{"id":2154,"date":"2025-08-13T17:13:07","date_gmt":"2025-08-13T09:13:07","guid":{"rendered":"https:\/\/www.britecelectric.com\/?post_type=blog&#038;p=2154"},"modified":"2025-08-13T17:13:07","modified_gmt":"2025-08-13T09:13:07","slug":"what-is-a-type-2-surge-protection-device","status":"publish","type":"blog","link":"https:\/\/www.britecelectric.com\/da\/blog\/what-is-a-type-2-surge-protection-device\/","title":{"rendered":"Hvad er en type 2 oversp\u00e6ndingsbeskyttelsesenhed?"},"content":{"rendered":"<h2 data-start=\"226\" data-end=\"241\">Indledning<\/h2>\r\n<p data-start=\"243\" data-end=\"597\">A <a href=\"https:\/\/www.britecelectric.com\/da\/product-category\/ac-power-surge-protection\/type-2-surge-protective-device\/\"><strong data-start=\"245\" data-end=\"279\">Type 2 oversp\u00e6ndingsbeskyttelsesenhed<\/strong><\/a> (Type 2 SPD) er rygraden i oversp\u00e6ndingsbeskyttelse i moderne elektriske systemer. Installeret p\u00e5 hovedfordelingstavlen eller kontrolskabet fungerer det som det andet skjold i en lagdelt forsvarsstrategi - fanger resterende oversp\u00e6ndinger efterladt af opstr\u00f8ms Type 1 SPD'er og undertrykker transienter genereret inde i netv\u00e6rket.<\/p>\r\n<p data-start=\"599\" data-end=\"986\">Disse enheder beskytter mod 8\/20 \u03bcs impulsstr\u00f8mme, der opst\u00e5r fra lyn-inducerede oversp\u00e6ndinger, koblingsh\u00e6ndelser eller forsyningsforstyrrelser.<\/p>\r\nFor at sikre p\u00e5lidelig, langsigtet beskyttelse skal ingeni\u00f8rer og tekniske k\u00f8bere forst\u00e5 flere n\u00f8gleaspekter af en Type 2 SPD:\r\n<ul>\r\n \t<li><b>Definition:<\/b> Hvad er det?<\/li>\r\n \t<li><b>S\u00e5dan fungerer det:<\/b> Dens driftsprincipper.<\/li>\r\n \t<li><b>Standarder:<\/b> Hvilke regler opfylder det?<\/li>\r\n \t<li><b>Installation og valg:<\/b> Reglerne for at v\u00e6lge og installere det korrekt.<\/li>\r\n<\/ul>\r\n<h2 data-start=\"993\" data-end=\"1042\">Definition af en type 2 oversp\u00e6ndingsbeskyttelsesenhed<\/h2>\r\n<p data-start=\"1044\" data-end=\"1268\">If\u00f8lge <a href=\"https:\/\/webstore.iec.ch\/en\/publication\/65314\" target=\"_blank\" rel=\"noopener\"><em><strong>IEC\/EN 61643-11 standard<\/strong><\/em><\/a>, en **Type 2 SPD** er en klasse II-enhed. Den er designet til steder, der ikke har direkte lynnedslag. Disse steder st\u00e5r dog stadig over for en risiko for kraftige forbig\u00e5ende oversp\u00e6ndinger.<\/p>\r\n<p data-start=\"1270\" data-end=\"1290\">N\u00f8glekarakteristika:<\/p>\r\n\r\n<ul data-start=\"1291\" data-end=\"1618\">\r\n \t<li data-start=\"1291\" data-end=\"1335\">\r\n<p data-start=\"1293\" data-end=\"1335\">Testet med 8\/20 \u03bcs str\u00f8mb\u00f8lgeformer.<\/p>\r\n<\/li>\r\n \t<li data-start=\"1336\" data-end=\"1466\">\r\n<p data-start=\"1338\" data-end=\"1466\">Typisk nominel afladningsstr\u00f8m (In) er mellem 5\u201320 kA, med maksimal afladningsstr\u00f8m (Imax) op til 40\u201380 kA.<\/p>\r\n<\/li>\r\n \t<li data-start=\"1467\" data-end=\"1530\">\r\n<p data-start=\"1469\" data-end=\"1530\">Monteret p\u00e5 lastsiden af \u200b\u200bdet elektriske servicepanel.<\/p>\r\n<\/li>\r\n \t<li data-start=\"1531\" data-end=\"1618\">\r\n<p data-start=\"1533\" data-end=\"1618\">Beskytter mod b\u00e5de eksterne restoversp\u00e6ndinger og interne koblingsoversp\u00e6ndinger.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"1620\" data-end=\"1802\">I praktisk anvendelse sidder en Type 2 SPD efter en Type 1 enhed og f\u00f8r enhver downstream Type 3 point-of-use beskyttelse, der udg\u00f8r en del af et flertrins oversp\u00e6ndingsbeskyttelsessystem.<\/p>\r\n<p data-start=\"1620\" data-end=\"1802\"><a href=\"https:\/\/www.britecelectric.com\/da\/product-category\/ac-power-surge-protection\/type-2-surge-protective-device\/\" target=\"_blank\" rel=\"noopener\"><img class=\"alignnone  wp-image-2160\" src=\"https:\/\/www.britecelectric.com\/wp-content\/uploads\/2025\/08\/BR-20-4P-1Type-2-Surge-Protection-Device.jpg-1024x1024.webp\" alt=\"\" width=\"900\" height=\"900\" \/><\/a><\/p>\r\n\r\n<h2 data-start=\"1809\" data-end=\"1859\">Hvordan virker en <a href=\"https:\/\/www.britecelectric.com\/da\/product-category\/ac-power-surge-protection\/type-2-surge-protective-device\/\" target=\"_blank\" rel=\"noopener\">Type 2 oversp\u00e6ndingsbeskyttelsesenhed<\/a> arbejde?<\/h2>\r\n<p data-start=\"1861\" data-end=\"2143\">En Type 2 SPD fungerer efter sp\u00e6ndingssp\u00e6ndingsprincippet. Under normal sp\u00e6nding forbliver den passiv. N\u00e5r en transient oversp\u00e6nding overstiger dens maksimale kontinuerlige driftssp\u00e6nding (Uc), skifter dens interne komponenter hurtigt til en ledende tilstand, hvilket shunter overskydende energi til jorden.<\/p>\r\n<p data-start=\"2145\" data-end=\"2176\"><strong data-start=\"2145\" data-end=\"2176\">Typiske komponenter omfatter:<\/strong><\/p>\r\n\r\n<ul data-start=\"2177\" data-end=\"2557\">\r\n \t<li data-start=\"2177\" data-end=\"2285\">\r\n<p data-start=\"2179\" data-end=\"2285\"><strong data-start=\"2179\" data-end=\"2210\">MOV (metaloxidvaristor):<\/strong> Det prim\u00e6re sp\u00e6ndeelement, der absorberer oversp\u00e6ndingsenergi og reducerer sp\u00e6ndingen.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2286\" data-end=\"2385\">\r\n<p data-start=\"2288\" data-end=\"2385\"><strong data-start=\"2288\" data-end=\"2320\">Hybridkredsl\u00f8b (MOV + GDT):<\/strong> Kombiner h\u00f8j oversp\u00e6ndingskapacitet med forbedret langsigtet p\u00e5lidelighed.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2386\" data-end=\"2470\">\r\n<p data-start=\"2388\" data-end=\"2470\"><strong data-start=\"2388\" data-end=\"2418\">Termisk afbrydelsessystem:<\/strong> Isolerer SPD'en ved endt levetid for at opretholde sikkerheden.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2471\" data-end=\"2557\">\r\n<p data-start=\"2473\" data-end=\"2557\"><strong data-start=\"2473\" data-end=\"2494\">Statusindikator:<\/strong> Visuelt vindue eller kontaktoutput for at vise driftstilstand.