{"id":797,"date":"2023-12-19T16:31:05","date_gmt":"2023-12-19T08:31:05","guid":{"rendered":"https:\/\/www.britecelectric.com\/?post_type=blog&p=797"},"modified":"2024-09-05T16:36:33","modified_gmt":"2024-09-05T08:36:33","slug":"surge-protector-faq","status":"publish","type":"blog","link":"https:\/\/www.britecelectric.com\/pt\/blog\/surge-protector-faq\/","title":{"rendered":"Perguntas frequentes sobre protetor contra surtos"},"content":{"rendered":"Os protetores contra surtos duram para sempre?<\/strong>\r\n\r\nN\u00e3o, eles n\u00e3o querem. Cada vez que um filtro de linha redireciona uma oscila\u00e7\u00e3o de energia para longe do equipamento conectado, a estrutura interna do protetor sofre alguns danos. Com o tempo, as pe\u00e7as do filtro de linha que mant\u00eam o equipamento conectado seguro simplesmente param de funcionar. Quanto tempo isso leva depende da frequ\u00eancia e da intensidade dos picos de energia.\r\n\r\nAs prote\u00e7\u00f5es existentes como MCB, ELCB etc. n\u00e3o s\u00e3o suficientes para proteger contra surtos?<\/strong>\r\n\r\nAll the existing protecting devices like MCB, ELCB etc. are current sensitive devices. They get activated based on a fault current. These devices are triggered when the fault current persists for duration of more than 3 to 20 milliseconds. However, the surge typically lasts for a few micro seconds only during which time it causes all the damage.\r\n\r\nHence the conventional devices like MCB, ELCB fuses etc. are not effective in protection against surges. In view of the above, special equipment called surge protection device which has a response time of two nanoseconds is required to be installed to protect against the surges.\r\n\r\nO que \u00e9 uma oscila\u00e7\u00e3o de energia?<\/strong>\r\n\r\nUma oscila\u00e7\u00e3o de energia \u00e9 um pico na corrente el\u00e9trica que flui pelos fios de sua casa. Eles podem danificar aparelhos comuns, eletr\u00f4nicos AV sens\u00edveis e equipamentos de inform\u00e1tica.\r\n\r\nQuais s\u00e3o as diferentes tecnologias utilizadas nos SPDs?<\/strong>\r\n\r\nAlgumas das tecnologias populares usadas em SPDs s\u00e3o as seguintes:\r\n
    \r\n \t
  1. i) Tubos de descarga de g\u00e1s<\/li>\r\n \t
  2. ii) Varistores de \u00f3xido met\u00e1lico<\/li>\r\n<\/ol>\r\niii) Centelha\r\n
      \r\n \t
    1. iv) diodo Zener<\/li>\r\n \t
    2. v) Diodos Avalanche de Sil\u00edcio<\/li>\r\n<\/ol>\r\nEntre estes, tubos de descarga de g\u00e1s, varistores de \u00f3xido met\u00e1lico e centelhadores s\u00e3o os tipos mais populares de p\u00e1ra-raios.\r\n\r\nO que causa uma oscila\u00e7\u00e3o de energia?<\/strong>\r\n\r\nA maioria dos picos de energia ocorre dentro de sua casa. Os picos de energia s\u00e3o causados \u200b\u200bpor muitos fatores diferentes, incluindo condi\u00e7\u00f5es clim\u00e1ticas adversas, fia\u00e7\u00e3o el\u00e9trica defeituosa ou danificada ou o ligar e desligar repentino de um dispositivo el\u00e9trico de alta pot\u00eancia, como um ar condicionado ou um grande motor el\u00e9trico.\r\n\r\nAs classifica\u00e7\u00f5es dos SPDs devem ser selecionadas dependendo da corrente da linha?<\/strong>\r\n\r\nGeralmente, os SPDs instalados no circuito de pot\u00eancia el\u00e9trica s\u00e3o conectados em paralelo e, portanto, ser\u00e3o independentes da corrente de carga (linha).\r\n\r\nPor que se preocupar com picos de energia?<\/strong>\r\n\r\nFortes picos de energia podem destruir o equipamento dom\u00e9stico em um instante. Al\u00e9m dos surtos causados \u200b\u200bpor tempestades, uma casa comum pode sofrer v\u00e1rios surtos \u201cocultos\u201d por dia, provenientes de outras fontes diversas. Esses surtos menores causam danos cumulativos aos componentes eletr\u00f4nicos, encurtando sua vida \u00fatil e eventualmente causando falhas.\r\n\r\nComo determinar quais tipos de SPDs ser\u00e3o instalados em um determinado local?<\/strong>\r\n\r\nA sele\u00e7\u00e3o de SPDs em um determinado local depende de:\r\n
        \r\n \t
      1. a) A topografia do local em termos de queda de raios.<\/li>\r\n \t
