{"id":2861,"date":"2026-08-26T09:18:00","date_gmt":"2026-08-26T09:18:00","guid":{"rendered":"https:\/\/lbajiele.com\/?p=2861"},"modified":"2026-08-25T12:09:58","modified_gmt":"2026-08-25T12:09:58","slug":"air-insulated-medium-voltage-switchgear-guide","status":"publish","type":"post","link":"https:\/\/lbajiele.com\/vi\/blog\/air-insulated-medium-voltage-switchgear-guide\/","title":{"rendered":"T\u1ee7 \u0111i\u1ec7n trung th\u1ebf c\u00e1ch \u0111i\u1ec7n b\u1eb1ng kh\u00f4ng kh\u00ed: Thi\u1ebft k\u1ebf &amp; L\u1ef1a ch\u1ecdn"},"content":{"rendered":"<p><strong>Air-insulated medium-voltage switchgear uses atmospheric air as the principal insulation between phases and ground while metal compartments contain breakers, buses, instrument transformers, cables and control equipment.<\/strong> AIS is maintainable and familiar but requires more space than sealed alternatives. Selection should be based on rated voltage, insulation level, continuous and short-circuit current, internal-arc strategy, service continuity, environment and maintenance access.<\/p>\n<div class=\"lbaji-key-takeaways\"><h2>Nh\u1eefng \u0111i\u1ec3m ch\u00ednh<\/h2><ul><li>Do not select MV switchgear from nominal voltage alone.<\/li><li>Compartmentalization, interlocks and arc classification affect personnel risk and continuity.<\/li><li>Altitude, contamination, condensation and access can change the correct design.<\/li><\/ul><\/div>\n<h2>AIS Construction and Compartments<\/h2><figure class=\"wp-block-image size-large\"><img decoding=\"async\" alt=\"Air-insulated switchgear compartments\" loading=\"lazy\" src=\"https:\/\/lbajiele.com\/wp-content\/uploads\/2026\/08\/air-insulated-switchgear-compartments.png\"\/><figcaption>Air-insulated switchgear compartments.<\/figcaption><\/figure>\n<p>A typical metal-clad lineup separates the drawout circuit breaker, main bus, cable terminations and low-voltage controls with grounded metal barriers. Shutters cover primary disconnects when the breaker is withdrawn. Current and voltage transformers supply metering and relays, while grounding switches or trucks support maintenance where specified.<\/p>\n<p>Metal-enclosed switchgear is a broader term and may provide less segregation than metal-clad construction. The project specification should state the construction standard and service requirements instead of relying on marketing names.<\/p>\n<h2>Electrical Ratings That Control Selection<\/h2>\n<p>Rated maximum voltage and power-frequency or impulse withstand must suit the system and insulation coordination. Continuous current applies to the bus and each functional unit. Short-time withstand current and duration describe thermal duty; peak withstand describes electrodynamic force. Breaker interrupting and closing ratings must exceed the studied fault duty.<\/p>\n<p>Frequency, grounding, load type, cable charging, capacitor switching, transformer inrush and motor duty may affect breaker selection. Future fault-level growth should be evaluated rather than hidden by rounding.