{"id":4474,"date":"2026-09-07T10:43:34","date_gmt":"2026-09-07T02:43:34","guid":{"rendered":"https:\/\/cnkuangya.com\/?p=4474"},"modified":"2026-09-07T16:20:23","modified_gmt":"2026-09-07T08:20:23","slug":"why-spd-connected-in-parallel","status":"publish","type":"post","link":"https:\/\/cnkuangya.com\/ja\/blog\/why-spd-connected-in-parallel\/","title":{"rendered":"\u306a\u305cSPD\u306f\u76f4\u5217\u3067\u306f\u306a\u304f\u4e26\u5217\u306b\u63a5\u7d9a\u3055\u308c\u308b\u306e\u304b\uff1f"},"content":{"rendered":"<p class=\"wp-block-paragraph\">\u4e00\u822c\u7684\u306a\u30b5\u30fc\u30b8\u9632\u8b77\u30c7\u30d0\u30a4\u30b9\uff08SPD\uff09\u306e\u8a2d\u7f6e\u72b6\u6cc1\u3092\u898b\u308b\u3068\u3001\u30d2\u30e5\u30fc\u30ba\u3084\u914d\u7dda\u7528\u906e\u65ad\u5668\uff08MCCB\uff09\u3068\u306f\u7570\u306a\u308b\u70b9\u304c\u3042\u308b\u3053\u3068\u306b\u6c17\u3065\u304f\u304b\u3082\u3057\u308c\u307e\u305b\u3093\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u30d2\u30e5\u30fc\u30ba\u3084\u914d\u7dda\u7528\u906e\u65ad\u5668\u306f\u901a\u5e38\u3001\u56de\u8def\u306b\u5bfe\u3057\u3066\u76f4\u5217\u306b\u8a2d\u7f6e\u3055\u308c\u308b\u305f\u3081\u3001\u8ca0\u8377\u96fb\u6d41\u306f\u305d\u308c\u3089\u3092\u901a\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e00\u822c\u7684\u306a\u96fb\u6e90\u7528SPD\u306f\u901a\u5e38\u3001 <strong>\u4e26\u5217\u306b\u63a5\u7d9a\u3055\u308c\u307e\u3059<\/strong> \u4fdd\u8b77\u5bfe\u8c61\u306e\u56de\u8def\u306b\u5bfe\u3057\u3066\u3002\u3053\u308c\u304c\u3001\u591a\u304f\u306e\u65bd\u5de5\u8005\u304c\u306a\u305c <strong>SPD\u304c\u76f4\u5217\u3067\u306f\u306a\u304f\u4e26\u5217\u306b\u63a5\u7d9a\u3055\u308c\u308b\u306e\u304b\u3068\u7591\u554f\u306b\u601d\u3046\u7406\u7531\u3067\u3059\u3002<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u306a\u305c\u3067\u3059\u304b\uff1f<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7c21\u6f54\u306b\u8a00\u3048\u3070\u3001\u4e26\u5217\u63a5\u7d9a\u3055\u308c\u305fSPD\u306f\u901a\u5e38\u306e\u8ca0\u8377\u96fb\u6d41\u3092\u6d41\u3059\u5fc5\u8981\u304c\u306a\u3044\u305f\u3081\u3067\u3059\u3002\u901a\u5e38\u52d5\u4f5c\u6761\u4ef6\u4e0b\u3067\u306f\u3001SPD\u306f\u9ad8\u30a4\u30f3\u30d4\u30fc\u30c0\u30f3\u30b9\u72b6\u614b\u3092\u7dad\u6301\u3057\u307e\u3059\u3002\u904e\u6e21\u904e\u96fb\u5727\u304c\u767a\u751f\u3059\u308b\u3068\u3001SPD\u306f\u5c0e\u901a\u3092\u958b\u59cb\u3057\u3001\u30b5\u30fc\u30b8\u96fb\u6d41\u306b\u5bfe\u3057\u3066\u4f4e\u30a4\u30f3\u30d4\u30fc\u30c0\u30f3\u30b9\u306e\u7d4c\u8def\u3092\u63d0\u4f9b\u3059\u308b\u3053\u3068\u3067\u3001\u4fdd\u8b77\u5bfe\u8c61\u6a5f\u5668\u306b\u5230\u9054\u3059\u308b\u96fb\u5727\u3092\u5236\u9650\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u304c\u3001\u914d\u96fb\u30b7\u30b9\u30c6\u30e0\u3084\u592a\u967d\u5149\u767a\u96fb\u30b7\u30b9\u30c6\u30e0\u306b\u304a\u3044\u3066\u3001\u30bf\u30a4\u30d71\u304a\u3088\u3073\u30bf\u30a4\u30d72\u306eSPD\u306b\u4e26\u5217\u63a5\u7d9a\u304c\u5e83\u304f\u63a1\u7528\u3055\u308c\u3066\u3044\u308b\u7406