![\"DC](\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/02\/d99df32fb440fa476637e43c0bd1b7297a08317ffd7402d63b776f446614f1d9-1024x266.jpg\")
<\/figure>\n\n\n\nKey ratings to check on the datasheet<\/h2>\n\n\n\n\n- UCPV<\/sub> \/ Uc<\/sub>:<\/strong> maximum continuous operating voltage. On a PV array, compare it with the calculated maximum string open-circuit voltage, including the cold-temperature increase. Do not select from nominal operating voltage alone.<\/li>\n\n\n
- Up<\/sub>:<\/strong> voltage protection level at the stated test condition. Compare it with the equipment impulse withstand and allow for installation lead voltage drop. Lower is not automatically better if the continuous voltage rating is unsuitable.<\/li>\n\n\n
- In<\/sub> and Im\u00e1ximo<\/sub>:<\/strong> discharge ratings under the specified 8\/20 \u03bcs test waveform. Compare products only when the waveform, test class and rating basis are the same.<\/li>\n\n\n
- Iimp<\/sub>:<\/strong> impulse current rating for a Type 1\/Class I device, stated with its test waveform. It is not interchangeable with Im\u00e1ximo<\/sub>.<\/li>\n\n\n
- Short-circuit and disconnector information:<\/strong> check the manufacturer\u2019s PV fault-current rating, required backup protection, connection scheme, status indicator and replacement instructions.<\/li>\n<\/ul>\n\n\n\n
PV standards and the scope of this guide<\/h2>\n\n\n\n
IEC 61643-31<\/a> specifies test requirements for SPDs on the DC side of PV generators and inverters with rated voltages up to 1,500 V DC. Its scope excludes PV systems that include energy storage. IEC 61643-32<\/a> provides application guidance for PV SPD selection, installation and coordination. For a battery or another low-voltage DC application, check the applicable product standard and the exact device certification; a PV-only declaration is not proof of suitability for that circuit.<\/p>\n\n\n\nType 1 or Type 2: how to decide<\/h2>\n\n\n\n
Type 1\/Class I devices are tested for lightning-current impulses; Type 2\/Class II devices are tested for induced and switching surges. The required class and placement depend on the building lightning protection system, separation distance, local installation rules and the project risk assessment. A rooftop array does not automatically require Type 1, and an open-field array does not automatically make one specific device or position correct. Use the project lightning-protection design and the manufacturer\u2019s coordination instructions.<\/p>\n\n\n\n
Where to install protection in a PV system<\/h2>\n\n\n\n
Review the array or combiner-box side, the inverter DC input and the AC side of the inverter as separate protection points. The number and position of SPDs depend on cable lengths, earthing arrangement and equipment withstand ratings. Keep SPD connections short and route conductors according to the installation instructions; long leads can increase the voltage reaching equipment. See our guia de prote\u00e7\u00e3o de inversores solares<\/a> e PV protection overview<\/a> for the wider design context.<\/p>\n\n\n\nCan an AC SPD be used on a DC circuit?<\/h2>\n\n\n\n
Do not assume that an AC-only SPD is suitable for a PV DC string. The continuous voltage, disconnection behavior, available fault current and certification must all match the DC application. Read our AC SPD on DC systems<\/a> article for the failure modes and selection checks.<\/p>\n\n\n\nA practical PV SPD selection checklist<\/h2>\n\n\n\n\n- Calculate maximum PV string open-circuit voltage at the site\u2019s lowest design temperature.<\/li>\n\n\n
- Confirm the SPD is intended and certified for the PV DC application and that UCPV<\/sub> covers the calculated voltage.<\/li>\n\n\n
- Choose the test class and discharge ratings from the lightning protection design and local installation rules.<\/li>\n\n\n
- Compare Up<\/sub> with the protected equipment\u2019s withstand rating and account for the installed wiring.<\/li>\n\n\n
- Check earthing arrangement, polarity and the manufacturer\u2019s connection diagram.<\/li>\n\n\n
- Confirm backup protection, fault-current limits, disconnector\/status indication and environmental enclosure ratings.<\/li>\n\n\n
- Coordinate devices at multiple protection points using the manufacturer\u2019s instructions; do not infer coordination from kA numbers alone.<\/li>\n<\/ul>\n\n\n\n
What about batteries, EV chargers and telecom DC?<\/h2>\n\n\n\n