      2. b) Suscetibilidade a surtos de comuta\u00e7\u00e3o em termos de proximidade de grandes cargas\/conectados a alimentadores rurais etc.<\/li>\r\n \t
      3. c) Sensibilidade do equipamento conectado ao circuito.<\/li>\r\n<\/ol>\r\nNormally SPDs with Class-B & C are installed at the main panels and SPDs with Class-C rate are installed at the sub panels. The ratings for class-B, SPDs shall be a minimum of 12.5 KA Iimp.\r\n\r\nFor the Class-C (Imax. rating), it should be, a minimum of 40 kA at the sub panels.\r\n\r\nFor the Class-D SPDs which are installed near sensitive equipment, the criteria shall be the residual voltage or the protection level which should be lower than the temporary over voltage withstanding capacity of the protected equipment.\r\n\r\nO que um protetor contra surtos faz?<\/strong>\r\n\r\nUm protetor contra surtos protege os componentes eletr\u00f4nicos dos efeitos nocivos de picos de energia e picos de tens\u00e3o. Os protetores contra surtos podem absorver e dissipar a energia de um surto, de modo que o equipamento conectado fique protegido contra surtos.\r\n\r\nComo saber se o SPD instalado est\u00e1 funcionando?<\/strong>\r\n\r\nComo os SPDs est\u00e3o sempre conectados em paralelo ao circuito el\u00e9trico, durante o funcionamento normal n\u00e3o \u00e9 poss\u00edvel saber se est\u00e3o em condi\u00e7\u00f5es de funcionamento ou n\u00e3o. Portanto \u00e9 necess\u00e1ria uma indica\u00e7\u00e3o local e remota atrav\u00e9s de contato el\u00e9trico para conhecer e monitorar a salubridade do SPD.\r\n\r\n\u00c9 necess\u00e1rio ter aterramento separado para SPDs?<\/strong>\r\n\r\nN\u00e3o \u00e9 necess\u00e1rio ter um aterramento separado ou dedicado para os SPDs. Os SPDs devem estar sempre conectados \u00e0 rede geral de aterramento.\r\n\r\n\u00c9 necess\u00e1rio um bom sistema de aterramento para o funcionamento eficiente do SPD?<\/strong>\r\n\r\nTodos os SPDs funcionam desviando o excesso de energia para o solo. Portanto, \u00e9 imperativo que o sistema de aterramento conectado ao SPD esteja em condi\u00e7\u00f5es de funcionamento eficientes para que a corrente de surto possa fluir para a terra sem qualquer obst\u00e1culo.\r\n\r\nOs SPDs est\u00e3o dispon\u00edveis para outras aplica\u00e7\u00f5es al\u00e9m do circuito el\u00e9trico, como linhas telef\u00f4nicas, linhas de dados, etc.?<\/strong>\r\n\r\nOs SPDs certamente est\u00e3o dispon\u00edveis para todos os circuitos, como linhas telef\u00f4nicas, linhas de dados, linhas Ethernet, linhas de sinal, etc. Em todos esses circuitos, os SPDs s\u00e3o conectados em s\u00e9rie.\r\n\r\nOs SPDs prim\u00e1rios por si s\u00f3 s\u00e3o suficientes para a prote\u00e7\u00e3o do equipamento?<\/strong>\r\n\r\nN\u00e3o, desde uma instala\u00e7\u00e3o pequena at\u00e9 uma instala\u00e7\u00e3o grande, normalmente \u00e9 necess\u00e1rio adotar uma abordagem em cascata ou em camadas onde a prote\u00e7\u00e3o prim\u00e1ria \u00e9 instalada na botoneira de servi\u00e7o e a prote\u00e7\u00e3o secund\u00e1ria nas centrais de deriva\u00e7\u00e3o. Cada instala\u00e7\u00e3o requer an\u00e1lise individual para determinar a prote\u00e7\u00e3o correta para atender \u00e0s necessidades do equipamento utilizado. Pode at\u00e9 ser necess\u00e1rio incluir SPDs adicionais no ponto de uso se este equipamento estiver localizado a alguma dist\u00e2ncia do painel de alimenta\u00e7\u00e3o. Uma abordagem em cascata\u00e9 recomendado pelo IEEE e esse tipo de abordagem fornecer\u00e1 a prote\u00e7\u00e3o mais eficaz contra surtos em toda a instala\u00e7\u00e3o. Para obter mais informa\u00e7\u00f5es sobre onde aplicar os SPDs, selecione o tipo de ambiente de seu interesse: industrial, comercial ou residencial.\r\n\r\nPor que preciso de um SPD quando j\u00e1 possuo um transformador de isolamento?