{"id":2176,"date":"2025-08-26T10:11:09","date_gmt":"2025-08-26T02:11:09","guid":{"rendered":"https:\/\/www.britecelectric.com\/?post_type=blog&#038;p=2176"},"modified":"2025-08-26T10:16:08","modified_gmt":"2025-08-26T02:16:08","slug":"how-to-choose-single-phase-surge-protection-device","status":"publish","type":"blog","link":"https:\/\/www.britecelectric.com\/pt\/blog\/how-to-choose-single-phase-surge-protection-device\/","title":{"rendered":"Como escolher um dispositivo de prote\u00e7\u00e3o contra surtos monof\u00e1sico?"},"content":{"rendered":"<h2 data-start=\"474\" data-end=\"492\">Introdu\u00e7\u00e3o<\/h2>\r\n<p data-start=\"493\" data-end=\"937\">Os surtos s\u00e3o uma das amea\u00e7as mais subestimadas nos sistemas el\u00e9tricos. Uma sobretens\u00e3o repentina, seja causada por raios, comuta\u00e7\u00e3o da rede ou at\u00e9 mesmo equipamento interno, pode degradar o isolamento, desarmar disjuntores ou destruir dispositivos sens\u00edveis num instante. Um dispositivo de prote\u00e7\u00e3o contra surtos monof\u00e1sico (SPD) \u00e9 a primeira linha de defesa. Ele desvia o excesso de energia para a terra e garante que a tens\u00e3o que chega ao seu equipamento permane\u00e7a dentro de limites seguros.<\/p>\r\n<p data-start=\"939\" data-end=\"1244\">Para engenheiros el\u00e9tricos e especialistas em compras, o desafio n\u00e3o \u00e9 usar um SPD monof\u00e1sico, mas como escolher o correto. Este guia fornece uma abordagem clara, t\u00e9cnica e pr\u00e1tica que combina padr\u00f5es internacionais, melhores pr\u00e1ticas de engenharia e experi\u00eancia do mundo real.<\/p>\r\n\r\n<h2 data-start=\"1251\" data-end=\"1304\">O que \u00e9 um dispositivo de prote\u00e7\u00e3o contra surtos monof\u00e1sico?<\/h2>\r\n<p data-start=\"1305\" data-end=\"1604\">Um dispositivo de prote\u00e7\u00e3o contra surtos monof\u00e1sico \u00e9 instalado em sistemas CA monof\u00e1sicos de 230\/240 V para prote\u00e7\u00e3o contra sobretens\u00f5es transit\u00f3rias. Ele opera permanecendo passivo sob tens\u00e3o normal, mas assim que ocorre um surto, ele se torna um caminho de baixa imped\u00e2ncia e redireciona a corrente de surto para o terra.<\/p>\r\n<p data-start=\"1606\" data-end=\"1905\">Os dispositivos de prote\u00e7\u00e3o monof\u00e1sicos s\u00e3o amplamente aplicados em quadros de distribui\u00e7\u00e3o residenciais, edif\u00edcios comerciais, sistemas solares fotovoltaicos e pain\u00e9is de controle industriais. Em cada caso, prolongam a vida \u00fatil do equipamento, reduzem o tempo de inatividade e garantem a conformidade com os modernos requisitos de seguran\u00e7a.<\/p>\r\n<p data-start=\"1606\" data-end=\"1905\"><a href=\"https:\/\/www.britecelectric.com\/pt\/blog\/how-to-choose-single-phase-surge-protection-device\/attachment\/br-20-4p-1type-2-surge-protection-device-jpg-3\/\" rel=\"attachment wp-att-2177\"><img class=\"alignnone wp-image-2177\" src=\"https:\/\/www.britecelectric.com\/wp-content\/uploads\/2025\/08\/BR-20-4P-1Type-2-Surge-Protection-Device.jpg-2-1024x1024.webp\" alt=\"\" width=\"914\" height=\"914\" \/><\/a><\/p>\r\n\r\n<h2 data-start=\"1912\" data-end=\"1954\">Padr\u00f5es IEC e classifica\u00e7\u00e3o SPD<\/h2>\r\n<p data-start=\"1955\" data-end=\"2192\">A sele\u00e7\u00e3o de um dispositivo de prote\u00e7\u00e3o contra surtos monof\u00e1sico deve estar alinhada \u00e0s normas internacionais, principalmente <a href=\"https:\/\/webstore.iec.ch\/en\/publication\/5682\" target=\"_blank\" rel=\"noopener\"><strong data-start=\"2071\" data-end=\"2087\">CEI 61643-11<\/strong><\/a> e <a href=\"http:\/\/IEC 61643-11\" target=\"_blank\" rel=\"noopener\"><strong data-start=\"2092\" data-end=\"2108\">CEI 61643-12<\/strong><\/a>. Eles definem as formas de onda de teste, classifica\u00e7\u00e3o e diretrizes de instala\u00e7\u00e3o:<\/p>\r\n\r\n<ul data-start=\"2194\" data-end=\"2680\">\r\n \t<li data-start=\"2194\" data-end=\"2394\">\r\n<p data-start=\"2196\" data-end=\"2394\"><strong data-start=\"2196\" data-end=\"2210\">Tipo 1 SPD<\/strong>: Testado com forma de onda 10\/350 \u00b5s, projetado para suportar correntes diretas de raios. Instalado na entrada de servi\u00e7o onde existam linhas a\u00e9reas ou sistemas de prote\u00e7\u00e3o contra raios.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2395\" data-end=\"2546\">\r\n<p data-start=\"2397\" data-end=\"2546\"><strong data-start=\"2397\" data-end=\"2411\">Tipo 2 SPD<\/strong>: Testado com forma de onda de 8\/20 \u00b5s, protege contra surtos de comuta\u00e7\u00e3o e raios indiretos. Normalmente instalado em pain\u00e9is de distribui\u00e7\u00e3o.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2547\" data-end=\"2680\">\r\n<p data-start=\"2549\" data-end=\"2680\"><strong data-start=\"2549\" data-end=\"2563\">Tipo 3 SPD<\/strong>: Instalado pr\u00f3ximo a cargas sens\u00edveis, garante baix\u00edssima tens\u00e3o residual (Up). Usado como \u00faltimo est\u00e1gio de prote\u00e7\u00e3o.