These systems have different voltage ranges, source behavior and fault-current conditions. Do not transfer a PV SPD specification automatically to a battery rack or EV charging DC bus. Obtain the device\u2019s declared application and test standard, check maximum continuous voltage and fault current, and follow the system integrator\u2019s protection design. For context, see our EV charging and energy storage article<\/a>.<\/p>\n\n\n\nPrice and procurement<\/h2>\n\n\n\n
A reliable price comparison needs the same application, voltage rating, test class, discharge ratings, pole configuration, enclosure and certification documents. Generic online price bands do not establish that a device is suitable for a particular installation. Ask the supplier for the model-specific datasheet, declaration or test report, wiring diagram, backup-protection requirements and quotation.<\/p>\n\n\n\n
Perguntas frequentes<\/h2>\n\n\n\nIs a 1,100 V DC SPD suitable for a 1,000 V PV system?<\/h3>\n\n\n\n
The nominal system label alone is insufficient. Calculate the array\u2019s maximum open-circuit voltage at the lowest design temperature and compare it with the SPD\u2019s stated UCPV<\/sub>. Also verify the connection scheme, fault-current conditions and manufacturer instructions. There is no universal 1.2\u00d7 multiplier that can replace this calculation.<\/p>\n\n\n\nUma classifica\u00e7\u00e3o de kA maior significa sempre uma prote\u00e7\u00e3o melhor?<\/h3>\n\n\n\n
No. Compare the same test waveform and class, then consider voltage protection level, continuous voltage rating, installation location and coordination. A larger single rating cannot compensate for an unsuitable voltage rating or incorrect wiring.<\/p>\n\n\n\n
Conclus\u00e3o<\/h2>\n\n\n\n
The safest way to choose a DC SPD is to start with the actual circuit and the equipment to be protected, then verify the device\u2019s ratings, application scope and installation instructions. For PV projects, use IEC 61643-31 product documentation and IEC 61643-32 application guidance alongside local rules. Explore Kuangya DC SPD products<\/a> and request model-specific technical documents before specifying a device.<\/p>","protected":false},"excerpt":{"rendered":"A DC surge protective device (SPD) limits transient overvoltage and diverts surge current away from equipment. For solar PV, the key questions are where the device is installed, whether it is rated for the maximum PV open-circuit voltage at the lowest expected temperature, and how it coordinates with the inverter and other protective devices. This […]<\/p>\n","protected":false},"author":4,"featured_media":2529,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[42],"tags":[],"class_list":["post-2528","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-surge-protection-lightning-safety"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/posts\/2528","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/comments?post=2528"}],"version-history":[{"count":3,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/posts\/2528\/revisions"}],"predecessor-version":[{"id":4915,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/posts\/2528\/revisions\/4915"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/media\/2529"}],"wp:attachment":[{"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/media?parent=2528"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/categories?post=2528"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/tags?post=2528"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
PV standards and the scope of this guide<\/h2>\n\n\n\n
IEC 61643-31<\/a> specifies test requirements for SPDs on the DC side of PV generators and inverters with rated voltages up to 1,500 V DC. Its scope excludes PV systems that include energy storage. IEC 61643-32<\/a> provides application guidance for PV SPD selection, installation and coordination. For a battery or another low-voltage DC application, check the applicable product standard and the exact device certification; a PV-only declaration is not proof of suitability for that circuit.<\/p>\n\n\n\n Type 1\/Class I devices are tested for lightning-current impulses; Type 2\/Class II devices are tested for induced and switching surges. The required class and placement depend on the building lightning protection system, separation distance, local installation rules and the project risk assessment. A rooftop array does not automatically require Type 1, and an open-field array does not automatically make one specific device or position correct. Use the project lightning-protection design and the manufacturer\u2019s coordination instructions.