{"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\/fi\/blog\/what-is-a-type-2-surge-protection-device\/","title":{"rendered":"Mik\u00e4 on tyypin 2 ylij\u00e4nnitesuojalaite?"},"content":{"rendered":"<h2 data-start=\"226\" data-end=\"241\">Johdanto<\/h2>\r\n<p data-start=\"243\" data-end=\"597\">A <a href=\"https:\/\/www.britecelectric.com\/fi\/product-category\/ac-power-surge-protection\/type-2-surge-protective-device\/\"><strong data-start=\"245\" data-end=\"279\">Tyypin 2 ylij\u00e4nnitesuojalaite<\/strong><\/a> (Type 2 SPD) on ylij\u00e4nnitesuojan selk\u00e4ranka nykyaikaisissa s\u00e4hk\u00f6j\u00e4rjestelmiss\u00e4. P\u00e4\u00e4jakokeskukseen tai ohjauskaappiin asennettuna se toimii toisena suojana kerroksellisessa puolustusstrategiassa \u2013 sieppaa yl\u00e4virran tyypin 1 SPD:n j\u00e4tt\u00e4m\u00e4t j\u00e4\u00e4nn\u00f6spiikit ja vaimentaa verkon sis\u00e4ll\u00e4 syntyvi\u00e4 transientteja.<\/p>\r\n<p data-start=\"599\" data-end=\"986\">N\u00e4m\u00e4 laitteet suojaavat 8\/20 \u03bcs:n impulssivirroilta, jotka syntyv\u00e4t salaman aiheuttamista j\u00e4nnitteist\u00e4, kytkent\u00e4tapahtumista tai k\u00e4ytt\u00f6h\u00e4iri\u00f6ist\u00e4.<\/p>\r\nLuotettavan ja pitk\u00e4aikaisen suojan varmistamiseksi insin\u00f6\u00f6rien ja teknisten ostajien on ymm\u00e4rrett\u00e4v\u00e4 useita tyypin 2 SPD:n t\u00e4rkeimpi\u00e4 n\u00e4k\u00f6kohtia:\r\n<ul>\r\n \t<li><b>M\u00e4\u00e4ritelm\u00e4:<\/b> Mik\u00e4 se on?<\/li>\r\n \t<li><b>Miten se toimii:<\/b> Sen toimintaperiaatteet.<\/li>\r\n \t<li><b>Standardit:<\/b> Mit\u00e4 s\u00e4\u00e4nt\u00f6j\u00e4 se t\u00e4ytt\u00e4\u00e4?<\/li>\r\n \t<li><b>Asennus ja valinta:<\/b> Oikean valinnan ja asennuksen s\u00e4\u00e4nn\u00f6t.<\/li>\r\n<\/ul>\r\n<h2 data-start=\"993\" data-end=\"1042\">Tyypin 2 ylij\u00e4nnitesuojalaitteen m\u00e4\u00e4ritelm\u00e4<\/h2>\r\n<p data-start=\"1044\" data-end=\"1268\">mukaan <a href=\"https:\/\/webstore.iec.ch\/en\/publication\/65314\" target=\"_blank\" rel=\"noopener\"><em><strong>IEC\/EN 61643-11 -standardi<\/strong><\/em><\/a>, **tyypin 2 SPD** on luokan II laite. Se on suunniteltu paikkoihin, joissa ei ole suoria salamaniskuja. N\u00e4iss\u00e4 paikoissa on kuitenkin edelleen vaarana voimakkaat ohimenev\u00e4t ylij\u00e4nnitteet.<\/p>\r\n<p data-start=\"1270\" data-end=\"1290\">T\u00e4rkeimm\u00e4t ominaisuudet:<\/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\">Testattu 8\/20 \u03bcs virran aaltomuodoilla.<\/p>\r\n<\/li>\r\n \t<li data-start=\"1336\" data-end=\"1466\">\r\n<p data-start=\"1338\" data-end=\"1466\">Tyypillinen nimellinen purkausvirta (In) on v\u00e4lill\u00e4 5\u201320 kA ja maksimipurkausvirta (Imax) on 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\">Asennettu s\u00e4hk\u00f6isen huoltopaneelin kuorman puolelle.<\/p>\r\n<\/li>\r\n \t<li data-start=\"1531\" data-end=\"1618\">\r\n<p data-start=\"1533\" data-end=\"1618\">Suojaa sek\u00e4 ulkoisilta j\u00e4\u00e4nn\u00f6spiikkeilt\u00e4 ett\u00e4 sis\u00e4isilt\u00e4 kytkent\u00e4piikeilt\u00e4.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"1620\" data-end=\"1802\">K\u00e4yt\u00e4nn\u00f6ss\u00e4 tyypin 2 SPD sijaitsee tyypin 1 laitteen j\u00e4lkeen ja ennen tyypin 3 k\u00e4ytt\u00f6pistesuojausta, mik\u00e4 on osa monivaiheista ylij\u00e4nnitesuojaj\u00e4rjestelm\u00e4\u00e4.