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"2682\" data-end=\"2841\">Se voc\u00ea quiser se aprofundar na classifica\u00e7\u00e3o detalhada dos SPDs e como cada tipo \u00e9 definido em padr\u00f5es e aplica\u00e7\u00f5es pr\u00e1ticas, voc\u00ea pode explorar nosso artigo dedicado aqui: <span style=\"text-decoration: underline; font-size: 20px;\"><a class=\"decorated-link\" href=\"https:\/\/www.britecelectric.com\/pt\/blog\/classification-of-spds\/\" target=\"_blank\" rel=\"noopener\" data-start=\"1210\" data-end=\"1295\"><em><strong>Classifica\u00e7\u00e3o dos SPD<\/strong><\/em><\/a>.<\/span><\/p>\r\n\r\n<h2 data-start=\"2848\" data-end=\"2880\">Par\u00e2metros principais a serem considerados<\/h2>\r\n<p data-start=\"2881\" data-end=\"2984\">Ao comparar diferentes SPDs monof\u00e1sicos, v\u00e1rios par\u00e2metros s\u00e3o cr\u00edticos para a sele\u00e7\u00e3o adequada:<\/p>\r\n\r\n<ul data-start=\"2986\" data-end=\"3881\">\r\n \t<li data-start=\"2986\" data-end=\"3181\">\r\n<p data-start=\"2988\" data-end=\"3181\"><strong data-start=\"2988\" data-end=\"3033\">Uc (Tens\u00e3o M\u00e1xima de Opera\u00e7\u00e3o Cont\u00ednua)<\/strong>: A tens\u00e3o RMS m\u00e1xima que o dispositivo pode suportar sem degrada\u00e7\u00e3o. Para sistemas 230\/240 V, o valor padr\u00e3o \u00e9 275 Vca entre linha e neutro.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3182\" data-end=\"3307\">\r\n<p data-start=\"3184\" data-end=\"3307\"><strong data-start=\"3184\" data-end=\"3217\">Acima (n\u00edvel de prote\u00e7\u00e3o de tens\u00e3o)<\/strong>: A tens\u00e3o fixada durante um surto. A eletr\u00f4nica sens\u00edvel requer acima de 1,5\u20132,5 kV.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3308\" data-end=\"3473\">\r\n<p data-start=\"3310\" data-end=\"3473\"><strong data-start=\"3310\" data-end=\"3344\">In (corrente de descarga nominal)<\/strong>: A corrente que o SPD pode descarregar repetidamente sem falha. Um bom SPD monof\u00e1sico deve suportar pelo menos 20 kA (8\/20 \u00b5s).<\/p>\r\n<\/li>\r\n \t<li data-start=\"3474\" data-end=\"3601\">\r\n<p data-start=\"3476\" data-end=\"3601\"><strong data-start=\"3476\" data-end=\"3512\">Imax (corrente m\u00e1xima de descarga)<\/strong>: A corrente m\u00e1xima que o SPD pode suportar em um \u00fanico evento, normalmente 40 kA ou mais.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3602\" data-end=\"3759\">\r\n<p data-start=\"3604\" data-end=\"3759\"><strong data-start=\"3604\" data-end=\"3630\">Iimp (corrente de impulso)<\/strong>: Espec\u00edfico para SPDs Tipo 1, testado com forma de onda 10\/350 \u00b5s. Os valores come\u00e7am em 12,5 kA, sendo 25 kA recomendados em \u00e1reas de alto risco.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3760\" data-end=\"3881\">\r\n<p data-start=\"3762\" data-end=\"3881\"><strong data-start=\"3762\" data-end=\"3779\">Tempo de resposta<\/strong>: os SPDs atuam em nanossegundos. Quanto mais r\u00e1pida a rea\u00e7\u00e3o, melhor prote\u00e7\u00e3o para componentes eletr\u00f4nicos sens\u00edveis.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"3883\" data-end=\"4010\">Esses par\u00e2metros devem sempre corresponder ao n\u00edvel de exposi\u00e7\u00e3o do sistema, tipo de aterramento e categoria de isolamento do equipamento.<\/p>\r\n\r\n<h2 data-start=\"4017\" data-end=\"4064\">Configura\u00e7\u00f5es de aterramento e fia\u00e7\u00e3o do sistema<\/h2>\r\n<p data-start=\"4065\" data-end=\"4202\">O tipo de aterramento \u00e9 muitas vezes esquecido, mas \u00e9 um dos fatores mais decisivos na escolha de um dispositivo de prote\u00e7\u00e3o contra surtos monof\u00e1sico.<\/p>\r\n\r\n<ul data-start=\"4204\" data-end=\"4774\">\r\n \t<li data-start=\"4204\" data-end=\"4497\">\r\n<p data-start=\"4206\" data-end=\"4497\"><strong data-start=\"4206\" data-end=\"4220\">TT Sistemas<\/strong>: Requer 1P+N (tamb\u00e9m chamado de 1+1) SPD. Esta configura\u00e7\u00e3o utiliza prote\u00e7\u00e3o MOV entre linha e neutro, al\u00e9m de um centelhador ou elemento dedicado entre neutro e PE. Garante descarga controlada para a terra, o que \u00e9 vital em TT, onde o potencial neutro pode aumentar durante faltas.<\/p>\r\n<\/li>\r\n \t<li data-start=\"4498\" data-end=\"4670\">\r\n<p data-start=\"4500\" data-end=\"4670\"><strong data-start=\"4500\" data-end=\"4526\">Sistemas TN-S ou TN-C-S<\/strong>: Pode usar 1P ou 1P+N dependendo do design do quadro de distribui\u00e7\u00e3o. Os caminhos linha-neutro e linha-terra devem ser protegidos.<\/p>\r\n<\/li>\r\n \t<li data-start=\"4671\" data-end=\"4774\">\r\n<p data-start=\"4673\" data-end=\"4774\"><strong data-start=\"4673\" data-end=\"4689\">Sistemas TN-C<\/strong>: Geralmente aplicam SPDs 1P ou 2P dependendo se o condutor PEN est\u00e1 acess\u00edvel.