{"id":46426,"date":"2025-12-07T13:00:24","date_gmt":"2025-12-07T13:00:24","guid":{"rendered":"https:\/\/maritimehub.co.uk\/?page_id=46426"},"modified":"2026-04-27T23:29:35","modified_gmt":"2026-04-27T22:29:35","slug":"eto","status":"publish","type":"page","link":"https:\/\/maritimehub.co.uk\/eto\/","title":{"rendered":"eto"},"content":{"rendered":"\n<!-- =========================================================\nMaritimeHub \u2013 ETO & Electrical Hub (HTML drop-in)\nSame nav pattern as AIS \/ Engine \/ Bridge \/ On Deck.\n========================================================= -->\n\n<div class=\"mh-eto-mobilebar\" role=\"navigation\" aria-label=\"ETO mobile\">\n  <button class=\"mh-eto-mobilebar__toggle\" type=\"button\" id=\"mhEtoDrawerOpen\" aria-controls=\"mhEtoDrawer\" aria-expanded=\"false\">\n    <svg viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\"><rect y=\"2\" width=\"16\" height=\"2\" rx=\"1\"\/><rect y=\"7\" width=\"16\" height=\"2\" rx=\"1\"\/><rect y=\"12\" width=\"16\" height=\"2\" rx=\"1\"\/><\/svg>\n    Contents\n  <\/button>\n  <div class=\"mh-eto-mobilebar__title\">ETO &amp; Electrical<\/div>\n  <span class=\"mh-eto-mobilebar__spacer\"><\/span>\n<\/div>\n\n<div class=\"mh-eto-drawer-backdrop\" id=\"mhEtoDrawerBackdrop\" aria-hidden=\"true\"><\/div>\n<aside class=\"mh-eto-drawer\" id=\"mhEtoDrawer\" aria-hidden=\"true\" aria-label=\"ETO navigation\">\n  <div class=\"mh-eto-drawer__head\">\n    <span class=\"mh-eto-drawer__title\">ETO &amp; Electrical<\/span>\n    <button class=\"mh-eto-drawer__close\" type=\"button\" id=\"mhEtoDrawerClose\" aria-label=\"Close menu\">\u00d7<\/button>\n  <\/div>\n  <div class=\"mh-eto-drawer__body\"><\/div>\n<\/aside>\n\n<div class=\"mh-eto-shell\">\n\n  <nav class=\"mh-eto-nav\" id=\"mhEtoPrimaryNav\" aria-label=\"ETO sections\">\n    <p class=\"mh-eto-nav-title\">ETO &amp; Electrical<\/p>\n    <ul class=\"mh-eto-tree\">\n      <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path \/><\/svg>\n\n      <li class=\"mh-eto-cat\" data-open=\"true\">\n        <button class=\"mh-eto-cat-toggle\" type=\"button\">Fundamentals, Safety &amp; Distribution<span class=\"caret\">\u25be<\/span><\/button>\n        <ul>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/electrical-principles-standards\/\">Electrical Principles &amp; Standards<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/safety-loto-arc-flash-hv-work\/\">Safety: LOTO, Arc-Flash &amp; HV Work<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/hv-power-3-3-11-kv\/\">HV Power (3.3&ndash;11 kV)<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/lv-distribution\/\">LV Distribution<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/switchboards-mccs\/\">Switchboards &amp; MCCs<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/protection-coordination\/\">Protection &amp; Coordination<\/a><\/li>\n        <\/ul>\n      <\/li>\n\n      <li class=\"mh-eto-cat\" data-open=\"false\">\n        <button class=\"mh-eto-cat-toggle\" type=\"button\">Generation, Propulsion &amp; Quality<span class=\"caret\">\u25be<\/span><\/button>\n        <ul>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/generators-avr-excitation\/\">Generators, AVR &amp; Excitation<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/pms-load-sharing-shedding-blackout\/\">PMS: Load Sharing, Shedding &amp; Blackout<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/shore-power-cold-ironing-energy-management\/\">Shore Power \/ Cold Ironing<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/transformers-rectifiers-inverters\/\">Transformers, Rectifiers &amp; Inverters<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/motors-starters-vfds\/\">Motors, Starters &amp; VFDs<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/electric-propulsion-thrusters\/\">Electric Propulsion &amp; Thrusters<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/ups-batteries-ess\/\">UPS, Batteries &amp; ESS<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/power-quality-harmonics\/\">Power Quality &amp; Harmonics<\/a><\/li>\n        <\/ul>\n      <\/li>\n\n      <li class=\"mh-eto-cat\" data-open=\"false\">\n        <button class=\"mh-eto-cat-toggle\" type=\"button\">Systems, Maintenance &amp; Tools<span class=\"caret\">\u25be<\/span><\/button>\n        <ul>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/cabling-glanding-earthing-emc\/\">Cabling, Glanding, Earthing &amp; EMC<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/lighting-navigation-comms-power\/\">Lighting, Nav &amp; Comms Power<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/automation-instrumentation-control\/\">Automation, Instrumentation &amp; Control<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/fire-gas-detection-hazardous-areas\/\">Fire\/Gas Detection &amp; Hazardous Areas<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/auxiliary-systems\/\">Auxiliary Systems<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/specialized-rigs-dp-plants-megayachts\/\">Rigs, DP Plants &amp; Megayachts<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/maintenance-testing-cmms\/\">Maintenance, Testing &amp; CMMS<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/documentation-drawings-compliance\/\">Documentation, Drawings &amp; Compliance<\/a><\/li>\n          <li><a href=\"https:\/\/maritimehub.co.uk\/checklists-sops-test-records\/\">Checklists, SOPs &amp; Test Records<\/a><\/li>\n          <li><a class=\"mh-eto-link-tools\" href=\"https:\/\/maritimehub.co.uk\/calculators-data-sheets\/\">Calculators &amp; Tools<\/a><\/li>\n        <\/ul>\n      <\/li>\n\n    <\/ul>\n  <\/nav>\n\n  <main class=\"mh-eto-main\">\n\n    <section class=\"mh-eto-hero\">\n      <div class=\"mh-eto-hero-top\">\n        <div class=\"mh-eto-hero-left\">\n          <span class=\"mh-eto-eyebrow\">ETO &amp; Electrical<\/span>\n          <h1>ETO &amp; Electrical Systems Hub<\/h1>\n          <p>High-voltage, low-voltage, automation and power management in one structured space. Use the left-hand menu to move between topics without leaving the section.<\/p>\n        <\/div>\n        <div class=\"mh-eto-hero-right\">\n          <img decoding=\"async\" src=\"https:\/\/maritimehub.co.uk\/wp-content\/uploads\/2026\/04\/Picture2.jpg\" alt=\"ETO and Electrical Systems hub hero image\" loading=\"lazy\">\n        <\/div>\n      <\/div>\n\n      <div class=\"mh-eto-cta-row\">\n        <a class=\"mh-eto-cta\" href=\"https:\/\/maritimehub.co.uk\/electrical-principles-standards\/\">\n          <img decoding=\"async\" class=\"mh-eto-cta-icon\" src=\"https:\/\/maritimehub.co.uk\/wp-content\/uploads\/2026\/01\/elearning_4651496.png\" alt=\"\" width=\"34\" height=\"34\" loading=\"lazy\">\n          <div class=\"mh-eto-cta-title\">Build Foundations<\/div>\n          <div class=\"mh-eto-cta-sub\">New to shipboard power or revising for HV endorsement and orals.<\/div>\n        <\/a>\n        <a class=\"mh-eto-cta\" href=\"https:\/\/maritimehub.co.uk\/pms-load-sharing-shedding-blackout\/\">\n          <img decoding=\"async\" class=\"mh-eto-cta-icon\" src=\"https:\/\/maritimehub.co.uk\/wp-content\/uploads\/2026\/01\/10595761.png\" alt=\"\" width=\"34\" height=\"34\" loading=\"lazy\">\n          <div class=\"mh-eto-cta-title\">Solve a Fault<\/div>\n          <div class=\"mh-eto-cta-sub\">Trips, blackouts, alarms or strange readings on PMS and protection.