\u7531\u3067\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u305f\u3060\u3057\u3001\u300cSPD\uff1d\u5e38\u306b\u4e26\u5217\u300d\u3068\u3044\u3046\u308f\u3051\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002\u7279\u5b9a\u306e\u7528\u9014\u5411\u3051\u306b\u306f\u3001\u76f4\u5217\u63a5\u7d9a\u578b\u306eSPD\u3084\u30b5\u30fc\u30b8\u30d5\u30a3\u30eb\u30bf\u3082\u5b58\u5728\u3057\u307e\u3059\u3002\u672c\u8a18\u4e8b\u3067\u306f\u3001\u4e3b\u306b\u4ea4\u6d41\u914d\u96fb\u30b7\u30b9\u30c6\u30e0\u3084\u592a\u967d\u5149\u767a\u96fbDC\u30b7\u30b9\u30c6\u30e0\u3067\u4f7f\u7528\u3055\u308c\u308b\u4e00\u822c\u7684\u306a\u4e26\u5217\u63a5\u7d9a\u578b\u96fb\u6e90\u7528SPD\u306b\u3064\u3044\u3066\u89e3\u8aac\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u30af\u30a4\u30c3\u30af\u30a2\u30f3\u30b5\u30fc\uff1aSPD\u306e\u4e26\u5217\u63a5\u7d9a\u3068\u76f4\u5217\u63a5\u7d9a\u306e\u6bd4\u8f03<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u5178\u578b\u7684\u306a\u4f8b <strong>\u4e26\u5217\u63a5\u7d9a\u3055\u308c\u305fSPD<\/strong> \u8ca0\u8377\u306e\u901a\u5e38\u52d5\u4f5c\u96fb\u6d41\u3092\u6d41\u3059\u3053\u3068\u306a\u304f\u3001\u904e\u6e21\u904e\u96fb\u5727\u30a4\u30d9\u30f3\u30c8\u306b\u5fdc\u7b54\u3059\u308b\u3088\u3046\u306b\u8a2d\u8a08\u3055\u308c\u3066\u3044\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u901a\u5e38\u306e\u72b6\u614b\u3067\u306f<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u96fb\u6e90 \u2192 \u8ca0\u8377<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">SPD\u306f\u5f85\u6a5f\u72b6\u614b\u3092\u7dad\u6301\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u30b5\u30fc\u30b8\u304c\u767a\u751f\u3059\u308b\u3068\u3001SPD\u306f\u305d\u306e\u96fb\u6c17\u7684\u7279\u6027\u3092\u5909\u5316\u3055\u305b\u3001\u4fdd\u8b77\u7d4c\u8def\u3092\u901a\u3058\u3066\u30b5\u30fc\u30b8\u96fb\u6d41\u3092\u9003\u304c\u3059\u3053\u3068\u3067\u3001\u654f\u611f\u306a\u6a5f\u5668\u306b\u5370\u52a0\u3055\u308c\u308b\u96fb\u5727\u3092\u5236\u9650\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7c21\u7565\u5316\u3057\u305f\u4e26\u5217\u63a5\u7d9a\u306e\u69cb\u6210\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u96fb\u6e90 \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 \u8ca0\u8377\n<\/code><\/pre>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"683\" src=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-parallel-connection-wiring-1024x683.jpg\" alt=\"SPD parallel connection wiring in an electrical distribution system\" class=\"wp-image-4476\" srcset=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-parallel-connection-wiring-1024x683.jpg 1024w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-parallel-connection-wiring-300x200.jpg 300w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-parallel-connection-wiring-768x512.jpg 768w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-parallel-connection-wiring-18x12.jpg 18w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-parallel-connection-wiring-600x400.jpg 