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"4776\" data-end=\"5017\">Para todos os sistemas, as regras de liga\u00e7\u00e3o permanecem as mesmas: mantenha a liga\u00e7\u00e3o \u00e0 terra do SPD o mais curta poss\u00edvel, idealmente inferior a 0,5 m. Cabos longos aumentam a indut\u00e2ncia e, portanto, aumentam a tens\u00e3o residual que o dispositivo protegido ver\u00e1.<\/p>\r\n\r\n<h2 data-start=\"5024\" data-end=\"5058\">Guia de sele\u00e7\u00e3o passo a passo<\/h2>\r\n<p data-start=\"5060\" data-end=\"5255\">Este \u00e9 o cerne do processo de tomada de decis\u00e3o. Muitos engenheiros e compradores pesquisam especificamente como escolher um SPD monof\u00e1sico, portanto, esta se\u00e7\u00e3o fornece um roteiro pr\u00e1tico e detalhado:<\/p>\r\n\r\n<h3 data-start=\"5257\" data-end=\"5559\"><strong data-start=\"5257\" data-end=\"5295\">Etapa 1: avaliar risco e exposi\u00e7\u00e3o<\/strong><\/h3>\r\n<p data-start=\"5257\" data-end=\"5559\">Determine se o edif\u00edcio possui sistema externo de prote\u00e7\u00e3o contra raios (LPS) ou \u00e9 alimentado por linhas a\u00e9reas. Se sim, \u00e9 obrigat\u00f3rio um SPD Tipo 1 na entrada de servi\u00e7o. Para abastecimento subterr\u00e2neo em \u00e1reas de baixo risco, um Tipo 2 de alta capacidade pode ser suficiente.<\/p>\r\n\r\n<h3 data-start=\"5561\" data-end=\"5803\"><strong data-start=\"5561\" data-end=\"5601\">Etapa 2: Identifique o sistema de aterramento<\/strong><\/h3>\r\n<p data-start=\"5561\" data-end=\"5803\">Verifique se sua instala\u00e7\u00e3o \u00e9 TT, TN-S, TN-C-S ou TN-C. Isso determina se voc\u00ea precisa de um SPD 1P, um SPD 1P+N ou um SPD 2P. Selecionar a configura\u00e7\u00e3o de fia\u00e7\u00e3o errada pode tornar o SPD ineficaz.<\/p>\r\n\r\n<h3 data-start=\"5805\" data-end=\"5846\"><strong data-start=\"5805\" data-end=\"5844\">Etapa 3: Definir o Est\u00e1gio de Prote\u00e7\u00e3o<\/strong><\/h3>\r\n<ul data-start=\"5847\" data-end=\"6077\">\r\n \t<li data-start=\"5847\" data-end=\"5908\">\r\n<p data-start=\"5849\" data-end=\"5908\">Na entrada de servi\u00e7o: SPD Tipo 1 ou Tipo 1+2 combinado.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5909\" data-end=\"5978\">\r\n<p data-start=\"5911\" data-end=\"5978\">Nos pain\u00e9is de distribui\u00e7\u00e3o: Tipo 2, com In \u2265 20 kA e Imax \u2265 40 kA.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5979\" data-end=\"6077\">\r\n<p data-start=\"5981\" data-end=\"6077\">Em cargas sens\u00edveis: Tipo 3, para reduzir Up abaixo da resist\u00eancia de isolamento de dispositivos eletr\u00f4nicos.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h3 data-start=\"6079\" data-end=\"6159\"><strong data-start=\"6079\" data-end=\"6115\">Etapa 4: selecione as classifica\u00e7\u00f5es t\u00e9cnicas<\/strong><\/h3>\r\n<p data-start=\"6079\" data-end=\"6159\">Combine as classifica\u00e7\u00f5es do SPD com o seu sistema:<\/p>\r\n\r\n<ul data-start=\"6160\" data-end=\"6369\">\r\n \t<li data-start=\"6160\" data-end=\"6197\">\r\n<p data-start=\"6162\" data-end=\"6197\">Uc: 275 Vca para sistemas 230\/240 V.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6198\" data-end=\"6304\">\r\n<p data-start=\"6200\" data-end=\"6304\">Acima: Deve ser inferior \u00e0 categoria de isolamento do equipamento (IEC 60664: Cat II \u2248 2,5 kV, Cat III \u2248 4 kV).<\/p>\r\n<\/li>\r\n \t<li data-start=\"6305\" data-end=\"6369\">\r\n<p data-start=\"6307\" data-end=\"6369\">In\/Imax\/Iimp: De acordo com n\u00edvel de instala\u00e7\u00e3o e zona de risco.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h3 data-start=\"6371\" data-end=\"6689\"><strong data-start=\"6371\" data-end=\"6415\">Etapa 5: Planeje a coordena\u00e7\u00e3o entre as etapas<\/strong><\/h3>\r\n<p data-start=\"6371\" data-end=\"6689\">Os SPDs devem trabalhar juntos. O dispositivo a montante deve absorver energia sem passar tens\u00e3o destrutiva a jusante, enquanto o SPD a jusante ajusta a prote\u00e7\u00e3o. Mantenha pelo menos 10 metros entre os dispositivos ou insira indut\u00e2ncia de desacoplamento para garantir o compartilhamento adequado de energia.<\/p>\r\n\r\n<h3 data-start=\"6691\" data-end=\"6928\"><strong data-start=\"6691\" data-end=\"6739\">Etapa 6: Garanta a prote\u00e7\u00e3o adequada contra sobrecorrente<\/strong><\/h3>\r\n<p data-start=\"6691\" data-end=\"6928\">Todo SPD requer prote\u00e7\u00e3o de backup. A menos que o SPD inclua um fus\u00edvel integrado, instale um MCB ou fus\u00edvel em s\u00e9rie. Isto evita eventos de curto-circuito quando o SPD atinge o fim da vida \u00fatil.<\/p>\r\n\r\n<h3 data-start=\"6930\" data-end=\"7027\"><strong data-start=\"6930\" data-end=\"6979\">Etapa 7: Considere a vida \u00fatil e a manuten\u00e7\u00e3o<\/strong><\/h3>\r\n<p data-start=\"6930\" data-end=\"7027\">Os SPDs degradam com o tempo. Escolha modelos com:<\/p>\r\n\r\n<ul data-start=\"7028\" data-end=\"7241\">\r\n \t<li data-start=\"7028\" data-end=\"7093\">\r\n<p data-start=\"7030\" data-end=\"7093\">Janelas de indica\u00e7\u00e3o de status que mostram condi\u00e7\u00f5es verdes\/vermelhas.