PV \ucef4\ubc14\uc774\ub108 \ubc15\uc2a4<\/a> \uc0ac\uc774\uc9d5 \ubc0f DC \uc2a4\ud2b8\ub9c1 \ud4e8\uc9d5<\/h3>\n\n\n\n\uc804\uc555 \uc815\uaca9\uc744 \uacb0\uc815\ud55c \ud6c4 \ub2e4\uc74c \ub2e8\uacc4\ub294 \uc77c\ubc18\uc801\uc73c\ub85c \ud4e8\uc988\uc778 \uacfc\uc804\ub958 \ubcf4\ud638 \uc7a5\uce58(OCPD)\uc758 \ud06c\uae30\ub97c \uacb0\uc815\ud558\ub294 \uac83\uc785\ub2c8\ub2e4. \uc2a4\ud2b8\ub9c1 \ud4e8\uc988\uc758 \uc8fc\uc694 \ubaa9\uc801\uc740 \uc5ed\uc804\ub958\ub85c\ubd80\ud130 \ubcf4\ud638\ud558\ub294 \uac83\uc785\ub2c8\ub2e4. \ud55c \uc2a4\ud2b8\ub9c1\uc5d0 \uacb0\ud568\uc774 \ubc1c\uc0dd\ud558\uba74 \ub2e4\ub978 \uc2a4\ud2b8\ub9c1\uc5d0 \uc5ed\uc804\ub958\uac00 \ubc1c\uc0dd\ud558\uc5ec \uc704\ud5d8\ud55c \uacfc\uc804\ub958 \uc0c1\ud0dc\uac00 \ubc1c\uc0dd\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n\n\n\n
NEC 690.9\uc5d0 \ub530\ub77c \ub2e4\uc74c\uacfc \uac19\uc740 \uacbd\uc6b0 \uc2a4\ud2b8\ub9c1 \ub808\ubca8 \ud4e8\uc9d5\uc774 \ud544\uc694\ud569\ub2c8\ub2e4. \uc138 \uac1c \uc774\uc0c1\uc758 \ubb38\uc790\uc5f4\uc744 \ubcd1\ub82c\ub85c \uc5f0\uacb0<\/strong>. With only two strings, the reverse current potential is not high enough to exceed the module’s fuse rating, so fuses are not required by code (though they are still sometimes used as a disconnecting means).<\/p>\n\n\n\n\ubb38\uc790\uc5f4 \ud4e8\uc988 \ud06c\uae30\ub97c \uc870\uc815\ud558\ub294 \ubc29\ubc95:<\/strong><\/p>\n\n\n\nThe NEC requires that the fuse be rated to handle continuous duty and potential irradiance spikes. This is accomplished by multiplying the module’s Short-Circuit Current (Isc) by a factor of 1.56.<\/p>\n\n\n\n
\n1.25 \uacc4\uc218<\/strong> \uc5f0\uc18d \ubd80\ud558(3\uc2dc\uac04 \uc774\uc0c1 \uc791\ub3d9\ud560 \uc218 \uc788\ub294 \ud68c\ub85c)\uc758 \uacbd\uc6b0.<\/li>\n\n\n\n1.25 \uacc4\uc218<\/strong> for potential “irradiance enhancement” where sun exposure can exceed the standard 1000 W\/m\u00b2.<\/li>\n\n\n\n1.25 \u00d7 1.25 = 1.56<\/code><\/li>\n<\/ul>\n\n\n\n\ud4e8\uc988 \ub4f1\uae09 \uacf5\uc2dd:<\/strong> \ucd5c\uc18c \ud4e8\uc988 \uc815\uaca9 \u2265 \ubaa8\ub4c8 Isc \u00d7 1.56<\/code><\/p>\n\n\n\n\uc774 \ucd5c\uc18c\uac12\uc744 \uacc4\uc0b0\ud55c \ud6c4 \ub2e4\uc74c \ud45c\uc900 \ud4e8\uc988 \ud06c\uae30\ub97c \uc120\ud0dd\ud569\ub2c8\ub2e4.<\/p>\n\n\n\n