<\/p>\n<h2>Internal Arc, Interlocks and Service Continuity<\/h2><figure class=\"wp-block-image size-large\"><img decoding=\"async\" alt=\"Medium-voltage switchgear factory testing\" loading=\"lazy\" src=\"https:\/\/lbajiele.com\/wp-content\/uploads\/2026\/08\/mv-switchgear-factory-testing.png\"\/><figcaption>Medium-voltage switchgear factory testing.<\/figcaption><\/figure>\n<p>An internal-arc classification states tested accessibility sides, arc current and duration under defined conditions. It is not a guarantee that every possible arc event is harmless. Room relief paths, exhaust ducts, fastening, installation and maintenance condition must match the tested configuration.<\/p>\n<p>Mechanical and electrical interlocks should prevent unsafe operations such as racking a closed breaker, accessing energized compartments or closing onto an improperly positioned earthing switch. Key interlocks must be documented across connected equipment.<\/p>\n<h2>AIS Rating and Construction Checklist<\/h2><figure class=\"wp-block-table is-style-stripes\"><table><thead><tr><th scope=\"col\">M\u1ee5c<\/th><th scope=\"col\">Specify<\/th><th scope=\"col\">Common mistake<\/th><th scope=\"col\">X\u00e1c minh<\/th><\/tr><\/thead><tbody><tr><td>Voltage insulation<\/td><td>Maximum voltage, BIL\/LIWV and power-frequency withstand<\/td><td>Using nominal voltage only<\/td><td>Nameplate and dielectric report<\/td><\/tr><tr><td>D\u00f2ng c\u1eaft s\u1ef1 c\u1ed1<\/td><td>Short-time, peak, breaker interrupting and duration<\/td><td>Ignoring future fault growth<\/td><td>Short-circuit study and test certificates<\/td><\/tr><tr><td>Arc performance<\/td><td>Accessibility, current, duration and exhaust arrangement<\/td><td>Treating arc-resistant as universal<\/td><td>Classification report and room design<\/td><\/tr><tr><td>Compartments<\/td><td>Breaker, bus, cable and LV segregation<\/td><td>Assuming all metal-enclosed gear is metal-clad<\/td><td>Construction drawings<\/td><\/tr><tr><td>M\u00f4i tr\u01b0\u1eddng<\/td><td>Altitude, pollution, humidity and temperature<\/td><td>No condensation control<\/td><td>Site data and manufacturer derating<\/td><\/tr><\/tbody><\/table><\/figure>\n<h2>Environment, Maintenance and Factory Tests<\/h2>\n<p>Dust, salt, humidity, condensation, altitude and temperature affect insulation and corrosion. Space heaters, ventilation, filtered rooms or higher creepage may be necessary. Altitude can require insulation or current derating depending on the standard and equipment design.<\/p>\n<p>Routine maintenance includes cleaning, mechanical operation, contact inspection, insulation checks, relay testing and verification of racking and shutters. Factory acceptance should cover dielectric, resistance, mechanical, wiring, protection and functional tests with traceable records.