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"2559\" data-end=\"2582\"><strong data-start=\"2559\" data-end=\"2582\">Betjeningssekvens:<\/strong><\/p>\r\n\r\n<ol data-start=\"2583\" data-end=\"2882\">\r\n \t<li data-start=\"2583\" data-end=\"2645\">\r\n<p data-start=\"2586\" data-end=\"2645\"><strong data-start=\"2586\" data-end=\"2602\">Normal tilstand:<\/strong> H\u00f8j modstand, ingen indvirkning p\u00e5 kredsl\u00f8bet.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2646\" data-end=\"2699\">\r\n<p data-start=\"2649\" data-end=\"2699\"><strong data-start=\"2649\" data-end=\"2665\">Oversp\u00e6ndingsh\u00e6ndelse:<\/strong> Sp\u00e6ndingen stiger over Uc-t\u00e6rsklen.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2700\" data-end=\"2819\">\r\n<p data-start=\"2703\" data-end=\"2819\"><strong data-start=\"2703\" data-end=\"2716\">Fastsp\u00e6nding:<\/strong> SPD afleder oversp\u00e6ndingsstr\u00f8mmen til jord, hvilket s\u00e6nker sp\u00e6ndingen til en sikker op (sp\u00e6ndingsbeskyttelsesniveau).<\/p>\r\n<\/li>\r\n \t<li data-start=\"2820\" data-end=\"2882\">\r\n<p data-start=\"2823\" data-end=\"2882\"><strong data-start=\"2823\" data-end=\"2836\">Gendannelse:<\/strong> SPD vender tilbage til standbytilstand med h\u00f8j modstand.<\/p>\r\n<\/li>\r\n<\/ol>\r\n<h2 data-start=\"2889\" data-end=\"2940\">Funktionen af \u200b\u200ben type 2 oversp\u00e6ndingsbeskyttelsesenhed<\/h2>\r\n<p data-start=\"2942\" data-end=\"3106\">Den prim\u00e6re rolle for en oversp\u00e6ndingsbeskyttelsesanordning Type 2 er at begr\u00e6nse transiente oversp\u00e6ndinger til et niveau, som downstream-udstyr kan modst\u00e5 uden skader.<\/p>\r\n<p data-start=\"3108\" data-end=\"3122\">N\u00f8glefunktioner:<\/p>\r\n\r\n<ul data-start=\"3123\" data-end=\"3659\">\r\n \t<li data-start=\"3123\" data-end=\"3228\">\r\n<p data-start=\"3125\" data-end=\"3228\"><strong data-start=\"3125\" data-end=\"3154\">Restoversp\u00e6ndingsbegr\u00e6nsning<\/strong> \u2014 reducerer sp\u00e6ndingen, efter at en Type 1 SPD har absorberet hovedparten af \u200b\u200benergien.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3229\" data-end=\"3356\">\r\n<p data-start=\"3231\" data-end=\"3356\"><strong data-start=\"3231\" data-end=\"3262\">Skiftende oversp\u00e6ndingsundertrykkelse<\/strong> \u2014 d\u00e6mper transienter fra motorstarter, pumpeskift eller andre induktive belastningsoperationer.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3357\" data-end=\"3471\">\r\n<p data-start=\"3359\" data-end=\"3471\"><strong data-start=\"3359\" data-end=\"3383\">Beskyttelse af udstyr<\/strong> \u2014 forhindrer skader p\u00e5 f\u00f8lsom elektronik, PLC'er, automatiseringssystemer og styreudstyr.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3472\" data-end=\"3544\">\r\n<p data-start=\"3474\" data-end=\"3544\"><strong data-start=\"3474\" data-end=\"3496\">Systemp\u00e5lidelighed<\/strong> \u2014 reducerer nedetid fra oversp\u00e6ndingsrelaterede fejl.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3545\" data-end=\"3659\">\r\n<p data-start=\"3547\" data-end=\"3659\"><strong data-start=\"3547\" data-end=\"3568\">En del af en kaskade<\/strong> \u2014 sidder mellem serviceindgangsbeskyttelsen (Type 1) og punkt-of-use enheder (Type 3).<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"3666\" data-end=\"3716\">Anvendelser af type 2 oversp\u00e6ndingsbeskyttelsesanordninger<\/h2>\r\n<a href=\"https:\/\/www.britecelectric.com\/da\/attachment\/spd-install\/\" rel=\"attachment wp-att-2159\"><img class=\"alignnone size-full wp-image-2159\" src=\"https:\/\/www.britecelectric.com\/wp-content\/uploads\/2025\/08\/SPD-install.jpg\" alt=\"\" width=\"745\" height=\"609\" \/><\/a>\r\n<p data-start=\"3718\" data-end=\"3747\">Type 2 SPD'er er installeret i:<\/p>\r\n\r\n<ul data-start=\"3748\" data-end=\"4151\">\r\n \t<li data-start=\"3748\" data-end=\"3810\">\r\n<p data-start=\"3750\" data-end=\"3810\">Industrianl\u00e6g med lynbeskyttelsessystemer.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3811\" data-end=\"3891\">\r\n<p data-start=\"3813\" data-end=\"3891\">Kommercielle bygninger til beskyttelse af HVAC, elevatorer, belysning og it-systemer.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3892\" data-end=\"3949\">\r\n<p data-start=\"3894\" data-end=\"3949\">Maskinstyreskabe til industriel automation.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3950\" data-end=\"4034\">\r\n<p data-start=\"3952\" data-end=\"4034\">Vedvarende energisystemer - s\u00e5som solcelle-PV-invertere og vindm\u00f8llestyringer - kr\u00e6ver robuste <a href=\"https:\/\/www.britecelectric.com\/da\/product_category\/pv-surge-protection-type-2\/\" target=\"_blank\" rel=\"noopener\">oversp\u00e6ndingsbeskyttelse<\/a> (se vores <strong><em><a class=\"\" href=\"https:\/\/www.britecelectric.com\/da\/blog\/solar-surge-protection-devices-selection-guide\/\" target=\"_blank\" rel=\"noopener\" data-start=\"201\" data-end=\"334\">Vejledning til valg af soloversp\u00e6ndingsbeskyttelsesenheder<\/a><\/em><\/strong> og <strong><em><a class=\"\" href=\"https:\/\/www.britecelectric.com\/da\/blog\/surge-protection-for-solar-photovoltaic-systems\/\" target=\"_blank\" rel=\"noopener\" data-start=\"339\" data-end=\"474\">Oversp\u00e6ndingsbeskyttelse for solcelleanl\u00e6g<\/a><\/em><\/strong>).<\/p>\r\n<\/li>\r\n \t<li data-start=\"4035\" data-end=\"4093\">\r\n<p data-start=\"4037\" data-end=\"4093\">Hospitaler og datacentre, hvor oppetiden er kritisk.<\/p>\r\n<\/li>\r\n \t<li data-start=\"4094\" data-end=\"4151\">\r\n<p data-start=\"4096\" data-end=\"4151\">Hovedpaneler til boliger til beskyttelse af hele huset.