<\/p>\r\n<p data-start=\"1620\" data-end=\"1802\"><a href=\"https:\/\/www.britecelectric.com\/fi\/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\">Miten a <a href=\"https:\/\/www.britecelectric.com\/fi\/product-category\/ac-power-surge-protection\/type-2-surge-protective-device\/\" target=\"_blank\" rel=\"noopener\">Tyypin 2 ylij\u00e4nnitesuojalaite<\/a> ty\u00f6t\u00e4?<\/h2>\r\n<p data-start=\"1861\" data-end=\"2143\">Tyypin 2 SPD toimii j\u00e4nnitteen kiinnitysperiaatteella. Normaalilla j\u00e4nnitteell\u00e4 se pysyy passiivisena. Kun ohimenev\u00e4 ylij\u00e4nnite ylitt\u00e4\u00e4 suurimman jatkuvan k\u00e4ytt\u00f6j\u00e4nnitteen (Uc), sen sis\u00e4iset komponentit siirtyv\u00e4t nopeasti johtavaan tilaan, jolloin ylim\u00e4\u00e4r\u00e4inen energia siirtyy maahan.<\/p>\r\n<p data-start=\"2145\" data-end=\"2176\"><strong data-start=\"2145\" data-end=\"2176\">Tyypillisi\u00e4 komponentteja ovat:<\/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> Ensisijainen kiinnityselementti, joka absorboi ylij\u00e4nniteenergiaa ja v\u00e4hent\u00e4\u00e4 j\u00e4nnitett\u00e4.<\/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\">Hybridipiirit (MOV + GDT):<\/strong> Yhdist\u00e4 korkea ylij\u00e4nnitekapasiteetti parantuneeseen pitk\u00e4n aikav\u00e4lin luotettavuuteen.<\/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\">L\u00e4mp\u00f6erotusj\u00e4rjestelm\u00e4:<\/strong> Erist\u00e4\u00e4 SPD:n k\u00e4ytt\u00f6i\u00e4n lopussa turvallisuuden yll\u00e4pit\u00e4miseksi.<\/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\">Tilan ilmaisin:<\/strong> Visuaalinen ikkuna tai kosketinl\u00e4ht\u00f6 toimintatilan n\u00e4ytt\u00e4miseksi.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"2559\" data-end=\"2582\"><strong data-start=\"2559\" data-end=\"2582\">Toimintaj\u00e4rjestys:<\/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\">Normaali tila:<\/strong> Suuri vastus, ei vaikutusta piiriin.<\/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-tapahtuma:<\/strong> J\u00e4nnite nousee Uc-kynnyksen yl\u00e4puolelle.<\/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\">Kiinnitys:<\/strong> SPD ohjaa ylij\u00e4nnitevirran maahan ja laskee j\u00e4nnitteen turvalliselle yl\u00f6s (j\u00e4nnitesuojaustasolle).<\/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\">Palautus:<\/strong> SPD palaa suuren vastuksen valmiustilaan.<\/p>\r\n<\/li>\r\n<\/ol>\r\n<h2 data-start=\"2889\" data-end=\"2940\">Tyypin 2 ylij\u00e4nnitesuojalaitteen toiminta<\/h2>\r\n<p data-start=\"2942\" data-end=\"3106\">Tyypin 2 ylij\u00e4nnitesuojalaitteen ensisijainen teht\u00e4v\u00e4 on rajoittaa transienttiylij\u00e4nnitteet tasolle, jonka alavirran laitteet kest\u00e4v\u00e4t vaurioitta.<\/p>\r\n<p data-start=\"3108\" data-end=\"3122\">T\u00e4rkeimm\u00e4t toiminnot:<\/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\">J\u00e4\u00e4nn\u00f6sj\u00e4nniterajoitus<\/strong> \u2014 v\u00e4hent\u00e4\u00e4 j\u00e4nnitett\u00e4 sen j\u00e4lkeen, kun tyypin 1 SPD on absorboinut suurimman osan energiasta.<\/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\">Ylij\u00e4nnitesuoja<\/strong> \u2014 v\u00e4hent\u00e4\u00e4 transientteja moottorin k\u00e4ynnistyksist\u00e4, pumpun kytkemisest\u00e4 tai muista induktiivisista kuormitustoiminnoista.