<\/p>\n<h2>X\u00e1c th\u1ef1c k\u1ef9 thu\u1eadt v\u00e0 Gi\u1edbi h\u1ea1n an to\u00e0n<\/h2><p>H\u01b0\u1edbng d\u1eabn n\u00e0y h\u1ed7 tr\u1ee3 vi\u1ec7c l\u1eadp th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt v\u00e0 mua s\u1eafm; t\u00e0i li\u1ec7u n\u00e0y kh\u00f4ng thay th\u1ebf cho nghi\u00ean c\u1ee9u d\u1ef1 \u00e1n, quy chu\u1ea9n hi\u1ec7n h\u00e0nh, h\u01b0\u1edbng d\u1eabn c\u1ee7a nh\u00e0 s\u1ea3n xu\u1ea5t ho\u1eb7c c\u00f4ng vi\u1ec7c c\u1ee7a nh\u00e2n vi\u00ean \u0111i\u1ec7n c\u00f3 chuy\u00ean m\u00f4n. H\u00e3y x\u00e1c minh c\u00e1c n\u1ed9i dung sau tr\u01b0\u1edbc khi l\u1ef1a ch\u1ecdn thi\u1ebft b\u1ecb, th\u1eed nghi\u1ec7m, \u0111\u1ea5u d\u00e2y ho\u1eb7c \u0111\u00f3ng \u0111i\u1ec7n:<\/p><ul><li>Use the latest short-circuit, load-flow and protection studies.<\/li><li>Confirm cable termination space, bend radius, phase sequence and entry direction.<\/li><li>Coordinate room clearances, pressure relief and emergency egress.<\/li><li>Verify interlocks through a documented functional sequence.<\/li><li>Keep doors, covers and fasteners in the tested condition during service.<\/li><\/ul>\n<h2>Th\u00f4ng tin c\u1ea7n \u0111\u01b0a v\u00e0o Y\u00eau c\u1ea7u b\u00e1o gi\u00e1<\/h2><p>M\u1ed9t b\u00e1o gi\u00e1 h\u1eefu \u00edch ph\u1ea3i d\u1ef1a tr\u00ean c\u00f9ng m\u1ed9t ranh gi\u1edbi k\u1ef9 thu\u1eadt cho m\u1ecdi nh\u00e0 cung c\u1ea5p. H\u00e3y bao g\u1ed3m c\u00e1c th\u00f4ng tin sau v\u00e0 y\u00eau c\u1ea7u li\u1ec7t k\u00ea r\u00f5 r\u00e0ng m\u1ecdi sai l\u1ec7ch:<\/p><ul><li>System voltage, frequency, grounding and available fault current.<\/li><li>Bus and feeder currents, breaker duties and protection functions.<\/li><li>Construction standard, compartment class and internal-arc requirement.<\/li><li>Indoor\/outdoor environment, altitude, temperature and corrosion exposure.<\/li><li>Single-line, lineup, cable schedule, communication, tests and documentation.<\/li><\/ul>\n<h2>T\u1eeb D\u1eef li\u1ec7u K\u1ef9 thu\u1eadt \u0111\u1ebfn m\u1ed9t Quy\u1ebft \u0111\u1ecbnh \u0111\u01b0\u1ee3c Ph\u00ea duy\u1ec7t<\/h2><p>Use a staged review rather than approving the first catalogue match. Begin with ais construction and compartments, then reconcile electrical ratings that control selection with internal arc, interlocks and service continuity. Complete the review with environment, maintenance and factory tests. At each stage, record the source document, units, operating case and person responsible for approval. This prevents a value copied from an old drawing, nominal system label or unrelated product from becoming an uncontrolled design input.<\/p><p>Tr\u01b0\u1edbc khi nghi\u1ec7m thu, h\u00e3y so s\u00e1nh ph\u1ea3n h\u1ed3i c\u1ee7a nh\u00e0 th\u1ea7u t\u1eebng d\u00f2ng m\u1ed9t v\u1edbi Y\u00eau c\u1ea7u b\u00e1o gi\u00e1 (RFQ) v\u00e0 \u0111\u00e1nh d\u1ea5u m\u1ecdi \u0111i\u1ec3m ngo\u1ea1i l\u1ec7. X\u00e1c nh\u1eadn r\u1eb1ng c\u00e1c b\u1ea3n v\u1ebd, t\u00ednh to\u00e1n, th\u00f4ng s\u1ed1 c\u00e0i \u0111\u1eb7t, ch\u1ee9ng ch\u1ec9 v\u00e0 b\u00e1o c\u00e1o th\u1eed nghi\u1ec7m \u0111\u1ec1u \u0111\u1ec1 c\u1eadp ch\u00ednh x\u00e1c \u0111\u1ebfn m\u1eabu v\u00e0 phi\u00ean b\u1ea3n \u0111\u01b0\u1ee3c ch\u00e0o th\u1ea7u. L\u01b0u gi\u1eef h\u1ed3 s\u01a1 tr\u00ecnh duy\u1ec7t \u0111\u00e3 \u0111\u01b0\u1ee3c ph\u00ea duy\u1ec7t, d\u1eef li\u1ec7u tr\u00ean nh\u00e3n thi\u1ebft b\u1ecb, k\u1ebft qu\u1ea3 th\u1eed