<\/div>\n        <\/a>\n        <a class=\"mh-eto-cta\" href=\"https:\/\/maritimehub.co.uk\/calculators-data-sheets\/\">\n          <img decoding=\"async\" class=\"mh-eto-cta-icon\" src=\"https:\/\/maritimehub.co.uk\/wp-content\/uploads\/2026\/01\/tollbox_9847813.png\" alt=\"\" width=\"34\" height=\"34\" loading=\"lazy\">\n          <div class=\"mh-eto-cta-title\">Tools &amp; Test Sheets<\/div>\n          <div class=\"mh-eto-cta-sub\">Test records, protection setting sheets, cable sizing, harmonic checks.<\/div>\n        <\/a>\n      <\/div>\n    <\/section>\n\n    <section class=\"mh-eto-block\" id=\"on-watch\">\n      <div class=\"mh-eto-block-head\">\n        <h2>On Watch<\/h2>\n        <p>Fast entry points for the electrical issues that get you called to the switchboard room at 03:00.<\/p>\n      <\/div>\n      <div class=\"mh-eto-cards\">\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/generators-avr-excitation\/\">\n          <strong>Generator won&#8217;t parallel \/ unstable voltage<\/strong>\n          <span>AVR behaviour, excitation checks, synchronising &mdash; before and after paralleling.<\/span>\n        <\/a>\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/pms-load-sharing-shedding-blackout\/\">\n          <strong>Unexpected load-shedding or blackout<\/strong>\n          <span>PMS logic, priority tables, blackout recovery, non-essential trip sequence.<\/span>\n        <\/a>\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/motors-starters-vfds\/\">\n          <strong>Motor tripping on start or VFD faults<\/strong>\n          <span>Starting current, DOL vs soft-start vs VFD, common fault codes, cable faults.<\/span>\n        <\/a>\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/ups-batteries-ess\/\">\n          <strong>UPS alarms \/ degraded autonomy<\/strong>\n          <span>Battery health, bypass behaviour, autonomy testing, critical-load mapping.<\/span>\n        <\/a>\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/power-quality-harmonics\/\">\n          <strong>Nuisance trips from harmonics or THD<\/strong>\n          <span>VFD-driven harmonics, resonance, filter health, measurement discipline.<\/span>\n        <\/a>\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/safety-loto-arc-flash-hv-work\/\">\n          <strong>HV permit about to expire<\/strong>\n          <span>Safe isolation, proving dead, earthing, the specific hazards of 3.3&ndash;11 kV work.<\/span>\n        <\/a>\n      <\/div>\n    <\/section>\n\n    <section class=\"mh-eto-block\" id=\"fault-finder\">\n      <div class=\"mh-eto-block-head\">\n        <h2>Fault Finder &amp; High-Risk Work<\/h2>\n        <p>Structured fault paths and the electrical jobs that demand the most discipline.<\/p>\n      <\/div>\n      <div class=\"mh-eto-cards\">\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/protection-coordination\/\">\n          <strong>Protection &amp; Coordination<\/strong>\n          <span>Relay settings, discrimination, fault level estimates, trip test records.<\/span>\n        <\/a>\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/pms-load-sharing-shedding-blackout\/\">\n          <strong>Blackout Recovery<\/strong>\n          <span>Black-start sequence, essential restoration, DG priority, lessons from real events.