<\/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\">Laitteiston suojaus<\/strong> \u2014 est\u00e4\u00e4 herk\u00e4n elektroniikan, PLC:iden, automaatioj\u00e4rjestelmien ja ohjauslaitteiden vaurioitumisen.<\/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\">J\u00e4rjestelm\u00e4n luotettavuus<\/strong> \u2014 v\u00e4hent\u00e4\u00e4 ylij\u00e4nniteh\u00e4iri\u00f6ist\u00e4 johtuvia seisokkeja.<\/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\">Osa kaskadista<\/strong> \u2014 sijaitsee palvelusuojan (tyyppi 1) ja k\u00e4ytt\u00f6pistelaitteiden (tyyppi 3) v\u00e4liss\u00e4.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"3666\" data-end=\"3716\">Tyypin 2 ylij\u00e4nnitesuojalaitteiden sovellukset<\/h2>\r\n<a href=\"https:\/\/www.britecelectric.com\/fi\/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\">Tyypin 2 SPD:t on asennettu:<\/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\">Teollisuustilat ukkossuojaj\u00e4rjestelmill\u00e4.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3811\" data-end=\"3891\">\r\n<p data-start=\"3813\" data-end=\"3891\">Liikerakennukset LVI-, hissien, valaistuksen ja IT-j\u00e4rjestelmien suojaamiseen.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3892\" data-end=\"3949\">\r\n<p data-start=\"3894\" data-end=\"3949\">Koneen ohjauskaapit teollisuusautomaatioon.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3950\" data-end=\"4034\">\r\n<p data-start=\"3952\" data-end=\"4034\">Uusiutuvat energiaj\u00e4rjestelm\u00e4t, kuten aurinkoenergian invertterit ja tuuliturbiinien ohjauslaitteet, edellytt\u00e4v\u00e4t vankkaa <a href=\"https:\/\/www.britecelectric.com\/fi\/product_category\/pv-surge-protection-type-2\/\" target=\"_blank\" rel=\"noopener\">ylij\u00e4nnitesuoja<\/a> (katso meid\u00e4n <strong><em><a class=\"\" href=\"https:\/\/www.britecelectric.com\/fi\/blog\/solar-surge-protection-devices-selection-guide\/\" target=\"_blank\" rel=\"noopener\" data-start=\"201\" data-end=\"334\">Aurinkosuojalaitteiden valintaopas<\/a><\/em><\/strong> ja <strong><em><a class=\"\" href=\"https:\/\/www.britecelectric.com\/fi\/blog\/surge-protection-for-solar-photovoltaic-systems\/\" target=\"_blank\" rel=\"noopener\" data-start=\"339\" data-end=\"474\">Ylij\u00e4nnitesuoja aurinkos\u00e4hk\u00f6j\u00e4rjestelmille<\/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\">Sairaalat ja datakeskukset, joissa k\u00e4ytt\u00f6aika on kriittinen.<\/p>\r\n<\/li>\r\n \t<li data-start=\"4094\" data-end=\"4151\">\r\n<p data-start=\"4096\" data-end=\"4151\">Asuinrakennusten p\u00e4\u00e4paneelit koko talon suojaamiseen.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"262\" data-end=\"316\">Tyypin 1, tyypin 2 ja tyypin 3 ylij\u00e4nnitesuojalaitteet<\/h2>\r\n<p data-start=\"318\" data-end=\"648\">Ylij\u00e4nnitesuojalaitteita on kolme p\u00e4\u00e4tyyppi\u00e4. Jokaisella tyypill\u00e4 on erilainen teht\u00e4v\u00e4 s\u00e4hk\u00f6j\u00e4rjestelm\u00e4ss\u00e4. Voit lukea lis\u00e4\u00e4 yksityiskohtaisesta oppaastamme t\u00e4\u00e4lt\u00e4: <em><strong><a class=\"\" href=\"https:\/\/www.britecelectric.com\/fi\/blog\/difference-between-type-1-type-2-and-type-3-surge-protective-devices\/\" target=\"_blank\" rel=\"noopener\" data-start=\"468\" data-end=\"647\">Ero tyypin 1, tyypin 2 ja tyypin 3 