\uc911\uc694\ud55c \uc81c\ud55c \uc0ac\ud56d: \ucd5c\ub300 \uc9c1\ub82c \ud4e8\uc988 \uc815\uaca9<\/strong>\\\uacc4\uc0b0\ub41c \ud4e8\uc988 \ud06c\uae30\ub294 \uc774 \uc815\uaca9\uc744 \ucd08\uacfc\ud558\uc9c0 \uc54a\uc544\uc57c \ud569\ub2c8\ub2e4.<\/strong> \uc774 \uacbd\uc6b0 \uc2dc\uc2a4\ud15c \uc124\uacc4\uc5d0 \uacb0\ud568\uc774 \uc788\ub294 \uac83\uc73c\ub85c, \uc77c\ubc18\uc801\uc73c\ub85c \uc120\ud0dd\ud55c \ubaa8\ub4c8\uc744 \uadf8\ub807\uac8c \ub9ce\uc740 \ubb38\uc790\uc5f4\uc744 \ubcd1\ub82c\ub85c \uc0ac\uc6a9\ud560 \uc218 \uc5c6\ub2e4\ub294 \uc758\ubbf8\uc785\ub2c8\ub2e4.<\/p>\n\n\n\n\uc608\uc2dc:<\/strong><\/p>\n\n\n\n\n\ubaa8\ub4c8 Isc: 10.5A<\/li>\n\n\n\n \ubaa8\ub4c8 \ucd5c\ub300 \uc9c1\ub82c \ud4e8\uc988 \uc815\uaca9: 20A<\/li>\n\n\n\n \ucd5c\uc18c \ud4e8\uc988 \uc815\uaca9 = 10.5A \u00d7 1.56<\/code> = 16.38A<\/strong><\/li>\n<\/ul>\n\n\n\n\uc774 \uacc4\uc0b0\uc5d0 \ub530\ub77c \ub2e4\uc74c \ud45c\uc900 \uc0ac\uc774\uc988 \uc5c5\uc778 20A<\/strong> fuse. Since 20A is equal to the module’s maximum series fuse rating, this is a valid selection. If the calculation had resulted in 21A, you would not be able to use a 25A fuse, and the design would need to be re-evaluated.<\/p>\n\n\n\n3\ubd80: \uacfc\uc804\ub958 \ubcf4\ud638 \uc870\uc815<\/h3>\n\n\n\n \ubcf4\ud638 \uc870\uc815\uc740 \uc7a5\uc560 \ubc1c\uc0dd \uc2dc \uc62c\ubc14\ub978 OCPD\uac00 \uba3c\uc800 \uc5f4\ub9ac\ub3c4\ub85d \ubcf4\uc7a5\ud569\ub2c8\ub2e4. \ub2e8\uc77c \uc2a4\ud2b8\ub9c1 \ub0b4 \uace0\uc7a5\uc758 \uacbd\uc6b0 \uac1c\ubcc4 \uc2a4\ud2b8\ub9c1 \ud4e8\uc988\uac00 \ub04a\uc5b4\uc838 \uc804\uccb4 \uc5b4\ub808\uc774\ub97c \uc624\ud504\ub77c\uc778\uc73c\ub85c \uc804\ud658\ud558\uc9c0 \uc54a\uace0 \ud574\ub2f9 \uc2a4\ud2b8\ub9c1\ub9cc \ubd84\ub9ac\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4. \ucef4\ubc14\uc774\ub108 \ubc15\uc2a4 \ucd9c\ub825\uc758 \uba54\uc778 OCPD\ub294 \uc778\ubc84\ud130\ub85c \uc5f0\uacb0\ub418\ub294 \uba54\uc778 \ucee8\ub355\ud130\uc5d0 \uc911\ub300\ud55c \uacb0\ud568\uc774 \uc788\ub294 \uacbd\uc6b0\uc5d0\ub9cc \ud2b8\ub9bd\ub418\uc5b4\uc57c \ud569\ub2c8\ub2e4.<\/p>\n\n\n\n
\uc774\ub294 \ub2e4\uc6b4\uc2a4\ud2b8\ub9bc \ub514\ubc14\uc774\uc2a4\uac00 \uc5c5\uc2a4\ud2b8\ub9bc \ub514\ubc14\uc774\uc2a4\ubcf4\ub2e4 \ub0ae\uc740 \ub4f1\uae09\uc744 \uac16\ub3c4\ub85d \ud558\uc5ec \ub2ec\uc131\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.<\/p>\n\n\n\n\uad6c\uc131 \uc694\uc18c<\/strong><\/th>\ubaa9\uc801<\/strong><\/th>\ud06c\uae30 \uc870\uc815 \uacbd\ud5d8 \ubc95\uce59<\/strong><\/th>NEC \ucc38\uc870<\/strong><\/th><\/tr><\/thead>\ubb38\uc790\uc5f4 \ud4e8\uc988<\/strong><\/td>\ub2e4\ub978 \uc2a4\ud2b8\ub9c1\uc758 \uc5ed\uc804\ub958 \uc624\ub958\ub85c\ubd80\ud130 \uac1c\ubcc4 \uc2a4\ud2b8\ub9c1\uc744 \ubcf4\ud638\ud569\ub2c8\ub2e4.