600w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-parallel-connection-wiring.jpg 1536w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">\u4e00\u822c\u7684\u306a\u4e26\u5217\u63a5\u7d9a\u578bSPD\u306f\u3001\u901a\u5e38\u306e\u8ca0\u8377\u96fb\u6d41\u7d4c\u8def\u306b\u76f4\u63a5\u633f\u5165\u3059\u308b\u306e\u3067\u306f\u306a\u304f\u3001\u4fdd\u8b77\u5bfe\u8c61\u56de\u8def\u306b\u5bfe\u3057\u3066\u4e26\u5217\u306b\u8a2d\u7f6e\u3055\u308c\u307e\u3059\u3002.<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">SPD\u306f\u901a\u5e38\u306e\u8ca0\u8377\u96fb\u6d41\u7d4c\u8def\u306b\u76f4\u63a5\u633f\u5165\u3055\u308c\u308b\u306e\u3067\u306f\u306a\u304f\u3001\u56de\u8def\u306b\u5bfe\u3057\u3066\u4e26\u5217\u306b\u63a5\u7d9a\u3055\u308c\u307e\u3059\u3002. <strong><a href=\"https:\/\/www.phoenixcontact.com\/assets\/c8428ddc-254d-40b8-a2f2-540ac13bd818\/index.html#0\" rel=\"noopener\">\u30d5\u30a8\u30cb\u30c3\u30af\u30b9\u30fb\u30b3\u30f3\u30bf\u30af\u30c8\u306e\u30b5\u30fc\u30b8\u4fdd\u8b77\u306e\u57fa\u790e<\/a><\/strong> \u307e\u305f\u3001SPD\u306f\u4fdd\u8b77\u5bfe\u8c61\u6a5f\u5668\u3068\u4e26\u5217\u306b\u3001\u3042\u308b\u3044\u306f\u95a2\u9023\u3059\u308b\u5c0e\u4f53\u9593\u306b\u8a2d\u7f6e\u3067\u304d\u308b\u3068\u8aac\u660e\u3057\u3066\u3044\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u30a4\u30fc\u30c8\u30f3\u793e\u3082\u540c\u69d8\u306b\u3001\u4e26\u5217\u63a5\u7d9a\uff08\u307e\u305f\u306f\u30b7\u30e3\u30f3\u30c8\u63a5\u7d9a\uff09\u578bSPD\u306b\u3064\u3044\u3066\u3001\u63a5\u7d9a\u5c0e\u4f53\u306b\u306f\u901a\u5e38\u306e\u4f9b\u7d66\u96fb\u6d41\u306f\u6d41\u308c\u305a\u3001\u904e\u6e21\u73fe\u8c61\u306b\u4f34\u3046\u77ed\u6642\u9593\u306e\u96fb\u6d41\u306e\u307f\u304c\u6d41\u308c\u308b\u3068\u8aac\u660e\u3057\u3066\u3044\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u306e\u57fa\u672c\u7684\u306a\u9055\u3044\u304c\u3001\u4e00\u822c\u7684\u306a\u96fb\u6e90\u7528SPD\u306e\u307b\u3068\u3093\u3069\u304c\u4e26\u5217\u306b\u8a2d\u7f6e\u3055\u308c\u308b\u7406\u7531\u3092\u8aac\u660e\u3057\u3066\u3044\u307e\u3059\u3002.<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-9-16 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe loading=\"lazy\" title=\"Why is an SPD connected in parallel instead of series?\" width=\"563\" height=\"1000\" src=\"https:\/\/www.youtube.com\/embed\/itkgmV2pQ98?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><figcaption class=\"wp-element-caption\">\u901a\u5e38\u306e\u52d5\u4f5c\u6642\u304a\u3088\u3073\u30b5\u30fc\u30b8\u767a\u751f\u6642\u306b\u304a\u3051\u308b\u4e00\u822c\u7684\u306aSPD\u306e\u6319\u52d5\u3092\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\u3002.<\/figcaption><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u901a\u5e38\u52d5\u4f5c\u4e2d\u3001SPD\u306b\u306f\u4f55\u304c\u8d77\u3053\u308b\u306e\u304b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e26\u5217\u63a5\u7d9a\u3092\u7406\u89e3\u3059\u308b\u306b\u306f\u3001\u307e\u305a\u30b5\u30fc\u30b8\u304c\u767a\u751f\u3057\u3066\u3044\u306a\u3044\u6642\u306bSPD\u304c\u3069\u306e\u3088\u3046\u306a\u72b6\u614b\u306b\u3042\u308b\u304b\u3092\u7406\u89e3\u3059\u308b\u3053\u3068\u304c\u5f79\u7acb\u3061\u307e\u3059\u3002.