ylij\u00e4nnitesuojalaitteiden v\u00e4lill\u00e4<\/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>Ominaisuus<\/b><\/strong><\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\"><strong><b>Tyyppi 1 SPD<\/b><\/strong><\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\"><strong><b>Tyyppi 2 SPD<\/b><\/strong><\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\"><strong><b>Tyyppi 3 SPD<\/b><\/strong><\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Sijainti<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">Asennettu huoltoon.<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">Asennettu p\u00e4\u00e4jakokeskukseen.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">Asennettu l\u00e4helle herkki\u00e4 kuormia.<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Testaa aaltomuotoa<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">Testattu 10\/350 \u03bcs salamaimpulssilla.<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">Testattu 8\/20 \u03bcs ylij\u00e4nnitevirralla.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">Testattu j\u00e4nnitteell\u00e4 1,2\/50 \u03bcs + 8\/20 \u03bcs virralla.<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Tarkoitus<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">Purkaa suoraa salamavirtaa.<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">Rajoittaa j\u00e4\u00e4nn\u00f6spiikkej\u00e4 ja kytkent\u00e4piikkej\u00e4.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">Antaa lopullisen suojan elektroniikalle.<\/td>\r\n<\/tr>\r\n<tr>\r\n<td style=\"width: 20.4466%;\" width=\"142\">Tyypillinen yl\u00f6s<\/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\">Esimerkkej\u00e4<\/td>\r\n<td style=\"width: 25.0372%;\" width=\"142\">Rakennukset, joissa on ukkossuojaj\u00e4rjestelm\u00e4 (LPS).<\/td>\r\n<td style=\"width: 28.1389%;\" width=\"142\">Ohjauspaneelit ja alajakotaulut.<\/td>\r\n<td style=\"width: 58.2638%;\" width=\"142\">IT-laitteet ja kodin elektroniikka.<\/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\">Yhteenveto:<\/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\">Tyyppi 1 SPD<\/strong> pys\u00e4ytt\u00e4\u00e4 suurimman osan salaman aiheuttamasta korkeaenergisesta aallosta.<\/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\">Tyyppi 2 SPD<\/strong> on keskimm\u00e4inen puolustuslinja. Se v\u00e4hent\u00e4\u00e4 j\u00e4ljell\u00e4 olevaa ylij\u00e4nnitett\u00e4 ja ohjaa kytkent\u00e4piikkej\u00e4.<\/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\">Tyyppi 3 SPD<\/strong> on viimeinen askel. Se suojaa herkk\u00e4\u00e4 elektroniikkaa pienilt\u00e4, \u200b\u200bnopeilta j\u00e4nnitteilt\u00e4.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"4715\" data-end=\"4766\">Kuinka valita oikea ylij\u00e4nnitesuoja?<\/h2>\r\n<p data-start=\"4768\" data-end=\"4922\">Kun valitset parasta tyypin 2 ylij\u00e4nnitesuojalaitetta, valinnan tulee perustua j\u00e4rjestelm\u00e4n yhteensopivuuteen, ylij\u00e4nniteriskin tasoon ja laitteen herkkyyteen.<\/p>\r\n<p data-start=\"4924\" data-end=\"5057\"><strong data-start=\"4924\" data-end=\"4976\">1. Yhdist\u00e4 j\u00e4rjestelm\u00e4n j\u00e4nnite ja maadoitus<\/strong><br data-start=\"4976\" data-end=\"4979\" \/>Eri j\u00e4rjestelm\u00e4t \u2014 TT, TN-S, TN-C, IT \u2014 vaativat erilaisia \u200b\u200bSPD-kokoonpanoja:<\/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> (kaikkinapainen suojaus) TN-j\u00e4rjestelmille.