<\/td> Isc \u00d7 1.56<\/code> (\ubaa8\ub4c8 \ucd5c\ub300 \ud4e8\uc988 \uc815\uaca9 \u2264\uc774\uc5b4\uc57c \ud568)<\/td>690.9(A)<\/code><\/td><\/tr>\uba54\uc778 \ucef4\ubc14\uc774\ub108 OCPD<\/strong><\/td>\ucef4\ubc14\uc774\ub108 \ubc15\uc2a4\uc5d0\uc11c \uc778\ubc84\ud130\ub85c \uc5f0\uacb0\ub418\ub294 \uba54\uc778 \ucd9c\ub825 \uc640\uc774\uc5b4\ub97c \ubcf4\ud638\ud569\ub2c8\ub2e4.<\/td> \ubaa8\ub4e0 \uc2a4\ud2b8\ub9c1 \ud4e8\uc988 \uc815\uaca9\uc758 \ud569\uc73c\ub85c, \uac00\uc7a5 \uac00\uae4c\uc6b4 \ud45c\uc900 \ucc28\ub2e8\uae30 \ud06c\uae30\ub85c \ubc18\uc62c\ub9bc\ud569\ub2c8\ub2e4. \ub610\ub294 (\ucd1d Isc \u00d7 1.25)<\/code> \ub97c \ud074\ub9ad\ud558\uace0 \ub2e4\uc74c \ud45c\uc900 OCPD \ud06c\uae30 \uc5c5\uc744 \uc120\ud0dd\ud569\ub2c8\ub2e4.<\/td>690.9(A)<\/code> & 240.4<\/code><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n\uc790\uc8fc \ubb3b\ub294 \uc9c8\ubb38(FAQ)<\/h3>\n\n\n\n \ub450 \uac1c\uc758 \ubcd1\ub82c \uc2a4\ud2b8\ub9c1\uc5d0\ub9cc \ud4e8\uc988\uac00 \ud544\uc694\ud55c\uac00\uc694?<\/strong>\\DC \ud68c\ub85c\uc5d0 AC \ub4f1\uae09 \ud4e8\uc988 \ub610\ub294 \ucc28\ub2e8\uae30\ub97c \uc0ac\uc6a9\ud560 \uc218 \uc788\ub098\uc694?<\/strong>\\\ud4e8\uc988 \ud06c\uae30\ub97c \uc798\ubabb \uc124\uce58\ud558\uba74 \uc5b4\ub5bb\uac8c \ub418\ub098\uc694?<\/strong><\/p>\n\n\n\n\n\ub108\ubb34 \uc791\uc2b5\ub2c8\ub2e4:<\/strong> The fuse will be subject to “nuisance tripping,” blowing under normal operating conditions (e.g., on a cool, very sunny day), causing unnecessary system downtime.<\/li>\n\n\n\n\ub108\ubb34 \ud07d\ub2c8\ub2e4:<\/strong> A fuse that is too large (especially one exceeding the module’s Maximum Series Fuse Rating) will not protect the module from damaging reverse currents. This can lead to module failure and creates a fire risk.<\/li>\n<\/ul>\n\n\n\n\ud06c\uae30 \uc870\uc815\uc5d0 1.56 \uc2b9\uc218\ub97c \uc0ac\uc6a9\ud558\ub294 \uc774\uc720\ub294 \ubb34\uc5c7\uc778\uac00\uc694?<\/strong>\\\ubaa8\ub4c8\uc758 \u201c\ucd5c\ub300 \uc9c1\ub82c \ud4e8\uc988 \uc815\uaca9\u201d\uc774\ub780 \ubb34\uc5c7\uc778\uac00\uc694?<\/strong>\\\uacb0\ub860<\/h3>\n\n\n\n Matching a PV combiner box’s current and voltage ratings is a systematic process guided by engineering principles and the strict safety standards of the NEC. The core takeaways are:<\/p>\n\n\n\n