<\/strong>\r\n\r\nOs transformadores de isolamento fornecem uma rejei\u00e7\u00e3o de modo comum muito boa, mas n\u00e3o fornecem uma boa rejei\u00e7\u00e3o de modo diferencial (normal). Em outras palavras, um surto sobreposto igualmente nos condutores de linha (L) e neutro (N) ser\u00e1 rejeitado pelo transformador de isolamento, enquanto um surto que aparece diferencialmente entre os condutores L e N passar\u00e1 pelo transformador. Al\u00e9m disso, tenha em mente que a maioria dos transientes s\u00e3o gerados pelas cargas dentro da instala\u00e7\u00e3o, no lado da carga destastransformadores. Para minimizar os efeitos desses transientes gerados internamente de um equipamento para outro, um SPD deve ser colocado.","protected":false},"featured_media":798,"parent":0,"menu_order":176,"template":"","meta":{"_acf_changed":false},"blog_category":[8],"class_list":["post-797","blog","type-blog","status-publish","has-post-thumbnail","hentry","blog_category-company-news"],"acf":{"des":"Do surge protectors last forever?No, they do not. Each time a surge protector reroutes a power surge away from your connected equipment, the internal structure of the protector takes a little bit of damage.","txt":"Do surge protectors last forever?<\/strong>\r\n\r\nNo, they do not. Each time a surge protector reroutes a power surge away from your connected equipment, the internal structure of the protector takes a little bit of damage. Over time the parts of the surge protector that keep your connected equipment safe simply stop working. How long this takes depends on the frequency and strength of power surges.\r\n\r\nAre the existing protections like MCB, ELCB etc. not sufficient to protect against surges?<\/strong>\r\n\r\nAll the existing protecting devices like MCB, ELCB etc. are current sensitive devices. They get activated based on a fault current. These devices are triggered when the fault current persists for duration of more than 3 to 20 milliseconds. However, the surge typically lasts for a few micro seconds only during which time it causes all the damage.\r\n\r\nHence the conventional devices like MCB, ELCB fuses etc. are not effective in protection against surges. In view of the above, special equipment called surge protection device which has a response time of two nanoseconds is required to be installed to protect against the surges.\r\n\r\nWhat is a power surge?<\/strong>\r\n\r\nA power surge is a spike in the electrical current flowing through the wires of your house. They can damage common appliances, sensitive AV electronics and computer equipment.\r\n\r\nWhat are the different technologies used in SPDs?<\/strong>\r\n\r\nSome of the popular technologies used in SPDs are the following:\r\n
          \r\n \t
        1. i) Gas discharge tubes<\/li>\r\n \t
        2. ii) Metal oxide varistors<\/li>\r\n<\/ol>\r\niii) Spark gap\r\n
            \r\n \t
          1. iv) Zener diode<\/li>\r\n \t
          2. v) Silicon Avalanche diodes<\/li>\r\n<\/ol>\r\nAmong these, gas discharge tubes, metal oxide varistors and spark gap are the most popular types of surge arresters.\r\n\r\nWhat causes a power surge?<\/strong>\r\n\r\nMost power surges stem from inside your home. Power surges are caused by many different factors, including severe weather, faulty or damaged electric wiring or the sudden turning on and off of a high power electrical device like an air conditioner or large electric motor.\r\n\r\nAre the SPDs ratings to be selected depending on the line current?<\/strong>\r\n\r\nGenerally, the SPDs installed on the electrical Power circuit are connected in parallel and hence will be independent of load (line) current.\r\n\r\nWhy worry about power surges?<\/strong>\r\n\r\nStrong power surges can wipe out your home equipment in an instant. In addition to surges caused by storms, the average home can experience multiple \u201chidden\u201d surges a day from other various sources. These smaller surges cause cumulative damage to electronics, shortening their life and eventually causing them to fail.\r\n\r\nHow to determine what types of SPDs are to be installed at a given location?<\/strong>\r\n\r\nThe selection of SPDs at a given location depends on:\r\n
              \r\n \t
            1. a) The topography of the location in terms of lightning strikes.<\/li>\r\n \t
            2. b) Susceptibility to switching surges in terms of proximity to large loads \/ connected to rural feeder etc.<\/li>\r\n \t