<\/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> konfiguraatio (L-N-suojaus plus N-PE-moduuli) TT-j\u00e4rjestelmille N-PE-ylij\u00e4nnitetapahtumien k\u00e4sittelemiseksi.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"5214\" data-end=\"5404\"><strong data-start=\"5214\" data-end=\"5272\">2. M\u00e4\u00e4rit\u00e4 Uc (maksimi jatkuva k\u00e4ytt\u00f6j\u00e4nnite)<\/strong><br data-start=\"5272\" data-end=\"5275\" \/>Uc:n tulee olla hieman j\u00e4rjestelm\u00e4n nimellisj\u00e4nnitteen yl\u00e4puolella tarpeettoman laukaisun est\u00e4miseksi, mutta riitt\u00e4v\u00e4n alhainen tehokkaan suojauksen takaamiseksi.<\/p>\r\n<p data-start=\"5406\" data-end=\"5449\"><strong data-start=\"5406\" data-end=\"5447\">3. Tarkista purkausvirran kyky<\/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\">Nimellinen purkausvirta (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\">Suurin purkausvirta (Imax):<\/strong> 20\u201380 kA riskitasosta riippuen.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"5572\" data-end=\"5721\"><strong data-start=\"5572\" data-end=\"5608\">4. J\u00e4nnitteen suojaustaso (yl\u00f6s)<\/strong><br data-start=\"5608\" data-end=\"5611\" \/>Lower Up tarkoittaa parempaa suojausta \u2013 tavoite \u2264 2,5 kV yleislaitteille, \u2264 1,5 kV herk\u00e4lle elektroniikalle.<\/p>\r\n<p data-start=\"5723\" data-end=\"5862\"><strong data-start=\"5723\" data-end=\"5767\">5. Tilap\u00e4isen ylij\u00e4nnitteen (TOV) kesto<\/strong><br data-start=\"5767\" data-end=\"5770\" \/>Varmista, ett\u00e4 SPD kest\u00e4\u00e4 v\u00e4liaikaiset ylij\u00e4nniteolosuhteet vioista tai kytkent\u00e4tapahtumista.<\/p>\r\n<p data-start=\"5864\" data-end=\"5892\"><strong data-start=\"5864\" data-end=\"5890\">6. Lis\u00e4ominaisuudet<\/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\">Kytkett\u00e4v\u00e4t moduulit nopeaan huoltoon.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5936\" data-end=\"5975\">\r\n<p data-start=\"5938\" data-end=\"5975\">Et\u00e4h\u00e4lytyskoskettimet valvontaa varten.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5976\" data-end=\"6019\">\r\n<p data-start=\"5978\" data-end=\"6019\">L\u00e4mp\u00f6katkos ja visuaaliset ilmaisimet.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"6026\" data-end=\"6076\">Kuinka asentaa tyypin 2 ylij\u00e4nnitesuojalaite<\/h2>\r\n<a href=\"https:\/\/www.britecelectric.com\/fi\/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\">Asennusalan parhaat k\u00e4yt\u00e4nn\u00f6t kentt\u00e4suunnittelukokemuksesta:<\/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\">Sijainti<\/strong> \u2014 Asenna mahdollisimman l\u00e4helle p\u00e4\u00e4jakolevyn kiskoja tai laitteita, joita haluat suojata.<\/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\">Rinnakkaisliit\u00e4nt\u00e4<\/strong> \u2014 Tyypin 2 SPD:t kytket\u00e4\u00e4n yleens\u00e4 rinnan virtal\u00e4hteen kanssa.<\/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\">Johdon pituus<\/strong> \u2014 Pid\u00e4 vaihe-, nolla- ja maajohtimien yhteispituus alle 0,5 m, jotta suojaj\u00e4nnite ei nouse.