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"262\" data-end=\"316\">Type 1, Type 2 og Type 3 Oversp\u00e6ndingsbeskyttelsesenheder<\/h2>\r\n<p data-start=\"318\" data-end=\"648\">Oversp\u00e6ndingsbeskyttelsesanordninger har tre hovedtyper. Hver type har sit eget arbejde i det elektriske system. Du kan l\u00e6se mere i vores udf\u00f8rlige guide her: <em><strong><a class=\"\" href=\"https:\/\/www.britecelectric.com\/da\/blog\/difference-between-type-1-type-2-and-type-3-surge-protective-devices\/\" target=\"_blank\" rel=\"noopener\" data-start=\"468\" data-end=\"647\">Forskellen mellem type 1, type 2 og type 3 oversp\u00e6ndingsbeskyttelsesanordninger<\/a>.<\/strong><\/em><\/p>\r\n\r\n<table style=\"width: 60.5183%;\">\r\n<tbody>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\"><strong><b>Feature<\/b><\/strong><\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\"><strong><b>Type 1 SPD<\/b><\/strong><\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\"><strong><b>Type 2 SPD<\/b><\/strong><\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\"><strong><b>Type 3 SPD<\/b><\/strong><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Beliggenhed<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">Installeret ved serviceindgangen.<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">Installeret ved hovedfordelingstavlen.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">Installeret t\u00e6t p\u00e5 f\u00f8lsomme belastninger.<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Test b\u00f8lgeform<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">Testet med 10\/350 \u03bcs lynimpuls.<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">Testet med 8\/20 \u03bcs oversp\u00e6ndingsstr\u00f8m.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">Testet med 1,2\/50 \u03bcs sp\u00e6nding + 8\/20 \u03bcs str\u00f8m.<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Form\u00e5l<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">Aflader direkte lynstr\u00f8m.<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">Begr\u00e6nser resterende oversp\u00e6ndinger og koblingsoversp\u00e6ndinger.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">Giver endelig beskyttelse til elektronik.<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Typisk op<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">\u2264 4 kV.<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">\u2264 2,5 kV.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">\u2264 1,5 kV.<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Eksempler<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">Bygninger med et lynbeskyttelsessystem (LPS).<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">Kontrolpaneler og underfordelingstavler.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">IT-udstyr og hjemmeelektronik.<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<p data-start=\"1409\" data-end=\"1423\"><strong data-start=\"1409\" data-end=\"1421\">Oversigt:<\/strong><\/p>\r\n\r\n<ul data-start=\"1424\" data-end=\"1706\">\r\n \t<li data-start=\"1424\" data-end=\"1494\">\r\n<p data-start=\"1426\" data-end=\"1494\"><strong data-start=\"1426\" data-end=\"1440\">Type 1 SPD<\/strong> stopper det meste af h\u00f8jenergib\u00f8lgen fra lyn.<\/p>\r\n<\/li>\r\n \t<li data-start=\"1495\" data-end=\"1610\">\r\n<p data-start=\"1497\" data-end=\"1610\"><strong data-start=\"1497\" data-end=\"1511\">Type 2 SPD<\/strong> er midterforsvaret. Det reducerer den resterende oversp\u00e6ndingssp\u00e6nding og styrer koblingsoversp\u00e6ndingen.<\/p>\r\n<\/li>\r\n \t<li data-start=\"1611\" data-end=\"1706\">\r\n<p data-start=\"1613\" data-end=\"1706\"><strong data-start=\"1613\" data-end=\"1627\">Type 3 SPD<\/strong> er det sidste skridt. Det beskytter f\u00f8lsom elektronik mod sm\u00e5, hurtige oversp\u00e6ndinger.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"4715\" data-end=\"4766\">Hvordan v\u00e6lger man den rigtige oversp\u00e6ndingsbeskyttelsesanordning?<\/h2>\r\n<p data-start=\"4768\" data-end=\"4922\">N\u00e5r du v\u00e6lger den bedste type 2-oversp\u00e6ndingsbeskyttelsesenhed, b\u00f8r valget v\u00e6re baseret p\u00e5 systemkompatibilitet, oversp\u00e6ndingsrisikoniveau og udstyrsf\u00f8lsomhed.<\/p>\r\n<p data-start=\"4924\" data-end=\"5057\"><strong data-start=\"4924\" data-end=\"4976\">1. Match systemsp\u00e6nding og jordingsarrangement<\/strong><br data-start=\"4976\" data-end=\"4979\" \/>Forskellige systemer - TT, TN-S, TN-C, IT - kr\u00e6ver forskellige SPD-konfigurationer:<\/p>\r\n\r\n<ul data-start=\"5058\" data-end=\"5212\">\r\n \t<li data-start=\"5058\" data-end=\"5104\">\r\n<p data-start=\"5060\" data-end=\"5104\"><strong data-start=\"5060\" data-end=\"5066\">4P<\/strong> (all-polet beskyttelse) til TN-systemer.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5105\" data-end=\"5212\">\r\n<p data-start=\"5107\" data-end=\"5212\"><strong data-start=\"5107\" data-end=\"5114\">3+1<\/strong> konfiguration (L-N-beskyttelse plus N-PE-modul) til TT-systemer til at h\u00e5ndtere N-PE-oversp\u00e6ndingsh\u00e6ndelser.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"5214\" data-end=\"5404\"><strong data-start=\"5214\" data-end=\"5272\">2. Bestem Uc (maksimal kontinuerlig driftssp\u00e6nding)<\/strong><br data-start=\"5272\" data-end=\"5275\" \/>Uc b\u00f8r v\u00e6re lidt over den nominelle systemsp\u00e6nding for at forhindre un\u00f8dvendig udl\u00f8sning, men lav nok til effektiv beskyttelse.<\/p>\r\n<p data-start=\"5406\" data-end=\"5449\"><strong data-start=\"5406\" data-end=\"5447\">3. Tjek afladningsstr\u00f8mkapaciteten<\/strong><\/p>\r\n\r\n<ul data-start=\"5450\" data-end=\"5570\">\r\n \t<li data-start=\"5450\" data-end=\"5496\">\r\n<p data-start=\"5452\" data-end=\"5496\"><strong data-start=\"5452\" data-end=\"5487\">Nominel afladningsstr\u00f8m (In):<\/strong> 5-20 kA.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5497\" data-end=\"5570\">\r\n<p data-start=\"5499\" data-end=\"5570\"><strong data-start=\"5499\" data-end=\"5536\">Maksimal afladningsstr\u00f8m (Imax):<\/strong> 20\u201380 kA afh\u00e6ngig af risikoniveau.