            3. c) Sensitivity of the equipment connected to the circuit.<\/li>\r\n<\/ol>\r\nNormally SPDs with Class-B & C are installed at the main panels and SPDs with Class-C rate are installed at the sub panels. The ratings for class-B, SPDs shall be a minimum of 12.5 KA Iimp.\r\n\r\nFor the Class-C (Imax. rating), it should be, a minimum of 40 kA at the sub panels.\r\n\r\nFor the Class-D SPDs which are installed near sensitive equipment, the criteria shall be the residual voltage or the protection level which should be lower than the temporary over voltage withstanding capacity of the protected equipment.\r\n\r\nWhat does a surge protector do?<\/strong>\r\n\r\nA surge protector safeguards electronics from the harmful effects of power surges and voltage spikes. Surge protectors can absorb and dissipate the power of a surge so that connected equipment is shielded from the surge.\r\n\r\nHow does one know the SPD installed is working?<\/strong>\r\n\r\nSince the SPDs are always connected in parallel to the electrical circuit, during the normal course it is not possible to know whether they are in working condition or not. Hence it is necessary to have a local and remote indication using electrical contact in order to know and monitor the healthiness of the SPD.\r\n\r\nIs it necessary for having separate grounding for SPDs?<\/strong>\r\n\r\nIt is not necessary to have a separate or dedicated grounding for SPDs. The SPDs should always be connected to the general earth grid.\r\n\r\nIs a good earthing system necessary for efficient working of the SPD?<\/strong>\r\n\r\nAll SPDs work by diverting the excess energy to the ground. Hence it is imperative that the earthing system connected to the SPD must be in efficient working condition so that the surge current can flow to the earth without any hindrance.\r\n\r\nAre SPDs available for applications other than the electrical circuit like telephone lines, data lines etc.?<\/strong>\r\n\r\nSPDs are certainly available for every circuit like telephone lines, data lines, Ethernet lines, signal lines etc. In all these circuits SPDs are connected in series.\r\n\r\nAre primary SPDs alone sufficient for equipment protection?<\/strong>\r\n\r\nNo, from a small facility to a large facility, it is usually necessary to adopt a cascaded or layered approach where primary protection is installed at the service entrance panel, and secondary protection at branch panels. Each facility requires individual analysis to determine the right protection to meet the needs of the equipment being used. It can even be necessary to include additional point-of-use SPDs if this equipment is located some distance from the supplying panel. A cascaded approach is recommended by the IEEE and this type of approach will provide the most effective surge protection throughout a facility. For more information on where to apply SPDs, select the type of environment you\u2019re interested in: industrial, commercial, or residential.\r\n\r\nWhy do I need an SPD when I already have an isolation transformer?<\/strong>\r\n\r\nIsolation transformers provide very good common mode rejection but do not provide good differential (normal) mode rejection. In other words, a surge superimposed equally on both the line (L) and neutral (N) conductors will see rejection by the isolation transformer, while a surge appearing differentially between the L and N conductors will pass through the transformer. Also, keep in mind the majority of transients are being generated by the loads within the facility, on the load side of these transformers. To minimize the effects of these internally generated transients from one piece of equipment to another an SPD should be placed."},"_links":{"self":[{"href":"https:\/\/www.britecelectric.com\/pt\/wp-json\/wp\/v2\/blog\/797","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\/798"}],"wp:attachment":[{"href":"https:\/\/www.britecelectric.com\/pt\/wp-json\/wp\/v2\/media?parent=797"}],"wp:term":[{"taxonomy":"blog_category","embeddable":true,"href":"https:\/\/www.britecelectric.com\/pt\/wp-json\/wp\/v2\/blog_category?post=797"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}