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7094\" data-end=\"7162\">\r\n<p data-start=\"7096\" data-end=\"7162\">Contatos de sinaliza\u00e7\u00e3o remota para monitoramento em sistemas de controle.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7163\" data-end=\"7241\">\r\n<p data-start=\"7165\" data-end=\"7241\">M\u00f3dulos plug-in substitu\u00edveis, portanto a manuten\u00e7\u00e3o n\u00e3o requer nova fia\u00e7\u00e3o.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"7243\" data-end=\"7418\">Seguir este processo passo a passo garante que seu SPD monof\u00e1sico n\u00e3o seja apenas classificado corretamente, mas tamb\u00e9m instalado e mantido corretamente para confiabilidade a longo prazo.<\/p>\r\n\r\n<h2 data-start=\"7425\" data-end=\"7476\">Dicas pr\u00e1ticas de instala\u00e7\u00e3o e erros comuns<\/h2>\r\n<p data-start=\"7478\" data-end=\"7602\">Mesmo os melhores dispositivos de prote\u00e7\u00e3o monof\u00e1sicos falhar\u00e3o se instalados incorretamente. Siga estes princ\u00edpios de engenharia:<\/p>\r\n\r\n<ul data-start=\"7604\" data-end=\"7913\">\r\n \t<li data-start=\"7604\" data-end=\"7653\">\r\n<p data-start=\"7606\" data-end=\"7653\">Mantenha os cabos curtos e diretos, menos de 0,5 m.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7654\" data-end=\"7716\">\r\n<p data-start=\"7656\" data-end=\"7716\">Separe os cabos de alimenta\u00e7\u00e3o e de sinal para evitar surtos de acoplamento.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7717\" data-end=\"7769\">\r\n<p data-start=\"7719\" data-end=\"7769\">N\u00e3o agrupe os cabos SPD com circuitos protegidos.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7770\" data-end=\"7844\">\r\n<p data-start=\"7772\" data-end=\"7844\">Sempre conecte o aterramento do SPD \u00e0 barra de liga\u00e7\u00e3o equipotencial mais pr\u00f3xima.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7845\" data-end=\"7913\">\r\n<p data-start=\"7847\" data-end=\"7913\">Respeite as dist\u00e2ncias de coordena\u00e7\u00e3o entre os diferentes est\u00e1gios do SPD.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"7915\" data-end=\"8130\">Erros comuns incluem instalar apenas um est\u00e1gio, esquecer a prote\u00e7\u00e3o N-PE em sistemas TT ou superdimensionar SPDs sem necessidade real. Cada um deles reduz a efici\u00eancia da prote\u00e7\u00e3o e aumenta os custos sem benef\u00edcios.<\/p>\r\n\r\n<h2 data-start=\"8137\" data-end=\"8163\">Exemplos de aplicativos<\/h2>\r\n<ul data-start=\"8165\" data-end=\"8850\">\r\n \t<li data-start=\"8165\" data-end=\"8343\">\r\n<p data-start=\"8167\" data-end=\"8343\"><strong data-start=\"8167\" data-end=\"8195\">Aplica\u00e7\u00f5es residenciais<\/strong>: Um SPD Tipo 2 (em 20 kA, Imax 40 kA, Up &lt; 1,5 kV) instalado no quadro de distribui\u00e7\u00e3o principal protege os eletr\u00f4nicos dom\u00e9sticos contra dist\u00farbios da rede.<\/p>\r\n<\/li>\r\n \t<li data-start=\"8344\" data-end=\"8498\">\r\n<p data-start=\"8346\" data-end=\"8498\"><strong data-start=\"8346\" data-end=\"8370\">Edif\u00edcios Comerciais<\/strong>: Um DPS Tipo 1+2 no quadro principal combinado com DPS Tipo 2 nos pain\u00e9is de distribui\u00e7\u00e3o de piso garantem a continuidade do servi\u00e7o.<\/p>\r\n<\/li>\r\n \t<li data-start=\"8499\" data-end=\"8673\">\r\n<p data-start=\"8501\" data-end=\"8673\"><strong data-start=\"8501\" data-end=\"8526\">Instala\u00e7\u00f5es Industriais<\/strong>: SPDs Tipo 1 com classifica\u00e7\u00e3o de 25 kA Iimp na entrada de servi\u00e7o, com SPDs Tipo 2 coordenados em centros de controle de motores e SPDs Tipo 3 protegendo CLPs.<\/p>\r\n<\/li>\r\n \t<li data-start=\"8674\" data-end=\"8850\">\r\n<p data-start=\"8676\" data-end=\"8850\"><strong data-start=\"8676\" data-end=\"8696\">Sistemas solares fotovoltaicos<\/strong>: No lado CC, use SPDs com classifica\u00e7\u00e3o fotovoltaica. No lado CA, um SPD monof\u00e1sico Tipo 2 na sa\u00edda do inversor protege tanto o inversor quanto a interface da rede.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"8857\" data-end=\"8873\">Conclus\u00e3o<\/h2>\r\n<p data-start=\"8875\" data-end=\"9090\">Escolher o dispositivo de prote\u00e7\u00e3o contra surtos monof\u00e1sico certo requer mais do que apenas digitalizar uma folha de dados. Significa compreender o seu sistema, avaliar riscos, aplicar padr\u00f5es IEC e combinar par\u00e2metros cuidadosamente.<\/p>\r\n\r\n<ul data-start=\"9092\" data-end=\"9348\">\r\n \t<li data-start=\"9092\" data-end=\"9151\">\r\n<p data-start=\"9094\" data-end=\"9151\">Na entrada proteja contra raios com Tipo 1.<\/p>\r\n<\/li>\r\n \t<li data-start=\"9152\" data-end=\"9203\">\r\n<p data-start=\"9154\" data-end=\"9203\">Na distribui\u00e7\u00e3o, conte com dispositivos robustos do Tipo 2.