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"5572\" data-end=\"5721\"><strong data-start=\"5572\" data-end=\"5608\">4. Sp\u00e6ndingsbeskyttelsesniveau (Op)<\/strong><br data-start=\"5608\" data-end=\"5611\" \/>Lavere op betyder bedre beskyttelse \u2014 sigt efter \u2264 2,5 kV for almindeligt udstyr, \u2264 1,5 kV for f\u00f8lsom elektronik.<\/p>\r\n<p data-start=\"5723\" data-end=\"5862\"><strong data-start=\"5723\" data-end=\"5767\">5. Midlertidig oversp\u00e6nding (TOV) modst\u00e5<\/strong><br data-start=\"5767\" data-end=\"5770\" \/>S\u00f8rg for, at SPD'en kan overleve midlertidige oversp\u00e6ndingsforhold fra fejl eller koblingsh\u00e6ndelser.<\/p>\r\n<p data-start=\"5864\" data-end=\"5892\"><strong data-start=\"5864\" data-end=\"5890\">6. Yderligere funktioner<\/strong><\/p>\r\n\r\n<ul data-start=\"5893\" data-end=\"6019\">\r\n \t<li data-start=\"5893\" data-end=\"5935\">\r\n<p data-start=\"5895\" data-end=\"5935\">Pluggbare moduler til hurtig vedligeholdelse.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5936\" data-end=\"5975\">\r\n<p data-start=\"5938\" data-end=\"5975\">Fjernalarmkontakter til overv\u00e5gning.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5976\" data-end=\"6019\">\r\n<p data-start=\"5978\" data-end=\"6019\">Termisk afbrydelse og visuelle indikatorer.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"6026\" data-end=\"6076\">S\u00e5dan installeres en type 2 oversp\u00e6ndingsbeskyttelsesenhed<\/h2>\r\n<a href=\"https:\/\/www.britecelectric.com\/da\/attachment\/type-2-spd-install\/\" rel=\"attachment wp-att-2158\"><img class=\"alignnone size-full wp-image-2158\" src=\"https:\/\/www.britecelectric.com\/wp-content\/uploads\/2025\/08\/Type-2-SPD-install.jpg\" alt=\"\" width=\"732\" height=\"615\" \/><\/a>\r\n<p data-start=\"6078\" data-end=\"6144\"><strong data-start=\"6078\" data-end=\"6144\">Best practices for installation fra feltingeni\u00f8rerfaring:<\/strong><\/p>\r\n\r\n<ol data-start=\"6145\" data-end=\"7145\">\r\n \t<li data-start=\"6145\" data-end=\"6266\">\r\n<p data-start=\"6148\" data-end=\"6266\"><strong data-start=\"6148\" data-end=\"6160\">Beliggenhed<\/strong> \u2014 Monter s\u00e5 t\u00e6t som muligt p\u00e5 hovedfordelingstavlens samleskinner eller det udstyr, du \u00f8nsker at beskytte.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6267\" data-end=\"6362\">\r\n<p data-start=\"6270\" data-end=\"6362\"><strong data-start=\"6270\" data-end=\"6293\">Parallel forbindelse<\/strong> \u2014 Type 2 SPD'er er normalt forbundet parallelt med str\u00f8mforsyningen.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6363\" data-end=\"6506\">\r\n<p data-start=\"6366\" data-end=\"6506\"><strong data-start=\"6366\" data-end=\"6381\">Blyl\u00e6ngde<\/strong> \u2014 Hold den kombinerede l\u00e6ngde af fase-, nul- og jordledere under 0,5 m for at undg\u00e5 at h\u00e6ve beskyttelsessp\u00e6ndingen.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6507\" data-end=\"6619\">\r\n<p data-start=\"6510\" data-end=\"6619\"><strong data-start=\"6510\" data-end=\"6537\">Ledertv\u00e6rsnit<\/strong> \u2014 Mindst 6 mm\u00b2 kobber for Type 2; st\u00f8rre st\u00f8rrelser til enheder med h\u00f8jere kapacitet.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6620\" data-end=\"6716\">\r\n<p data-start=\"6623\" data-end=\"6716\"><strong data-start=\"6623\" data-end=\"6635\">Jording<\/strong> \u2014 Tilslut direkte til hovedpotentialudligningsstangen med den korteste vej.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6717\" data-end=\"6840\">\r\n<p data-start=\"6720\" data-end=\"6840\"><strong data-start=\"6720\" data-end=\"6746\">Overstr\u00f8msbeskyttelse<\/strong> \u2014 Use fuses or circuit breakers sized according to the SPD's maximum short-circuit withstand.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6841\" data-end=\"7028\">\r\n<p data-start=\"6844\" data-end=\"7028\"><strong data-start=\"6844\" data-end=\"6880\">Koordinering i kaskadesystemer<\/strong> \u2014 Hvis den installeres nedstr\u00f8ms for en Type 1 SPD, skal du holde en adskillelsesafstand (&gt;10 m) eller installere en afkoblingsspole for at sikre korrekt energideling.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7029\" data-end=\"7145\">\r\n<p data-start=\"7032\" data-end=\"7145\"><strong data-start=\"7032\" data-end=\"7058\">Systemspecifik ledningsf\u00f8ring<\/strong> \u2014 Til TT-systemer skal der inkluderes et N-PE-beskyttelsesmodul til at h\u00e5ndtere oversp\u00e6ndinger fra jordoverfladen.<\/p>\r\n<\/li>\r\n<\/ol>\r\n<p data-start=\"7147\" data-end=\"7255\">At f\u00f8lge disse retningslinjer sikrer, at SPD'en fungerer efter specifikationerne og overholder elektriske standarder.<\/p>\r\n\r\n<h2 data-start=\"7262\" data-end=\"7275\">Konklusion<\/h2>\r\n<p data-start=\"7277\" data-end=\"7508\">A <em><a href=\"https:\/\/www.britecelectric.com\/da\/product-category\/ac-power-surge-protection\/type-2-surge-protective-device\/\" target=\"_blank\" rel=\"noopener\"><strong data-start=\"7279\" data-end=\"7313\">Type 2 oversp\u00e6ndingsbeskyttelsesenhed<\/strong><\/a><\/em> er et vigtigt element i lagdelt elektrisk beskyttelse. Det sikrer mod resterende oversp\u00e6ndinger fra lynnedslag og interne koblingsh\u00e6ndelser, hvilket sikrer udstyrets levetid og driftsstabilitet.<\/p>\r\n<p data-start=\"7510\" data-end=\"7767\">Ved at forst\u00e5 dets arbejdsprincip, installationsregler og udv\u00e6lgelsesparametre kan ingeni\u00f8rer og indk\u00f8bsledere specificere enheder, der opfylder systemkravene, overholder IEC\/EN 61643-11 og leverer p\u00e5lidelig beskyttelse i mange \u00e5r fremover.