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u901a\u5e38\u306e\u30b7\u30b9\u30c6\u30e0\u96fb\u5727\u4e0b\u306b\u304a\u3044\u3066<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u901a\u5e38\u52d5\u4f5c\u4e2d\u3001\u30b7\u30b9\u30c6\u30e0\u96fb\u5727\u306fSPD\u304c\u6709\u610f\u306b\u5c0e\u901a\u3059\u308b\u30ec\u30d9\u30eb\u3092\u4e0b\u56de\u3063\u305f\u307e\u307e\u3067\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">MOV\u30d9\u30fc\u30b9\u306eSPD\u306e\u5834\u5408\u3001\u4fdd\u8b77\u7d20\u5b50\u306f\u901a\u5e38\u96fb\u5727\u6761\u4ef6\u4e0b\u3067\u6bd4\u8f03\u7684\u9ad8\u3044\u30a4\u30f3\u30d4\u30fc\u30c0\u30f3\u30b9\u3092\u793a\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u306f\u3001\u4e3b\u52d5\u4f5c\u96fb\u6d41\u304c\u901a\u5e38\u306e\u96fb\u6e90\u56de\u8def\u3092\u901a\u3063\u3066\u8ca0\u8377\u3078\u3068\u6d41\u308c\u7d9a\u3051\u308b\u3053\u3068\u3092\u610f\u5473\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">SPD\u306f\u672c\u8cea\u7684\u306b\u5f85\u6a5f\u72b6\u614b\u306b\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7c21\u7565\u5316\u3057\u305f\u56f3\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u96fb\u6e90 \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 \u8ca0\u8377\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u306f\u3001\u3059\u3079\u3066\u306eSPD\u306b\u96fb\u6d41\u304c\u5168\u304f\u6d41\u308c\u306a\u3044\u3053\u3068\u3092\u610f\u5473\u3059\u308b\u308f\u3051\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002SPD\u306e\u6280\u8853\u3084\u8a2d\u8a08\u306b\u3088\u3063\u3066\u306f\u3001\u308f\u305a\u304b\u306a\u6f0f\u308c\u96fb\u6d41\u3084\u52d5\u4f5c\u96fb\u6d41\u304c\u5b58\u5728\u3059\u308b\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u91cd\u8981\u306a\u70b9\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u901a\u5e38\u306e\u8ca0\u8377\u96fb\u6d41\u306f\u3001\u4e00\u822c\u7684\u306a\u4e26\u5217\u63a5\u7d9a\u3055\u308c\u305fSPD\u3092\u6d41\u308c\u308b\u5fc5\u8981\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Think of the SPD as a protection path waiting beside the main circuit rather than a component that must continuously carry the equipment&#8217;s operating current.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u30b5\u30fc\u30b8\u304c\u767a\u751f\u3059\u308b\u3068\u3069\u3046\u306a\u308b\u304b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u30b5\u30fc\u30b8\u3068\u306f\u3001\u843d\u96f7\u306b\u95a2\u9023\u3059\u308b\u904e\u6e21\u73fe\u8c61\u3084\u958b\u9589\u64cd\u4f5c\u306a\u3069\u306e\u4e8b\u8c61\u306b\u3088\u3063\u3066\u5f15\u304d\u8d77\u3053\u3055\u308c\u308b\u3001\u77ed\u6642\u9593\u306e\u96fb\u5727\u4e0a\u6607\u306e\u3053\u3068\u3067\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When the voltage across the SPD rises sufficiently, the SPD&#8217;s protection elements begin conducting.