<\/p>\r\n<\/li>\r\n \t<li data-start=\"9204\" data-end=\"9266\">\r\n<p data-start=\"9206\" data-end=\"9266\">Para componentes eletr\u00f4nicos sens\u00edveis, adicione o Tipo 3 no ponto de uso.<\/p>\r\n<\/li>\r\n \t<li data-start=\"9267\" data-end=\"9348\">\r\n<p data-start=\"9269\" data-end=\"9348\">Sempre respeite seu sistema de aterramento, pr\u00e1ticas de fia\u00e7\u00e3o e necessidades de manuten\u00e7\u00e3o.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"9350\" data-end=\"9539\">Ao aplicar estes princ\u00edpios, os engenheiros el\u00e9tricos e os profissionais de compras podem garantir que os seus sistemas n\u00e3o s\u00f3 est\u00e3o em conformidade, mas tamb\u00e9m s\u00e3o resilientes, econ\u00f3micos e preparados para o futuro.<\/p>","protected":false},"featured_media":2175,"parent":0,"menu_order":120,"template":"","meta":{"_acf_changed":false},"blog_category":[8],"class_list":["post-2176","blog","type-blog","status-publish","has-post-thumbnail","hentry","blog_category-company-news"],"acf":{"des":"This blog provides a comprehensive guide on how to choose Single-Phase Surge Protection Devices for residential, commercial, and industrial applications. It explains SPD classifications under IEC standards, technical parameters like Uc, Up, In, Imax, and Iimp, wiring configurations for TT and TN systems, and a detailed step-by-step selection process. With practical installation tips and real-world application cases, the article offers engineers and procurement specialists actionable insights to ensure reliable surge protection.","txt":"<h2 data-start=\"474\" data-end=\"492\">Introduction<\/h2>\r\n<p data-start=\"493\" data-end=\"937\">Surges are one of the most underestimated threats in electrical systems. A sudden overvoltage, whether caused by lightning, grid switching, or even internal equipment, can degrade insulation, trip breakers, or destroy sensitive devices in an instant. A Single-Phase Surge Protection Device (SPD) is the first line of defense. It diverts excess energy to earth and ensures that the voltage reaching your equipment stays within safe limits.<\/p>\r\n<p data-start=\"939\" data-end=\"1244\">For electrical engineers and procurement specialists, the challenge is not whether to use a single phase SPD, but how to choose the right one. This guide provides a clear, technical, and practical approach that combines international standards, engineering best practices, and real-world experience.<\/p>\r\n\r\n<h2 data-start=\"1251\" data-end=\"1304\">What is a Single-Phase Surge Protection Device?<\/h2>\r\n<p data-start=\"1305\" data-end=\"1604\">A Single-Phase Surge Protection Device is installed in 230\/240V single-phase AC systems to guard against transient overvoltages. It operates by remaining passive under normal voltage, but as soon as a surge occurs, it becomes a low-impedance path and redirects the surge current to the ground.<\/p>\r\n<p data-start=\"1606\" data-end=\"1905\">Single phase protection devices are widely applied in residential distribution boards, commercial buildings, solar photovoltaic systems, and industrial control panels. In each case, they extend the lifetime of equipment, reduce downtime, and provide compliance with modern safety requirements.<\/p>\r\n<p data-start=\"1606\" data-end=\"1905\"><a href=\"https:\/\/www.britecelectric.com\/blog\/how-to-choose-single-phase-surge-protection-device\/attachment\/br-20-4p-1type-2-surge-protection-device-jpg-3\/\" rel=\"attachment wp-att-2177\"><img class=\"alignnone wp-image-2177\" src=\"https:\/\/www.britecelectric.com\/wp-content\/uploads\/2025\/08\/BR-20-4P-1Type-2-Surge-Protection-Device.jpg-2-1024x1024.webp\" alt=\"\" width=\"914\" height=\"914\" \/><\/a><\/p>\r\n\r\n<h2 data-start=\"1912\" data-end=\"1954\">IEC Standards and SPD Classification<\/h2>\r\n<p data-start=\"1955\" data-end=\"2192\">The selection of a surge protection device single phase must be aligned with international standards, primarily <a href=\"https:\/\/webstore.iec.ch\/en\/publication\/5682\" target=\"_blank\" rel=\"noopener\"><strong data-start=\"2071\" data-end=\"2087\">IEC 61643-11<\/strong><\/a> and <a href=\"http:\/\/IEC 61643-11\" target=\"_blank\" rel=\"noopener\"><strong data-start=\"2092\" data-end=\"2108\">IEC 61643-12<\/strong><\/a>. These define the testing waveforms, classification, and installation guidelines:<\/p>\r\n\r\n<ul data-start=\"2194\" data-end=\"2680\">\r\n \t<li data-start=\"2194\" data-end=\"2394\">\r\n<p data-start=\"2196\" data-end=\"2394\"><strong data-start=\"2196\" data-end=\"2210\">Type 1 SPD<\/strong>: Tested with 10\/350 \u00b5s waveform, designed to withstand direct lightning currents. Installed at the service entrance where overhead lines or lightning protection systems are present.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2395\" data-end=\"2546\">\r\n<p data-start=\"2397\" data-end=\"2546\"><strong data-start=\"2397\" data-end=\"2411\">Type 2 SPD<\/strong>: Tested with 8\/20 \u00b5s waveform, protects against switching surges and indirect lightning. Typically installed in distribution panels.