<\/p>\r\n<p data-start=\"7769\" data-end=\"7951\">Korrekt installeret er en Type 2 SPD ikke bare en komponent - det er en forsikring for dit elektriske system. F\u00e5 mere at vide om <strong><em><a class=\"\" href=\"https:\/\/www.britecelectric.com\/da\/blog\/surge-protection-for-solar-photovoltaic-systems\/\" target=\"_blank\" rel=\"noopener\" data-start=\"1609\" data-end=\"1719\">solar SPD applikationer<\/a><\/em><\/strong> og hvordan man v\u00e6lger den rigtige.<\/p>","protected":false},"featured_media":2160,"parent":0,"menu_order":127,"template":"","meta":{"_acf_changed":false},"blog_category":[9],"class_list":["post-2154","blog","type-blog","status-publish","has-post-thumbnail","hentry","blog_category-industry-news"],"acf":{"des":"A Type 2 Surge Protection Device protects electrical systems from residual surges and switching surges. It is installed at the main distribution board. It works with Type 1 and Type 3 SPDs to form layered protection. This blog explains how it works, where to use it, how to choose it, and how to install it.","txt":"<h2 data-start=\"226\" data-end=\"241\">Introduction<\/h2>\r\n<p data-start=\"243\" data-end=\"597\">A <a href=\"https:\/\/www.britecelectric.com\/product-category\/ac-power-surge-protection\/type-2-surge-protective-device\/\"><strong data-start=\"245\" data-end=\"279\">Type 2 Surge Protection Device<\/strong><\/a> (Type 2 SPD) is the backbone of surge protection inside modern electrical systems. Installed at the main distribution board or control cabinet, it acts as the second shield in a layered defense strategy \u2014 catching residual surges left by upstream Type 1 SPDs and suppressing transients generated inside the network.<\/p>\r\n<p data-start=\"599\" data-end=\"986\">These devices protect against 8\/20 \u03bcs impulse currents that occur from lightning-induced surges, switching events, or utility disturbances.<\/p>\r\nTo ensure reliable, long-term protection, engineers and technical buyers need to understand several key aspects of a Type 2 SPD:\r\n<ul>\r\n \t<li><b>Definition:<\/b> What is it?<\/li>\r\n \t<li><b>How it works:<\/b> Its operating principles.<\/li>\r\n \t<li><b>Standards:<\/b> Which regulations does it meet?<\/li>\r\n \t<li><b>Installation and Selection:<\/b> The rules for choosing and installing it correctly.<\/li>\r\n<\/ul>\r\n<h2 data-start=\"993\" data-end=\"1042\">Definition of a Type 2 Surge Protection Device<\/h2>\r\n<p data-start=\"1044\" data-end=\"1268\">According to the <a href=\"https:\/\/webstore.iec.ch\/en\/publication\/65314\" target=\"_blank\" rel=\"noopener\"><em><strong>IEC\/EN 61643-11 standard<\/strong><\/em><\/a>, a **Type 2 SPD** is a Class II device. It is designed for locations that do not have direct lightning strikes. However, these locations still face a risk of strong transient overvoltages..<\/p>\r\n<p data-start=\"1270\" data-end=\"1290\">Key characteristics:<\/p>\r\n\r\n<ul data-start=\"1291\" data-end=\"1618\">\r\n \t<li data-start=\"1291\" data-end=\"1335\">\r\n<p data-start=\"1293\" data-end=\"1335\">Tested with 8\/20 \u03bcs current waveforms.<\/p>\r\n<\/li>\r\n \t<li data-start=\"1336\" data-end=\"1466\">\r\n<p data-start=\"1338\" data-end=\"1466\">Typical nominal discharge current (In) is between 5\u201320 kA, with maximum discharge current (Imax) up to 40\u201380 kA.<\/p>\r\n<\/li>\r\n \t<li data-start=\"1467\" data-end=\"1530\">\r\n<p data-start=\"1469\" data-end=\"1530\">Mounted on the load side of the electrical service panel.<\/p>\r\n<\/li>\r\n \t<li data-start=\"1531\" data-end=\"1618\">\r\n<p data-start=\"1533\" data-end=\"1618\">Protects against both external residual surges and internal switching surges.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"1620\" data-end=\"1802\">In practical application, a Type 2 SPD sits after a Type 1 device and before any downstream Type 3 point-of-use protection, forming part of a multi-stage surge protection system.<\/p>\r\n<p data-start=\"1620\" data-end=\"1802\"><a href=\"https:\/\/www.britecelectric.com\/product-category\/ac-power-surge-protection\/type-2-surge-protective-device\/\" target=\"_blank\" rel=\"noopener\"><img class=\"alignnone  wp-image-2160\" src=\"https:\/\/www.britecelectric.com\/wp-content\/uploads\/2025\/08\/BR-20-4P-1Type-2-Surge-Protection-Device.jpg-1024x1024.webp\" alt=\"\" width=\"900\" height=\"900\" \/><\/a><\/p>\r\n\r\n<h2 data-start=\"1809\" data-end=\"1859\">How does a <a href=\"https:\/\/www.britecelectric.com\/product-category\/ac-power-surge-protection\/type-2-surge-protective-device\/\" target=\"_blank\" rel=\"noopener\">Type 2 Surge Protection Device<\/a> work?<\/h2>\r\n<p data-start=\"1861\" data-end=\"2143\">A Type 2 SPD operates on the voltage clamping principle. Under normal voltage, it remains passive. When a transient surge exceeds its maximum continuous operating voltage (Uc), its internal components switch rapidly to a conductive state, shunting excess energy to ground.<\/p>\r\n<p data-start=\"2145\" data-end=\"2176\"><strong data-start=\"2145\" data-end=\"2176\">Typical components include:<\/strong><\/p>\r\n\r\n<ul data-start=\"2177\" data-end=\"2557\">\r\n \t<li data-start=\"2177\" data-end=\"2285\">\r\n<p data-start=\"2179\" data-end=\"2285\"><strong data-start=\"2179\" data-end=\"2210\">MOV (Metal Oxide Varistor):<\/strong> The primary clamping element, absorbing surge energy and reducing voltage.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2286\" data-end=\"2385\">\r\n<p data-start=\"2288\" data-end=\"2385\"><strong data-start=\"2288\" data-end=\"2320\">Hybrid circuits (MOV + GDT):<\/strong> Combine high surge capacity with improved long-term reliability.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2386\" data-end=\"2470\">\r\n<p data-start=\"2388\" data-end=\"2470\"><strong data-start=\"2388\" data-end=\"2418\">Thermal disconnect system:<\/strong> Isolates the SPD at end-of-life to maintain safety.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2471\" data-end=\"2557\">\r\n<p data-start=\"2473\" data-end=\"2557\"><strong data-start=\"2473\" data-end=\"2494\">Status indicator:<\/strong> Visual window or contact output to show operational condition.