<\/span>\n        <\/a>\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/safety-loto-arc-flash-hv-work\/\">\n          <strong>Arc-Flash &amp; HV Permits<\/strong>\n          <span>What a safe HV work pack looks like &mdash; PPE category, boundaries, proving dead.<\/span>\n        <\/a>\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/shore-power-cold-ironing-energy-management\/\">\n          <strong>Shore Power Integration<\/strong>\n          <span>Cold-ironing on older ships, synchronisation, earthing, interface protection.<\/span>\n        <\/a>\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/motors-starters-vfds\/\">\n          <strong>VFD Troubleshooting<\/strong>\n          <span>Common fault codes, dv\/dt issues, motor-cable length limits, bearing currents.<\/span>\n        <\/a>\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/fire-gas-detection-hazardous-areas\/\">\n          <strong>Hazardous-Area Equipment<\/strong>\n          <span>Ex ratings, certified repairs, inspection grades, what a failed certification looks like.<\/span>\n        <\/a>\n      <\/div>\n    <\/section>\n\n    <section class=\"mh-eto-block\" id=\"visuals\">\n      <div class=\"mh-eto-block-head\">\n        <h2>Core References &amp; Visuals<\/h2>\n        <p>Key electrical reference points &mdash; switchboards, protection and motor systems.<\/p>\n      <\/div>\n      <div class=\"mh-eto-diagrams\">\n        <div class=\"mh-eto-diagram\">\n          <img decoding=\"async\" src=\"https:\/\/maritimehub.co.uk\/wp-content\/uploads\/2024\/06\/2019-04-21-10.07.43-scaled.jpg\" alt=\"Main switchboard\" loading=\"lazy\">\n          <div class=\"mh-eto-diagram-cap\">Main switchboard &mdash; where paralleling discipline is tested.<\/div>\n        <\/div>\n        <div class=\"mh-eto-diagram\">\n          <img decoding=\"async\" src=\"https:\/\/maritimehub.co.uk\/wp-content\/uploads\/2024\/06\/2019-04-21-10.07.43-scaled.jpg\" alt=\"MCC panels\" loading=\"lazy\">\n          <div class=\"mh-eto-diagram-cap\">MCC panels &mdash; every starter, every thermal setting, every log.<\/div>\n        <\/div>\n        <div class=\"mh-eto-diagram\">\n          <img decoding=\"async\" src=\"https:\/\/maritimehub.co.uk\/wp-content\/uploads\/2024\/06\/2019-04-21-10.07.43-scaled.jpg\" alt=\"VFD and motor\" loading=\"lazy\">\n          <div class=\"mh-eto-diagram-cap\">Drives &amp; motors &mdash; start behaviour tells you more than a data sheet.<\/div>\n        <\/div>\n      <\/div>\n    <\/section>\n\n    <section class=\"mh-eto-block\" id=\"checklists\">\n      <div class=\"mh-eto-block-head\">\n        <h2>Checklists, SOPs &amp; Test Records<\/h2>\n        <p>The paperwork that actually earns its place in the ETO&#8217;s day &mdash; and holds up in audit.<\/p>\n      <\/div>\n      <div class=\"mh-eto-cards\">\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/calculators-data-sheets\/\">\n          <strong>Calculators &amp; Tools Hub<\/strong>\n          <span>Every ETO calculator and data sheet indexed in one place.<\/span>\n        <\/a>\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/checklists-sops-test-records\/\">\n          <strong>Test Record Bundle<\/strong>\n          <span>Insulation resistance, relay tests, UPS autonomy, thermographic sweep.<\/span>\n        <\/a>\n        <a class=\"mh-eto-card\" href=\"https:\/\/maritimehub.co.uk\/documentation-drawings-compliance\/\">\n          <strong>Drawings &amp; Compliance<\/strong>\n          <span>As-built drawings, class requirements, survey-ready electrical packs.