<\/p>\r\n<\/li>\r\n \t<li data-start=\"2547\" data-end=\"2680\">\r\n<p data-start=\"2549\" data-end=\"2680\"><strong data-start=\"2549\" data-end=\"2563\">Type 3 SPD<\/strong>: Installed close to sensitive loads, ensures very low residual voltage (Up). Used as the last stage of protection.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"2682\" data-end=\"2841\">If you want a deeper dive into the detailed classification of SPDs and how each type is defined in standards and practical applications, you can explore our dedicated article here: <span style=\"text-decoration: underline; font-size: 20px;\"><a class=\"decorated-link\" href=\"https:\/\/www.britecelectric.com\/blog\/classification-of-spds\/\" target=\"_blank\" rel=\"noopener\" data-start=\"1210\" data-end=\"1295\"><em><strong>Classification of SPDs<\/strong><\/em><\/a>.<\/span><\/p>\r\n\r\n<h2 data-start=\"2848\" data-end=\"2880\">Key Parameters to Consider<\/h2>\r\n<p data-start=\"2881\" data-end=\"2984\">When comparing different single phase SPDs, several parameters are critical for proper selection:<\/p>\r\n\r\n<ul data-start=\"2986\" data-end=\"3881\">\r\n \t<li data-start=\"2986\" data-end=\"3181\">\r\n<p data-start=\"2988\" data-end=\"3181\"><strong data-start=\"2988\" data-end=\"3033\">Uc (Maximum Continuous Operating Voltage)<\/strong>: The maximum RMS voltage the device can handle without degradation. For 230\/240V systems, the standard value is 275V AC between line and neutral.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3182\" data-end=\"3307\">\r\n<p data-start=\"3184\" data-end=\"3307\"><strong data-start=\"3184\" data-end=\"3217\">Up (Voltage Protection Level)<\/strong>: The clamped voltage during a surge. Sensitive electronics require Up below 1.5\u20132.5 kV.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3308\" data-end=\"3473\">\r\n<p data-start=\"3310\" data-end=\"3473\"><strong data-start=\"3310\" data-end=\"3344\">In (Nominal Discharge Current)<\/strong>: The current the SPD can discharge repeatedly without failure. A good single-phase SPD should handle at least 20 kA (8\/20 \u00b5s).<\/p>\r\n<\/li>\r\n \t<li data-start=\"3474\" data-end=\"3601\">\r\n<p data-start=\"3476\" data-end=\"3601\"><strong data-start=\"3476\" data-end=\"3512\">Imax (Maximum Discharge Current)<\/strong>: The maximum current the SPD can withstand in a single event, typically 40 kA or more.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3602\" data-end=\"3759\">\r\n<p data-start=\"3604\" data-end=\"3759\"><strong data-start=\"3604\" data-end=\"3630\">Iimp (Impulse Current)<\/strong>: Specific for Type 1 SPDs, tested with 10\/350 \u00b5s waveform. Values start at 12.5 kA, with 25 kA recommended in high-risk areas.<\/p>\r\n<\/li>\r\n \t<li data-start=\"3760\" data-end=\"3881\">\r\n<p data-start=\"3762\" data-end=\"3881\"><strong data-start=\"3762\" data-end=\"3779\">Response Time<\/strong>: SPDs act in nanoseconds. The faster the reaction, the better protection for sensitive electronics.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"3883\" data-end=\"4010\">These parameters should always be matched with the system\u2019s exposure level, earthing type, and equipment insulation category.<\/p>\r\n\r\n<h2 data-start=\"4017\" data-end=\"4064\">System Earthing and Wiring Configurations<\/h2>\r\n<p data-start=\"4065\" data-end=\"4202\">Earthing type is often overlooked, but it is one of the most decisive factors when choosing a Single-Phase Surge Protection Device.<\/p>\r\n\r\n<ul data-start=\"4204\" data-end=\"4774\">\r\n \t<li data-start=\"4204\" data-end=\"4497\">\r\n<p data-start=\"4206\" data-end=\"4497\"><strong data-start=\"4206\" data-end=\"4220\">TT Systems<\/strong>: Require 1P+N (also called 1+1) SPD. This configuration uses MOV protection between line and neutral, plus a spark gap or dedicated element between neutral and PE. It ensures controlled discharge to earth, which is vital in TT where neutral potential can rise during faults.<\/p>\r\n<\/li>\r\n \t<li data-start=\"4498\" data-end=\"4670\">\r\n<p data-start=\"4500\" data-end=\"4670\"><strong data-start=\"4500\" data-end=\"4526\">TN-S or TN-C-S Systems<\/strong>: Can use either 1P or 1P+N depending on the design of the distribution board. Both line-to-neutral and line-to-earth paths must be protected.<\/p>\r\n<\/li>\r\n \t<li data-start=\"4671\" data-end=\"4774\">\r\n<p data-start=\"4673\" data-end=\"4774\"><strong data-start=\"4673\" data-end=\"4689\">TN-C Systems<\/strong>: Usually apply 1P or 2P SPDs depending on whether the PEN conductor is accessible.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"4776\" data-end=\"5017\">For all systems, wiring rules remain the same: keep the SPD\u2019s connection to earth as short as possible, ideally less than 0.5 m. Long leads increase inductance and therefore increase the residual voltage that the protected device will see.