<\/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\">Johtimen poikkileikkaus<\/strong> \u2014 V\u00e4hint\u00e4\u00e4n 6 mm\u00b2 kuparia tyypille 2; suurempia kokoja suurempikapasiteettisia laitteita varten.<\/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\">Maadoitus<\/strong> \u2014 Liit\u00e4 suoraan p\u00e4\u00e4potentiaalintasaustankoon lyhimm\u00e4ll\u00e4 tiell\u00e4.<\/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\">Ylivirtasuojaus<\/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\">Koordinointi kaskadij\u00e4rjestelmiss\u00e4<\/strong> \u2014 Jos asennetaan tyypin 1 SPD:n j\u00e4lkeen, s\u00e4ilyt\u00e4 et\u00e4isyys (&gt; 10 m) tai asenna irrotusinduktori varmistaaksesi oikean energian jaon.<\/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\">J\u00e4rjestelm\u00e4kohtainen johdotus<\/strong> \u2014 Sis\u00e4llyt\u00e4 TT-j\u00e4rjestelmiin N-PE-suojamoduuli, joka k\u00e4sittelee nolla-maa-piikit.<\/p>\r\n<\/li>\r\n<\/ol>\r\n<p data-start=\"7147\" data-end=\"7255\">N\u00e4iden ohjeiden noudattaminen varmistaa, ett\u00e4 SPD toimii spesifikaatioiden mukaisesti ja on s\u00e4hk\u00f6standardien mukainen.<\/p>\r\n\r\n<h2 data-start=\"7262\" data-end=\"7275\">Johtop\u00e4\u00e4t\u00f6s<\/h2>\r\n<p data-start=\"7277\" data-end=\"7508\">A <em><a href=\"https:\/\/www.britecelectric.com\/fi\/product-category\/ac-power-surge-protection\/type-2-surge-protective-device\/\" target=\"_blank\" rel=\"noopener\"><strong data-start=\"7279\" data-end=\"7313\">Tyypin 2 ylij\u00e4nnitesuojalaite<\/strong><\/a><\/em> on t\u00e4rke\u00e4 elementti kerroksellisessa s\u00e4hk\u00f6suojauksessa. Se suojaa salaman ja sis\u00e4isten kytkent\u00e4tapahtumien j\u00e4\u00e4nn\u00f6spiikeilt\u00e4, \u200b\u200bmik\u00e4 varmistaa laitteiden pitk\u00e4n k\u00e4ytt\u00f6i\u00e4n ja toiminnan vakauden.<\/p>\r\n<p data-start=\"7510\" data-end=\"7767\">Ymm\u00e4rt\u00e4m\u00e4ll\u00e4 sen toimintaperiaatteen, asennuss\u00e4\u00e4nn\u00f6t ja valintaparametrit, insin\u00f6\u00f6rit ja hankintap\u00e4\u00e4llik\u00f6t voivat m\u00e4\u00e4ritt\u00e4\u00e4 laitteet, jotka t\u00e4ytt\u00e4v\u00e4t j\u00e4rjestelm\u00e4vaatimukset, ovat IEC\/EN 61643-11 mukaisia \u200b\u200bja tarjoavat luotettavan suojan vuosiksi eteenp\u00e4in.<\/p>\r\n<p data-start=\"7769\" data-end=\"7951\">Oikein asennettu tyypin 2 SPD ei ole vain komponentti \u2013 se on s\u00e4hk\u00f6j\u00e4rjestelm\u00e4si vakuutus. Lis\u00e4tietoja: <strong><em><a class=\"\" href=\"https:\/\/www.britecelectric.com\/fi\/blog\/surge-protection-for-solar-photovoltaic-systems\/\" target=\"_blank\" rel=\"noopener\" data-start=\"1609\" data-end=\"1719\">aurinkoenergian SPD-sovellukset<\/a><\/em><\/strong> ja kuinka valita oikea.<\/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\/fi\/wp-json\/wp\/v2\/blog\/2154","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.britecelectric.com\/fi\/wp-json\/wp\/v2\/blog"}],"about":[{"href":"https:\/\/www.britecelectric.com\/fi\/wp-json\/wp\/v2\/types\/blog"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.britecelectric.com\/fi\/wp-json\/wp\/v2\/media\/2160"}],"wp:attachment":[{"href":"https:\/\/www.britecelectric.com\/fi\/wp-json\/wp\/v2\/media?parent=2154"}],"wp:term":[{"taxonomy":"blog_category","embeddable":true,"href":"https:\/\/www.britecelectric.com\/fi\/wp-json\/wp\/v2\/blog_category?post=2154"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}