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"2559\" data-end=\"2582\"><strong data-start=\"2559\" data-end=\"2582\">Operation sequence:<\/strong><\/p>\r\n\r\n<ol data-start=\"2583\" data-end=\"2882\">\r\n \t<li data-start=\"2583\" data-end=\"2645\">\r\n<p data-start=\"2586\" data-end=\"2645\"><strong data-start=\"2586\" data-end=\"2602\">Normal mode:<\/strong> High resistance, no impact on the circuit.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2646\" data-end=\"2699\">\r\n<p data-start=\"2649\" data-end=\"2699\"><strong data-start=\"2649\" data-end=\"2665\">Surge event:<\/strong> Voltage rises above the Uc threshold.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2700\" data-end=\"2819\">\r\n<p data-start=\"2703\" data-end=\"2819\"><strong data-start=\"2703\" data-end=\"2716\">Clamping:<\/strong> SPD diverts surge current to ground, lowering the voltage to a safe Up (voltage protection level).<\/p>\r\n<\/li>\r\n \t<li data-start=\"2820\" data-end=\"2882\">\r\n<p data-start=\"2823\" data-end=\"2882\"><strong data-start=\"2823\" data-end=\"2836\">Recovery:<\/strong> SPD returns to high-resistance standby state.<\/p>\r\n<\/li>\r\n<\/ol>\r\n<h2 data-start=\"2889\" data-end=\"2940\">The function of a Type 2 Surge Protection Device<\/h2>\r\n<p data-start=\"2942\" data-end=\"3106\">The primary role of a surge protection device Type 2 is to limit transient overvoltages to a level that downstream equipment can withstand without damage.<\/p>\r\n<p data-start=\"3108\" data-end=\"3122\">Key functions:<\/p>\r\n\r\n<ul data-start=\"3123\" data-end=\"3659\">\r\n \t<li data-start=\"3123\" data-end=\"3228\">\r\n<p data-start=\"3125\" data-end=\"3228\"><strong data-start=\"3125\" data-end=\"3154\">Residual surge limitation<\/strong> \u2014 reduces voltage after a Type 1 SPD has absorbed the bulk of the energy.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3229\" data-end=\"3356\">\r\n<p data-start=\"3231\" data-end=\"3356\"><strong data-start=\"3231\" data-end=\"3262\">Switching surge suppression<\/strong> \u2014 mitigates transients from motor starts, pump switching, or other inductive load operations.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3357\" data-end=\"3471\">\r\n<p data-start=\"3359\" data-end=\"3471\"><strong data-start=\"3359\" data-end=\"3383\">Equipment protection<\/strong> \u2014 prevents damage to sensitive electronics, PLCs, automation systems, and control gear.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3472\" data-end=\"3544\">\r\n<p data-start=\"3474\" data-end=\"3544\"><strong data-start=\"3474\" data-end=\"3496\">System reliability<\/strong> \u2014 reduces downtime from surge-related failures.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3545\" data-end=\"3659\">\r\n<p data-start=\"3547\" data-end=\"3659\"><strong data-start=\"3547\" data-end=\"3568\">Part of a cascade<\/strong> \u2014 sits between the service entrance protection (Type 1) and point-of-use devices (Type 3).<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"3666\" data-end=\"3716\">Applications of Type 2 Surge Protection Devices<\/h2>\r\n<a href=\"https:\/\/www.britecelectric.com\/attachment\/spd-install\/\" rel=\"attachment wp-att-2159\"><img class=\"alignnone size-full wp-image-2159\" src=\"https:\/\/www.britecelectric.com\/wp-content\/uploads\/2025\/08\/SPD-install.jpg\" alt=\"\" width=\"745\" height=\"609\" \/><\/a>\r\n<p data-start=\"3718\" data-end=\"3747\">Type 2 SPDs are installed in:<\/p>\r\n\r\n<ul data-start=\"3748\" data-end=\"4151\">\r\n \t<li data-start=\"3748\" data-end=\"3810\">\r\n<p data-start=\"3750\" data-end=\"3810\">Industrial facilities with lightning protection systems.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3811\" data-end=\"3891\">\r\n<p data-start=\"3813\" data-end=\"3891\">Commercial buildings to protect HVAC, elevators, lighting, and IT systems.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3892\" data-end=\"3949\">\r\n<p data-start=\"3894\" data-end=\"3949\">Machine control cabinets for industrial automation.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3950\" data-end=\"4034\">\r\n<p data-start=\"3952\" data-end=\"4034\">Renewable energy systems\u2014such as solar PV inverters and wind turbine controls\u2014require robust <a href=\"https:\/\/www.britecelectric.com\/product_category\/pv-surge-protection-type-2\/\" target=\"_blank\" rel=\"noopener\">surge protection<\/a> (see our <strong><em><a class=\"\" href=\"https:\/\/www.britecelectric.com\/blog\/solar-surge-protection-devices-selection-guide\/\" target=\"_blank\" rel=\"noopener\" data-start=\"201\" data-end=\"334\">Solar Surge Protection Devices Selection Guide<\/a><\/em><\/strong> and <strong><em><a class=\"\" href=\"https:\/\/www.britecelectric.com\/blog\/surge-protection-for-solar-photovoltaic-systems\/\" target=\"_blank\" rel=\"noopener\" data-start=\"339\" data-end=\"474\">Surge Protection for Solar Photovoltaic Systems<\/a><\/em><\/strong>).<\/p>\r\n<\/li>\r\n \t<li data-start=\"4035\" data-end=\"4093\">\r\n<p data-start=\"4037\" data-end=\"4093\">Hospitals and data centers where uptime is critical.<\/p>\r\n<\/li>\r\n \t<li data-start=\"4094\" data-end=\"4151\">\r\n<p data-start=\"4096\" data-end=\"4151\">Residential main panels for whole-house protection.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"262\" data-end=\"316\">Type 1, Type 2, and Type 3 Surge Protection Devices<\/h2>\r\n<p data-start=\"318\" data-end=\"648\">Surge protection devices have three main types. Each type has a different job in the electrical system. You can read more in our detailed guide here: <em><strong><a class=\"\" href=\"https:\/\/www.britecelectric.com\/blog\/difference-between-type-1-type-2-and-type-3-surge-protective-devices\/\" target=\"_blank\" rel=\"noopener\" data-start=\"468\" data-end=\"647\">Difference Between Type 1, Type 2, and Type 3 Surge Protective Devices<\/a>.