<\/p>\r\n\r\n<h2 data-start=\"5024\" data-end=\"5058\">Step-by-Step Selection Guide<\/h2>\r\n<p data-start=\"5060\" data-end=\"5255\">This is the heart of the decision-making process. Many engineers and buyers search specifically for how to choose a single phase SPD, so this section provides a detailed, practical roadmap:<\/p>\r\n\r\n<h3 data-start=\"5257\" data-end=\"5559\"><strong data-start=\"5257\" data-end=\"5295\">Step 1: Evaluate Risk and Exposure<\/strong><\/h3>\r\n<p data-start=\"5257\" data-end=\"5559\">Determine whether the building has an external lightning protection system (LPS) or is supplied by overhead lines. If yes, a Type 1 SPD at the service entrance is mandatory. For underground supplies in low-risk areas, a high-capacity Type 2 may be sufficient.<\/p>\r\n\r\n<h3 data-start=\"5561\" data-end=\"5803\"><strong data-start=\"5561\" data-end=\"5601\">Step 2: Identify the Earthing System<\/strong><\/h3>\r\n<p data-start=\"5561\" data-end=\"5803\">Check whether your installation is TT, TN-S, TN-C-S, or TN-C. This determines if you need a 1P SPD, a 1P+N SPD, or a 2P SPD. Selecting the wrong wiring configuration can render the SPD ineffective.<\/p>\r\n\r\n<h3 data-start=\"5805\" data-end=\"5846\"><strong data-start=\"5805\" data-end=\"5844\">Step 3: Define the Protection Stage<\/strong><\/h3>\r\n<ul data-start=\"5847\" data-end=\"6077\">\r\n \t<li data-start=\"5847\" data-end=\"5908\">\r\n<p data-start=\"5849\" data-end=\"5908\">At the service entrance: Type 1 or Type 1+2 combined SPD.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5909\" data-end=\"5978\">\r\n<p data-start=\"5911\" data-end=\"5978\">At distribution panels: Type 2, with In \u2265 20 kA and Imax \u2265 40 kA.<\/p>\r\n<\/li>\r\n \t<li data-start=\"5979\" data-end=\"6077\">\r\n<p data-start=\"5981\" data-end=\"6077\">At sensitive loads: Type 3, to reduce Up below the insulation withstand of electronic devices.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h3 data-start=\"6079\" data-end=\"6159\"><strong data-start=\"6079\" data-end=\"6115\">Step 4: Select Technical Ratings<\/strong><\/h3>\r\n<p data-start=\"6079\" data-end=\"6159\">Match the SPD\u2019s ratings to your system:<\/p>\r\n\r\n<ul data-start=\"6160\" data-end=\"6369\">\r\n \t<li data-start=\"6160\" data-end=\"6197\">\r\n<p data-start=\"6162\" data-end=\"6197\">Uc: 275V AC for 230\/240V systems.<\/p>\r\n<\/li>\r\n \t<li data-start=\"6198\" data-end=\"6304\">\r\n<p data-start=\"6200\" data-end=\"6304\">Up: Must be lower than the equipment insulation category (IEC 60664: Cat II \u2248 2.5 kV, Cat III \u2248 4 kV).<\/p>\r\n<\/li>\r\n \t<li data-start=\"6305\" data-end=\"6369\">\r\n<p data-start=\"6307\" data-end=\"6369\">In\/Imax\/Iimp: According to installation level and risk zone.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h3 data-start=\"6371\" data-end=\"6689\"><strong data-start=\"6371\" data-end=\"6415\">Step 5: Plan Coordination Between Stages<\/strong><\/h3>\r\n<p data-start=\"6371\" data-end=\"6689\">SPDs must work together. The upstream device must absorb energy without passing destructive voltage downstream, while the downstream SPD fine-tunes protection. Maintain at least 10 meters between devices, or insert decoupling inductance to ensure proper energy sharing.<\/p>\r\n\r\n<h3 data-start=\"6691\" data-end=\"6928\"><strong data-start=\"6691\" data-end=\"6739\">Step 6: Ensure Proper Overcurrent Protection<\/strong><\/h3>\r\n<p data-start=\"6691\" data-end=\"6928\">Every SPD requires backup protection. Unless the SPD includes an integrated fuse, install an MCB or fuse in series. This prevents short-circuit events when the SPD reaches end of life.<\/p>\r\n\r\n<h3 data-start=\"6930\" data-end=\"7027\"><strong data-start=\"6930\" data-end=\"6979\">Step 7: Consider Service Life and Maintenance<\/strong><\/h3>\r\n<p data-start=\"6930\" data-end=\"7027\">SPDs degrade over time. Choose models with:<\/p>\r\n\r\n<ul data-start=\"7028\" data-end=\"7241\">\r\n \t<li data-start=\"7028\" data-end=\"7093\">\r\n<p data-start=\"7030\" data-end=\"7093\">Status indication windows that show green\/red conditions.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7094\" data-end=\"7162\">\r\n<p data-start=\"7096\" data-end=\"7162\">Remote signaling contacts for monitoring in control systems.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7163\" data-end=\"7241\">\r\n<p data-start=\"7165\" data-end=\"7241\">Replaceable plug-in modules, so maintenance does not require rewiring.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"7243\" data-end=\"7418\">Following this step-by-step process ensures that your single phase SPD is not only correctly rated but also correctly installed and maintained for long-term reliability.