nghi\u1ec7m t\u1ea1i x\u01b0\u1edfng v\u00e0 c\u00e1c th\u00f4ng s\u1ed1 \u0111o \u0111\u1ea1c khi ch\u1ea1y th\u1eed l\u00e0m c\u01a1 s\u1edf b\u1ea3o tr\u00ec. N\u1ebfu c\u00f3 s\u1ef1 thay \u0111\u1ed5i v\u1ec1 \u0111\u1ecbnh m\u1ee9c, k\u1ebft n\u1ed1i, m\u00f4i tr\u01b0\u1eddng ho\u1eb7c \u0111i\u1ec1u ki\u1ec7n th\u1eed nghi\u1ec7m, h\u00e3y l\u1eb7p l\u1ea1i vi\u1ec7c \u0111\u00e1nh gi\u00e1 \u0111\u1ed1i v\u1edbi ph\u1ea7n b\u1ecb \u1ea3nh h\u01b0\u1edfng thay v\u00ec gi\u1ea3 \u0111\u1ecbnh r\u1eb1ng k\u1ebft lu\u1eadn ban \u0111\u1ea7u v\u1eabn c\u00f2n gi\u00e1 tr\u1ecb.<\/p>\n<p>Vi\u1ec7c ki\u1ec3m so\u00e1t t\u00e0i li\u1ec7u ph\u1ea3i x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c phi\u00ean b\u1ea3n, tr\u1ea1ng th\u00e1i ph\u00ea duy\u1ec7t v\u00e0 c\u00e1c t\u1ec7p b\u1ecb thay th\u1ebf. C\u00e1c \u0111\u1ed9i ng\u0169 hi\u1ec7n tr\u01b0\u1eddng ph\u1ea3i nh\u1eadn \u0111\u01b0\u1ee3c c\u00e1c gi\u00e1 tr\u1ecb \u0111\u00e3 \u0111\u01b0\u1ee3c ph\u00ea duy\u1ec7t gi\u1ed1ng nhau \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng cho vi\u1ec7c mua s\u1eafm, trong khi c\u00e1c h\u1ed3 s\u01a1 ch\u1ea1y th\u1eed ph\u1ea3i ghi l\u1ea1i m\u1ecdi thay \u0111\u1ed5i \u0111\u01b0\u1ee3c \u1ee7y quy\u1ec1n th\u1ef1c hi\u1ec7n trong qu\u00e1 tr\u00ecnh l\u1eafp \u0111\u1eb7t. Kh\u1ea3 n\u0103ng truy xu\u1ea5t ngu\u1ed3n g\u1ed1c n\u00e0y \u0111\u1eb7c bi\u1ec7t quan tr\u1ecdng khi thi\u1ebft b\u1ecb \u0111\u01b0\u1ee3c thay th\u1ebf nhi\u1ec1u n\u0103m sau \u0111\u00f3: k\u1ef9 s\u01b0 ti\u1ebfp theo c\u1ea7n c\u00e1c giao di\u1ec7n \u0111\u00e3 \u0111\u01b0\u1ee3c x\u00e1c minh v\u00e0 l\u1ecbch s\u1eed ki\u1ec3m tra, ch\u1ee9 kh\u00f4ng ph\u1ea3i l\u00e0 m\u1ed9t m\u00f4 t\u1ea3 ch\u01b0a \u0111\u1ea7y \u0111\u1ee7 \u0111\u01b0\u1ee3c sao ch\u00e9p t\u1eeb \u0111\u01a1n \u0111\u1eb7t h\u00e0ng.<\/p>\n<h2>Th\u00f4ng tin bao qu\u00e1t d\u1ef1a tr\u00ean k\u1ebft qu\u1ea3 t\u00ecm ki\u1ebfm hi\u1ec7n t\u1ea1i<\/h2><p>The current U.S. Google top-20 review repeatedly surfaced themes including AIR-INSULATED SWITCHGEAR, Gas-insulated switchgear (GIS) portfolio, What is Medium Voltage Switchgear?, RELATED OFFERING, Live Tank Circuit Breakers (LTB). The article addresses those user needs in an original engineering and procurement sequence; competitor brand navigation and unrelated sales material were excluded.<\/p>\n<h2>T\u00e0i li\u1ec7u LBAJI li\u00ean quan<\/h2><p>Ti\u1ebfp t\u1ee5c v\u1edbi <a href=\"https:\/\/lbajiele.com\/vi\/blog\/complete-guide-to-medium-voltage-switchgear\/\">h\u01b0\u1edbng d\u1eabn thi\u1ebft b\u1ecb \u0111\u00f3ng c\u1eaft trung th\u1ebf<\/a> <a href=\"https:\/\/lbajiele.com\/vi\/blog\/complete-guide-to-gas-air-insulated-switchgear\/\">gas versus air-insulated switchgear<\/a> <a href=\"https:\/\/lbajiele.com\/vi\/danh-muc-san-pham\/switchgear\/\">LBAJI switchgear products<\/a>. Nh\u1eefng t\u00e0i nguy\u00ean n\u00e0y gi\u00fap k\u1ebft n\u1ed1i vi\u1ec7c t\u00ednh to\u00e1n ho\u1eb7c quy\u1ebft \u0111\u1ecbnh l\u1ef1a ch\u1ecdn linh ki\u1ec7n v\u1edbi m\u1ed9t b\u1ea3ng th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt ho\u00e0n ch\u1ec9nh c\u1ee7a m\u00e1y bi\u1ebfn \u00e1p, thi\u1ebft b\u1ecb \u0111\u00f3ng c\u1eaft, thi\u1ebft b\u1ecb \u0111i\u1ec1u khi\u1ec3n ho\u1eb7c thi\u1ebft b\u1ecb ph\u00e2n ph\u1ed1i.