<\/span>\n        <\/a>\n      <\/div>\n    <\/section>\n\n  <\/main>\n\n  <aside class=\"mh-eto-side\">\n    <div class=\"mh-eto-sidebox\">\n      <div class=\"mh-eto-sidebox-header\">Sponsored<\/div>\n      <div class=\"mh-eto-ad-slot\">300 &times; 250 ETO sponsor slot<\/div>\n    <\/div>\n\n    <div class=\"mh-eto-sidebox\">\n      <div class=\"mh-eto-sidebox-header\">Electrical Room Photos<\/div>\n      <figure class=\"mh-eto-gallery-figure\" id=\"mhEtoGalleryWrap\">\n        <img decoding=\"async\" id=\"mhEtoGalleryImg\" src=\"https:\/\/maritimehub.co.uk\/wp-content\/uploads\/2024\/06\/2019-04-21-10.07.43-scaled.jpg\" alt=\"Electrical room photo\" loading=\"lazy\">\n      <\/figure>\n      <div class=\"mh-eto-gallery-controls\">\n        <button class=\"mh-eto-gallery-btn\" id=\"mhEtoGalleryPrev\" type=\"button\">&larr; Prev<\/button>\n        <button class=\"mh-eto-gallery-btn\" id=\"mhEtoGalleryNext\" type=\"button\">Next &rarr;<\/button>\n      <\/div>\n    <\/div>\n\n    <div class=\"mh-eto-sidebox\">\n      <div class=\"mh-eto-sidebox-header\">Latest ETO Posts<\/div>\n      <ul class=\"mh-eto-rail-links\">\n        <li><a href=\"https:\/\/maritimehub.co.uk\/pms-load-sharing-shedding-blackout\/\">Blackout Recovery &amp; PMS Checklist <i>&rarr;<\/i><\/a><\/li>\n        <li><a href=\"https:\/\/maritimehub.co.uk\/safety-loto-arc-flash-hv-work\/\">Arc-Flash &amp; HV Permits <i>&rarr;<\/i><\/a><\/li>\n        <li><a href=\"https:\/\/maritimehub.co.uk\/shore-power-cold-ironing-energy-management\/\">Shore Power on Older Ships <i>&rarr;<\/i><\/a><\/li>\n        <li><a href=\"https:\/\/maritimehub.co.uk\/motors-starters-vfds\/\">VFD Troubleshooting <i>&rarr;<\/i><\/a><\/li>\n        <li><a href=\"https:\/\/maritimehub.co.uk\/power-quality-harmonics\/\">Harmonics &amp; THD Nuisance Trips <i>&rarr;<\/i><\/a><\/li>\n      <\/ul>\n    <\/div>\n\n    <div class=\"mh-eto-sidebox\">\n      <div class=\"mh-eto-sidebox-header\">Sponsored<\/div>\n      <div class=\"mh-eto-ad-slot mh-eto-ad-slot--tall\">300 &times; 600<\/div>\n    <\/div>\n  <\/aside>\n\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Contents ETO &amp; Electrical ETO &amp; Electrical \u00d7 ETO &amp; Electrical Fundamentals, Safety &amp; Distribution\u25be Electrical Principles &amp; Standards Safety: LOTO, Arc-Flash &amp; HV Work HV Power (3.3&ndash;11 kV) LV Distribution Switchboards &amp; MCCs Protection &amp; Coordination Generation, Propulsion &amp; Quality\u25be Generators, AVR &amp; Excitation PMS: Load Sharing, Shedding &amp; Blackout Shore Power \/ Cold [&hellip;]<\/p>\n","protected":false},"author":199,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"c2c-post-author-ip":"","footnotes":""},"class_list":["post-46426","page","type-page","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/maritimehub.co.uk\/?rest_route=\/wp\/v2\/pages\/46426","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/maritimehub.co.uk\/?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/maritimehub.co.uk\/?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/maritimehub.co.uk\/?rest_route=\/wp\/v2\/users\/199"}],"replies":[{"embeddable":true,"href":"https:\/\/maritimehub.co.uk\/?rest_route=%2Fwp%2Fv2%2Fcomments&post=46426"}],"version-history":[{"count":6,"href":"https:\/\/maritimehub.co.uk\/?rest_route=\/wp\/v2\/pages\/46426\/revisions"}],"predecessor-version":[{"id":52504,"href":"https:\/\/maritimehub.co.uk\/?rest_route=\/wp\/v2\/pages\/46426\/revisions\/52504"}],"wp:attachment":[{"href":"https:\/\/maritimehub.co.uk\/?rest_route=%2Fwp%2Fv2%2Fmedia&parent=46426"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}