<\/p>\n\n\n\n Review the array or combiner-box side, the inverter DC input and the AC side of the inverter as separate protection points. The number and position of SPDs depend on cable lengths, earthing arrangement and equipment withstand ratings. Keep SPD connections short and route conductors according to the installation instructions; long leads can increase the voltage reaching equipment. See our guia de prote\u00e7\u00e3o de inversores solares<\/a> e PV protection overview<\/a> for the wider design context.<\/p>\n\n\n\n Do not assume that an AC-only SPD is suitable for a PV DC string. The continuous voltage, disconnection behavior, available fault current and certification must all match the DC application. Read our AC SPD on DC systems<\/a> article for the failure modes and selection checks.<\/p>\n\n\n\n These systems have different voltage ranges, source behavior and fault-current conditions. Do not transfer a PV SPD specification automatically to a battery rack or EV charging DC bus. Obtain the device\u2019s declared application and test standard, check maximum continuous voltage and fault current, and follow the system integrator\u2019s protection design. For context, see our EV charging and energy storage article<\/a>.<\/p>\n\n\n\n A reliable price comparison needs the same application, voltage rating, test class, discharge ratings, pole configuration, enclosure and certification documents. Generic online price bands do not establish that a device is suitable for a particular installation. Ask the supplier for the model-specific datasheet, declaration or test report, wiring diagram, backup-protection requirements and quotation.<\/p>\n\n\n\n The nominal system label alone is insufficient. Calculate the array\u2019s maximum open-circuit voltage at the lowest design temperature and compare it with the SPD\u2019s stated UCPV<\/sub>. Also verify the connection scheme, fault-current conditions and manufacturer instructions. There is no universal 1.2\u00d7 multiplier that can replace this calculation.<\/p>\n\n\n\n No. Compare the same test waveform and class, then consider voltage protection level, continuous voltage rating, installation location and coordination. A larger single rating cannot compensate for an unsuitable voltage rating or incorrect wiring.<\/p>\n\n\n\n The safest way to choose a DC SPD is to start with the actual circuit and the equipment to be protected, then verify the device\u2019s ratings, application scope and installation instructions. For PV projects, use IEC 61643-31 product documentation and IEC 61643-32 application guidance alongside local rules. Explore Kuangya DC SPD products<\/a> and request model-specific technical documents before specifying a device.<\/p>","protected":false},"excerpt":{"rendered":" A DC surge protective device (SPD) limits transient overvoltage and diverts surge current away from equipment. For solar PV, the key questions are where the device is installed, whether it is rated for the maximum PV open-circuit voltage at the lowest expected temperature, and how it coordinates with the inverter and other protective devices. This […]<\/p>\n","protected":false},"author":4,"featured_media":2529,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[42],"tags":[],"class_list":["post-2528","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-surge-protection-lightning-safety"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/posts\/2528","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/comments?post=2528"}],"version-history":[{"count":3,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/posts\/2528\/revisions"}],"predecessor-version":[{"id":4915,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/posts\/2528\/revisions\/4915"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/media\/2529"}],"wp:attachment":[{"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/media?parent=2528"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/categories?post=2528"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cnkuangya.com\/pt\/wp-json\/wp\/v2\/tags?post=2528"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Type 1 or Type 2: how to decide<\/h2>\n\n\n\n
Where to install protection in a PV system<\/h2>\n\n\n\n
Can an AC SPD be used on a DC circuit?<\/h2>\n\n\n\n
A practical PV SPD selection checklist<\/h2>\n\n\n\n
\n
What about batteries, EV chargers and telecom DC?<\/h2>\n\n\n\n
Price and procurement<\/h2>\n\n\n\n
Perguntas frequentes<\/h2>\n\n\n\n
Is a 1,100 V DC SPD suitable for a 1,000 V PV system?<\/h3>\n\n\n\n
Uma classifica\u00e7\u00e3o de kA maior significa sempre uma prote\u00e7\u00e3o melhor?<\/h3>\n\n\n\n
Conclus\u00e3o<\/h2>\n\n\n\n