<\/p>\r\n\r\n<h2 data-start=\"7425\" data-end=\"7476\">Practical Installation Tips and Common Errors<\/h2>\r\n<p data-start=\"7478\" data-end=\"7602\">Even the best single phase protection devices will fail if installed incorrectly. Follow these engineering principles:<\/p>\r\n\r\n<ul data-start=\"7604\" data-end=\"7913\">\r\n \t<li data-start=\"7604\" data-end=\"7653\">\r\n<p data-start=\"7606\" data-end=\"7653\">Keep leads short and direct, less than 0.5 m.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7654\" data-end=\"7716\">\r\n<p data-start=\"7656\" data-end=\"7716\">Separate power and signal cables to avoid coupling surges.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7717\" data-end=\"7769\">\r\n<p data-start=\"7719\" data-end=\"7769\">Do not bundle SPD leads with protected circuits.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7770\" data-end=\"7844\">\r\n<p data-start=\"7772\" data-end=\"7844\">Always connect the SPD earth to the closest equipotential bonding bar.<\/p>\r\n<\/li>\r\n \t<li data-start=\"7845\" data-end=\"7913\">\r\n<p data-start=\"7847\" data-end=\"7913\">Respect the coordination distances between different SPD stages.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"7915\" data-end=\"8130\">Common mistakes include installing only one stage, forgetting N-PE protection in TT systems, or oversizing SPDs without actual need. Each of these reduces protection efficiency and increases costs without benefit.<\/p>\r\n\r\n<h2 data-start=\"8137\" data-end=\"8163\">Example Applications<\/h2>\r\n<ul data-start=\"8165\" data-end=\"8850\">\r\n \t<li data-start=\"8165\" data-end=\"8343\">\r\n<p data-start=\"8167\" data-end=\"8343\"><strong data-start=\"8167\" data-end=\"8195\">Residential Applications<\/strong>: A Type 2 SPD (In 20 kA, Imax 40 kA, Up &lt; 1.5 kV) installed in the main distribution board protects household electronics from grid disturbances.<\/p>\r\n<\/li>\r\n \t<li data-start=\"8344\" data-end=\"8498\">\r\n<p data-start=\"8346\" data-end=\"8498\"><strong data-start=\"8346\" data-end=\"8370\">Commercial Buildings<\/strong>: A Type 1+2 SPD at the main switchboard combined with Type 2 SPDs at floor distribution panels ensures continuity of service.<\/p>\r\n<\/li>\r\n \t<li data-start=\"8499\" data-end=\"8673\">\r\n<p data-start=\"8501\" data-end=\"8673\"><strong data-start=\"8501\" data-end=\"8526\">Industrial Facilities<\/strong>: Type 1 SPDs rated at 25 kA Iimp at the service entrance, with coordinated Type 2 SPDs in motor control centers and Type 3 SPDs protecting PLCs.<\/p>\r\n<\/li>\r\n \t<li data-start=\"8674\" data-end=\"8850\">\r\n<p data-start=\"8676\" data-end=\"8850\"><strong data-start=\"8676\" data-end=\"8696\">Solar PV Systems<\/strong>: On the DC side, use PV-rated SPDs. On the AC side, a Type 2 single-phase SPD at the inverter output protects both the inverter and the grid interface.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<h2 data-start=\"8857\" data-end=\"8873\">Conclusion<\/h2>\r\n<p data-start=\"8875\" data-end=\"9090\">Choosing the right Single-Phase Surge Protection Device requires more than scanning a datasheet. It means understanding your system, evaluating risks, applying IEC standards, and matching parameters carefully.<\/p>\r\n\r\n<ul data-start=\"9092\" data-end=\"9348\">\r\n \t<li data-start=\"9092\" data-end=\"9151\">\r\n<p data-start=\"9094\" data-end=\"9151\">At the entrance, protect against lightning with Type 1.<\/p>\r\n<\/li>\r\n \t<li data-start=\"9152\" data-end=\"9203\">\r\n<p data-start=\"9154\" data-end=\"9203\">In distribution, rely on robust Type 2 devices.<\/p>\r\n<\/li>\r\n \t<li data-start=\"9204\" data-end=\"9266\">\r\n<p data-start=\"9206\" data-end=\"9266\">For sensitive electronics, add Type 3 at the point of use.<\/p>\r\n<\/li>\r\n \t<li data-start=\"9267\" data-end=\"9348\">\r\n<p data-start=\"9269\" data-end=\"9348\">Always respect your earthing system, wiring practices, and maintenance needs.<\/p>\r\n<\/li>\r\n<\/ul>\r\n<p data-start=\"9350\" data-end=\"9539\">By applying these principles, electrical engineers and procurement professionals can ensure that their systems are not only compliant but also resilient, cost-effective, and future-ready.<\/p>"},"_links":{"self":[{"href":"https:\/\/www.britecelectric.com\/pt\/wp-json\/wp\/v2\/blog\/2176","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.britecelectric.com\/pt\/wp-json\/wp\/v2\/blog"}],"about":[{"href":"https:\/\/www.britecelectric.com\/pt\/wp-json\/wp\/v2\/types\/blog"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.britecelectric.com\/pt\/wp-json\/wp\/v2\/media\/2175"}],"wp:attachment":[{"href":"https:\/\/www.britecelectric.com\/pt\/wp-json\/wp\/v2\/media?parent=2176"}],"wp:term":[{"taxonomy":"blog_category","embeddable":true,"href":"https:\/\/www.britecelectric.com\/pt\/wp-json\/wp\/v2\/blog_category?post=2176"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}