<\/strong><\/em><\/p>\r\n\r\n<table style=\"width: 60.5183%;\">\r\n<tbody>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\"><strong><b>Feature<\/b><\/strong><\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\"><strong><b>Type 1 SPD<\/b><\/strong><\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\"><strong><b>Type 2 SPD<\/b><\/strong><\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\"><strong><b>Type 3 SPD<\/b><\/strong><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Location<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">Installed at the service entrance.<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">Installed at the main distribution board.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">Installed close to sensitive loads.<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Test waveform<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">Tested with 10\/350 \u03bcs lightning impulse.<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">Tested with 8\/20 \u03bcs surge current.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">Tested with 1.2\/50 \u03bcs voltage + 8\/20 \u03bcs current.<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Purpose<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">Discharges direct lightning current.<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">Limits residual surges and switching surges.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">Gives final protection for electronics.<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Typical Up<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">\u2264 4 kV.<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">\u2264 2.5 kV.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">\u2264 1.5 kV.<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Examples<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">Buildings with a lightning protection system (LPS).<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">Control panels and sub-distribution boards.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">IT equipment and home electronics.<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<p data-start=\"1409\" data-end=\"1423\"><strong data-start=\"1409\" data-end=\"1421\">Summary:<\/strong><\/p>\r\n\r\n<ul data-start=\"1424\" data-end=\"1706\">\r\n \t<li data-start=\"1424\" data-end=\"1494\">\r\n<p data-start=\"1426\" data-end=\"1494\"><strong data-start=\"1426\" data-end=\"1440\">Type 1 SPD<\/strong> stops most of the high-energy surge from lightning.<\/p>\r\n<\/li>\r\n \t<li data-start=\"1495\" data-end=\"1610\">\r\n<p data-start=\"1497\" data-end=\"1610\"><strong data-start=\"1497\" data-end=\"1511\">Type 2 SPD<\/strong> is the middle line of defense. It reduces remaining surge voltage and controls switching surges.<\/p>\r\n<\/li>\r\n \t<li data-start=\"1611\" data-end=\"1706\">\r\n<p data-start=\"1613\" data-end=\"1706\"><strong data-start=\"1613\" data-end=\"1627\">Type 3 SPD<\/strong> is the last step. It protects sensitive electronics from small, fast surges.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"4715\" data-end=\"4766\">How to select the right surge protection device?<\/h2>\r\n<p data-start=\"4768\" data-end=\"4922\">When choosing the best Type 2 surge protection device, selection should be based on system compatibility, surge risk level, and equipment sensitivity.<\/p>\r\n<p data-start=\"4924\" data-end=\"5057\"><strong data-start=\"4924\" data-end=\"4976\">1. Match system voltage and earthing arrangement<\/strong><br data-start=\"4976\" data-end=\"4979\" \/>Different systems \u2014 TT, TN-S, TN-C, IT \u2014 require different SPD configurations:<\/p>\r\n\r\n<ul data-start=\"5058\" data-end=\"5212\">\r\n \t<li data-start=\"5058\" data-end=\"5104\">\r\n<p data-start=\"5060\" data-end=\"5104\"><strong data-start=\"5060\" data-end=\"5066\">4P<\/strong> (all-pole protection) for TN systems.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5105\" data-end=\"5212\">\r\n<p data-start=\"5107\" data-end=\"5212\"><strong data-start=\"5107\" data-end=\"5114\">3+1<\/strong> configuration (L-N protection plus N-PE module) for TT systems to handle N-PE overvoltage events.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"5214\" data-end=\"5404\"><strong data-start=\"5214\" data-end=\"5272\">2. Determine Uc (Maximum Continuous Operating Voltage)<\/strong><br data-start=\"5272\" data-end=\"5275\" \/>Uc should be slightly above the nominal system voltage to prevent unnecessary triggering but low enough for effective protection.<\/p>\r\n<p data-start=\"5406\" data-end=\"5449\"><strong data-start=\"5406\" data-end=\"5447\">3. Check discharge current capability<\/strong><\/p>\r\n\r\n<ul data-start=\"5450\" data-end=\"5570\">\r\n \t<li data-start=\"5450\" data-end=\"5496\">\r\n<p data-start=\"5452\" data-end=\"5496\"><strong data-start=\"5452\" data-end=\"5487\">Nominal discharge current (In):<\/strong> 5\u201320 kA.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5497\" data-end=\"5570\">\r\n<p data-start=\"5499\" data-end=\"5570\"><strong data-start=\"5499\" data-end=\"5536\">Maximum discharge current (Imax):<\/strong> 20\u201380 kA depending on risk level.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"5572\" data-end=\"5721\"><strong data-start=\"5572\" data-end=\"5608\">4. Voltage protection level (Up)<\/strong><br data-start=\"5608\" data-end=\"5611\" \/>Lower Up means better protection \u2014 aim for \u2264 2.5 kV for general equipment, \u2264 1.5 kV for sensitive electronics.<\/p>\r\n<p data-start=\"5723\" data-end=\"5862\"><strong data-start=\"5723\" data-end=\"5767\">5. Temporary overvoltage (TOV) withstand<\/strong><br data-start=\"5767\" data-end=\"5770\" \/>Ensure the SPD can survive temporary overvoltage conditions from faults or switching events.