\n\uc804\uc555 \uc6b0\uc120:<\/strong> \ud56d\uc0c1 \uc0ac\uc774\ud2b8\uc758 \uc608\uc0c1 \ucd5c\uc800 \uc628\ub3c4\ub97c \uc0ac\uc6a9\ud558\uc5ec \ucd5c\ub300 \uc2dc\uc2a4\ud15c \uc804\uc555\uc744 \uacb0\uc815\ud558\uc138\uc694. \ubaa8\ub4e0 \uad6c\uc131 \uc694\uc18c\ub294 \uc774 \uc804\uc555\uc5d0 \ub9de\uac8c \uc815\uaca9\ud654\ub418\uc5b4\uc57c \ud569\ub2c8\ub2e4.<\/li>\n\n\n\n\ud604\uc7ac \ucd08:<\/strong> Size string fuses based on the module’s Isc and the 1.56x multiplier, but never exceed the module’s Maximum Series Fuse Rating.<\/li>\n\n\n\n\ucf54\ub4dc\uac00 \ud575\uc2ec\uc785\ub2c8\ub2e4:<\/strong> When in doubt, defer to NEC Article 690 and the manufacturer’s datasheets for all components.<\/li>\n<\/ol>\n\n\n\nBy following these guidelines, you can ensure your solar array’s combiner box is sized safely, reliably, and professionally, forming a robust foundation for your entire PV system.<\/p>","protected":false},"excerpt":{"rendered":"
In a solar photovoltaic (PV) system, the combiner box plays a central role in consolidating power and ensuring safety. It’s a junction box where the output of multiple solar strings are connected in parallel, combining their current before sending it to the inverter. More importantly, it houses the critical overcurrent protection devices (fuses or circuit […]<\/p>","protected":false},"author":4,"featured_media":2285,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35],"tags":[],"class_list":["post-2279","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/cnkuangya.com\/ko\/wp-json\/wp\/v2\/posts\/2279","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cnkuangya.com\/ko\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cnkuangya.com\/ko\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cnkuangya.com\/ko\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/cnkuangya.com\/ko\/wp-json\/wp\/v2\/comments?post=2279"}],"version-history":[{"count":1,"href":"https:\/\/cnkuangya.com\/ko\/wp-json\/wp\/v2\/posts\/2279\/revisions"}],"predecessor-version":[{"id":2283,"href":"https:\/\/cnkuangya.com\/ko\/wp-json\/wp\/v2\/posts\/2279\/revisions\/2283"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cnkuangya.com\/ko\/wp-json\/wp\/v2\/media\/2285"}],"wp:attachment":[{"href":"https:\/\/cnkuangya.com\/ko\/wp-json\/wp\/v2\/media?parent=2279"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cnkuangya.com\/ko\/wp-json\/wp\/v2\/categories?post=2279"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cnkuangya.com\/ko\/wp-json\/wp\/v2\/tags?post=2279"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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