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4fdd\u8b77\u7d20\u5b50\u304c\u904e\u6e21\u904e\u96fb\u5727\u306b\u3069\u306e\u3088\u3046\u306b\u5fdc\u7b54\u3059\u308b\u304b\u306b\u3064\u3044\u3066\u306e\u8a73\u7d30\u306a\u8aac\u660e\u306f\u3001\u5f53\u793e\u306e\u30ac\u30a4\u30c9\u3092\u53c2\u7167\u3057\u3066\u304f\u3060\u3055\u3044\u3002 <strong><a href=\"https:\/\/cnkuangya.com\/ja\/%e3%83%96%e3%83%ad%e3%82%b0\/how-dc-spd-works-operating-principles-components-engineers-guide\/\">DC SPD\u306e\u4ed5\u7d44\u307f<\/a><\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u306e\u30a4\u30f3\u30d4\u30fc\u30c0\u30f3\u30b9\u306f\u3001\u901a\u5e38\u306e\u72b6\u614b\u3068\u6bd4\u8f03\u3057\u3066\u6025\u6fc0\u306b\u4f4e\u4e0b\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u306b\u3088\u308a\u3001\u30b5\u30fc\u30b8\u96fb\u6d41\u304c\u5229\u7528\u53ef\u80fd\u306a\u4fdd\u8b77\u7d4c\u8def\u3092\u901a\u3063\u3066\u6d41\u308c\u3001\u4fdd\u8b77\u5bfe\u8c61\u6a5f\u5668\u306b\u767a\u751f\u3059\u308b\u904e\u6e21\u96fb\u5727\u3092\u5236\u9650\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u7c21\u7565\u5316\u3057\u305f\u56f3\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>                 \u6a5f\u5668\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u305f\u3060\u3057\u3001\u3053\u306e\u56f3\u306f\u3042\u304f\u307e\u3067\u7c21\u7565\u5316\u3055\u308c\u305f\u4f8b\u3067\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">SPD\u306f <strong>\u3059\u3079\u3066\u306e\u30b5\u30fc\u30b8\u3092\u76f4\u63a5\u63a5\u5730\u3078\u9003\u304c\u305b\u308b\u3068\u306f\u9650\u3089\u306a\u3044<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u96fb\u6c17\u30b7\u30b9\u30c6\u30e0\u304a\u3088\u3073SPD\u306e\u8a2d\u8a08\u306b\u5fdc\u3058\u3066\u3001\u4ee5\u4e0b\u306e\u4fdd\u8b77\u30e2\u30fc\u30c9\u304c\u5b58\u5728\u3059\u308b\u5834\u5408\u304c\u3042\u308b\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u76f8\u304a\u3088\u3073\u4e2d\u6027\u7dda<\/li>\n\n\n\n<li>\u76f8\u304a\u3088\u3073\u4fdd\u8b77\u63a5\u5730\u7dda<\/li>\n\n\n\n<li>\u4e2d\u6027\u7dda\u304a\u3088\u3073\u4fdd\u8b77\u63a5\u5730\u7dda<\/li>\n\n\n\n<li>\u76f8\u304a\u3088\u3073\u76f8<\/li>\n\n\n\n<li>DC\u30d7\u30e9\u30b9\u304a\u3088\u3073DC\u30de\u30a4\u30ca\u30b9<\/li>\n\n\n\n<li>DC\u5c0e\u4f53\u304a\u3088\u3073\u4fdd\u8b77\u63a5\u5730\u7dda\uff08PE\uff09<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u306e\u305f\u3081\u3001\u6b21\u306e\u3088\u3046\u306b\u8868\u73fe\u3059\u308b\u65b9\u304c\u3088\u308a\u6b63\u78ba\u3067\u3059\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>SPD\u306f\u30b5\u30fc\u30b8\u96fb\u6d41\u306b\u5bfe\u3057\u3066\u5236\u5fa1\u3055\u308c\u305f\u7d4c\u8def\u3092\u63d0\u4f9b\u3057\u3001\u4fdd\u8b77\u5bfe\u8c61\u6a5f\u5668\u306b\u304b\u304b\u308b\u904e\u6e21\u96fb\u5727\u3092\u5236\u9650\u3057\u307e\u3059\u3002.