<\/p>\r\n<p data-start=\"5864\" data-end=\"5892\"><strong data-start=\"5864\" data-end=\"5890\">6. Additional features<\/strong><\/p>\r\n\r\n<ul data-start=\"5893\" data-end=\"6019\">\r\n \t<li data-start=\"5893\" data-end=\"5935\">\r\n<p data-start=\"5895\" data-end=\"5935\">Pluggable modules for quick maintenance.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5936\" data-end=\"5975\">\r\n<p data-start=\"5938\" data-end=\"5975\">Remote alarm contacts for monitoring.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5976\" data-end=\"6019\">\r\n<p data-start=\"5978\" data-end=\"6019\">Thermal disconnect and visual indicators.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"6026\" data-end=\"6076\">How to install a Type 2 surge protection device<\/h2>\r\n<a href=\"https:\/\/www.britecelectric.com\/attachment\/type-2-spd-install\/\" rel=\"attachment wp-att-2158\"><img class=\"alignnone size-full wp-image-2158\" src=\"https:\/\/www.britecelectric.com\/wp-content\/uploads\/2025\/08\/Type-2-SPD-install.jpg\" alt=\"\" width=\"732\" height=\"615\" \/><\/a>\r\n<p data-start=\"6078\" data-end=\"6144\"><strong data-start=\"6078\" data-end=\"6144\">Installation best practices from field engineering experience:<\/strong><\/p>\r\n\r\n<ol data-start=\"6145\" data-end=\"7145\">\r\n \t<li data-start=\"6145\" data-end=\"6266\">\r\n<p data-start=\"6148\" data-end=\"6266\"><strong data-start=\"6148\" data-end=\"6160\">Location<\/strong> \u2014 Mount as close as possible to the main distribution board busbars or the equipment you want to protect.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6267\" data-end=\"6362\">\r\n<p data-start=\"6270\" data-end=\"6362\"><strong data-start=\"6270\" data-end=\"6293\">Parallel connection<\/strong> \u2014 Type 2 SPDs are usually connected in parallel to the power supply.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6363\" data-end=\"6506\">\r\n<p data-start=\"6366\" data-end=\"6506\"><strong data-start=\"6366\" data-end=\"6381\">Lead length<\/strong> \u2014 Keep the combined length of phase, neutral, and ground conductors under 0.5 m to avoid raising the protection voltage.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6507\" data-end=\"6619\">\r\n<p data-start=\"6510\" data-end=\"6619\"><strong data-start=\"6510\" data-end=\"6537\">Conductor cross-section<\/strong> \u2014 At least 6 mm\u00b2 copper for Type 2; larger sizes for higher-capacity devices.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6620\" data-end=\"6716\">\r\n<p data-start=\"6623\" data-end=\"6716\"><strong data-start=\"6623\" data-end=\"6635\">Earthing<\/strong> \u2014 Connect directly to the main equipotential bonding bar with the shortest path.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6717\" data-end=\"6840\">\r\n<p data-start=\"6720\" data-end=\"6840\"><strong data-start=\"6720\" data-end=\"6746\">Overcurrent protection<\/strong> \u2014 Use fuses or circuit breakers sized according to the SPD's maximum short-circuit withstand.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6841\" data-end=\"7028\">\r\n<p data-start=\"6844\" data-end=\"7028\"><strong data-start=\"6844\" data-end=\"6880\">Coordination in cascaded systems<\/strong> \u2014 If installed downstream of a Type 1 SPD, maintain a separation distance (&gt;10 m) or install a decoupling inductor to ensure proper energy sharing.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7029\" data-end=\"7145\">\r\n<p data-start=\"7032\" data-end=\"7145\"><strong data-start=\"7032\" data-end=\"7058\">System-specific wiring<\/strong> \u2014 For TT systems, include an N-PE protection module to handle neutral-to-earth surges.<\/p>\r\n<\/li>\r\n<\/ol>\r\n<p data-start=\"7147\" data-end=\"7255\">Following these guidelines ensures the SPD performs to specification and complies with electrical standards.<\/p>\r\n\r\n<h2 data-start=\"7262\" data-end=\"7275\">Conclusion<\/h2>\r\n<p data-start=\"7277\" data-end=\"7508\">A <em><a href=\"https:\/\/www.britecelectric.com\/product-category\/ac-power-surge-protection\/type-2-surge-protective-device\/\" target=\"_blank\" rel=\"noopener\"><strong data-start=\"7279\" data-end=\"7313\">Type 2 Surge Protection Device<\/strong><\/a><\/em> is a vital element in layered electrical protection. It safeguards against residual surges from lightning and internal switching events, ensuring equipment longevity and operational stability.<\/p>\r\n<p data-start=\"7510\" data-end=\"7767\">By understanding its working principle, installation rules, and selection parameters, engineers and procurement managers can specify devices that meet system requirements, comply with IEC\/EN 61643-11, and deliver reliable protection for years to come.<\/p>\r\n<p data-start=\"7769\" data-end=\"7951\">Correctly installed, a Type 2 SPD is not just a component \u2014 it\u2019s an insurance policy for your electrical system. Learn more about <strong><em><a class=\"\" href=\"https:\/\/www.britecelectric.com\/blog\/surge-protection-for-solar-photovoltaic-systems\/\" target=\"_blank\" rel=\"noopener\" data-start=\"1609\" data-end=\"1719\">solar SPD applications<\/a><\/em><\/strong> and how to choose the right one.<\/p>"},"_links":{"self":[{"href":"https:\/\/www.britecelectric.com\/da\/wp-json\/wp\/v2\/blog\/2154","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.britecelectric.com\/da\/wp-json\/wp\/v2\/blog"}],"about":[{"href":"https:\/\/www.britecelectric.com\/da\/wp-json\/wp\/v2\/types\/blog"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.britecelectric.com\/da\/wp-json\/wp\/v2\/media\/2160"}],"wp:attachment":[{"href":"https:\/\/www.britecelectric.com\/da\/wp-json\/wp\/v2\/media?parent=2154"}],"wp:term":[{"taxonomy":"blog_category","embeddable":true,"href":"https:\/\/www.britecelectric.com\/da\/wp-json\/wp\/v2\/blog_category?post=2154"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}