<\/p>\n<div id=\"rank-math-faq\" class=\"rank-math-block\">\n<div class=\"rank-math-list\">\n<\/div>\n<\/div>\n<section class=\"lbaji-technical-references\"><h2>T\u00e0i li\u1ec7u tham kh\u1ea3o k\u1ef9 thu\u1eadt v\u00e0 \u0110\u1ecdc th\u00eam<\/h2><ul><li><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/67180\" rel=\"noopener noreferrer nofollow\" target=\"_blank\">IEC 62271-200<\/a> \u2014 AC metal-enclosed switchgear and internal-arc classification.<\/li><li><a href=\"https:\/\/standards.ieee.org\/\" rel=\"noopener noreferrer nofollow\" target=\"_blank\">Hi\u1ec7p h\u1ed9i Ti\u00eau chu\u1ea9n IEEE<\/a> \u2014 C37 switchgear and circuit-breaker standards.<\/li><li><a href=\"https:\/\/www.osha.gov\/electrical\" rel=\"noopener noreferrer nofollow\" target=\"_blank\">An to\u00e0n \u0111i\u1ec7n OSHA<\/a> \u2014 Work practices around electrical equipment.<\/li><\/ul><\/section>\n<h2>K\u1ebft lu\u1eadn<\/h2><p>A sound AIS specification joins electrical ratings, compartment construction, arc strategy, site environment and maintainability. Require the supplier to demonstrate each rating and interface with drawings and test evidence rather than a catalogue description.<\/p>","protected":false},"excerpt":{"rendered":"<p>T\u1ee7 \u0111i\u1ec7n trung th\u1ebf c\u00e1ch \u0111i\u1ec7n b\u1eb1ng kh\u00f4ng kh\u00ed s\u1eed d\u1ee5ng kh\u00f4ng kh\u00ed kh\u00ed quy\u1ec3n l\u00e0m l\u1edbp c\u00e1ch \u0111i\u1ec7n ch\u00ednh gi\u1eefa c\u00e1c pha v\u00e0 n\u1ed1i \u0111\u1ea5t, trong khi c\u00e1c khoang kim lo\u1ea1i ch\u1ee9a m\u00e1y c\u1eaft, thanh d\u1eabn \u0111i\u1ec7n, m\u00e1y bi\u1ebfn d\u00f2ng\/\u0111i\u1ec7n \u00e1p \u0111o l\u01b0\u1eddng, c\u00e1p v\u00e0 thi\u1ebft b\u1ecb \u0111i\u1ec1u khi\u1ec3n.<\/p>","protected":false},"author":6,"featured_media":2860,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[53],"tags":[76,75,72,69],"class_list":["post-2861","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-switchgear-protection","tag-medium-voltage-switchgear","tag-switchgear","tag-transformer-components","tag-transformer-protection"],"blocksy_meta":[],"acf":[],"_links":{"self":[{"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/posts\/2861","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/comments?post=2861"}],"version-history":[{"count":1,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/posts\/2861\/revisions"}],"predecessor-version":[{"id":3008,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/posts\/2861\/revisions\/3008"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/media\/2860"}],"wp:attachment":[{"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/media?parent=2861"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/categories?post=2861"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/tags?post=2861"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}