v2\/posts\/11","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/holdvolt.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/holdvolt.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/holdvolt.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/holdvolt.com\/blog\/wp-json\/wp\/v2\/comments?post=11"}],"version-history":[{"count":1,"href":"https:\/\/holdvolt.com\/blog\/wp-json\/wp\/v2\/posts\/11\/revisions"}],"predecessor-version":[{"id":13,"href":"https:\/\/holdvolt.com\/blog\/wp-json\/wp\/v2\/posts\/11\/revisions\/13"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/holdvolt.com\/blog\/wp-json\/wp\/v2\/media\/12"}],"wp:attachment":[{"href":"https:\/\/holdvolt.com\/blog\/wp-json\/wp\/v2\/media?parent=11"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/holdvolt.com\/blog\/wp-json\/wp\/v2\/categories?post=11"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/holdvolt.com\/blog\/wp-json\/wp\/v2\/tags?post=11"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}