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u6b63\u78ba\u306a\u96fb\u6d41\u7d4c\u8def\u306f\u3001SPD\u306e\u69cb\u6210\u304a\u3088\u3073\u30b7\u30b9\u30c6\u30e0\u30c8\u30dd\u30ed\u30b8\u30fc\u306b\u4f9d\u5b58\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u306a\u305cSPD\u306f\u4e26\u5217\u306b\u63a5\u7d9a\u3055\u308c\u308b\u306e\u304b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">SPD\u304c\u4e26\u5217\u306b\u63a5\u7d9a\u3055\u308c\u308b\u7406\u7531\u3092\u7406\u89e3\u3059\u308b\u306b\u306f\u3001\u901a\u5e38\u52d5\u4f5c\u6642\u3068\u30b5\u30fc\u30b8\u767a\u751f\u6642\u306e\u4e21\u65b9\u3067\u4f55\u304c\u8d77\u3053\u308b\u304b\u3092\u78ba\u8a8d\u3059\u308b\u3053\u3068\u304c\u5f79\u7acb\u3061\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3044\u304f\u3064\u304b\u306e\u91cd\u8981\u306a\u7406\u7531\u306b\u3088\u308a\u3001 <strong>\u4e26\u5217\u63a5\u7d9a\u3055\u308c\u305fSPD<\/strong> \u306f\u914d\u96fb\u30b7\u30b9\u30c6\u30e0\u3067\u5e83\u304f\u4f7f\u7528\u3055\u308c\u3066\u3044\u307e\u3059\u3002.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">1. SPD\u306f\u901a\u5e38\u306e\u8ca0\u8377\u96fb\u6d41\u3092\u6d41\u3059\u5fc5\u8981\u304c\u306a\u3044<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u306f\u3001SPD\u3068\u56de\u8def\u906e\u65ad\u5668\u3084\u30d2\u30e5\u30fc\u30ba\u306a\u3069\u306e\u30c7\u30d0\u30a4\u30b9\u3068\u306e\u9593\u306e\u6700\u3082\u5927\u304d\u306a\u9055\u3044\u306e\u4e00\u3064\u3067\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u30a4\u30f3\u30d0\u30fc\u30bf\u304c\u901a\u5e38\u6570\u5341\u30a2\u30f3\u30da\u30a2\u3067\u52d5\u4f5c\u3057\u3066\u3044\u308b\u3068\u60f3\u50cf\u3057\u3066\u304f\u3060\u3055\u3044\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e00\u822c\u7684\u306a\u4e26\u5217\u63a5\u7d9a\u578bSPD\u306e\u5834\u5408\u3001\u305d\u306e\u52d5\u4f5c\u96fb\u6d41\u304cSPD\u3092\u7d99\u7d9a\u7684\u306b\u901a\u904e\u3059\u308b\u5fc5\u8981\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u306e\u4ee3\u308f\u308a\u3060\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u96fb\u6e90 \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 \u8ca0\u8377\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">SPD\u306f\u4fdd\u8b77\u5bfe\u8c61\u306e\u56de\u8def\u306b\u5bfe\u3057\u3066\u4e26\u5217\u306b\u63a5\u7d9a\u3055\u308c\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3064\u307e\u308a\u3001SPD\u306f\u4e0b\u6d41\u306e\u3059\u3079\u3066\u306e\u8ca0\u8377\u306e\u5168\u52d5\u4f5c\u96fb\u6d41\u306b\u57fa\u3065\u3044\u3066\u9078\u5b9a\u3059\u308b\u306e\u3067\u306f\u306a\u304f\u3001\u4e3b\u306b\u30b5\u30fc\u30b8\u4fdd\u8b77\u8981\u4ef6\u306b\u57fa\u3065\u3044\u3066\u9078\u5b9a\u3067\u304d\u308b\u3053\u3068\u3092\u610f\u5473\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Phoenix Contact similarly notes that its parallel-installed power SPDs appear electrically as a branch connected across the power distribution system rather than carrying the circuit&#8217;s normal ampacity.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">2. SPD\u306f\u4e3b\u306b\u904e\u96fb\u5727\u30a4\u30d9\u30f3\u30c8\u306b\u5fdc\u7b54\u3059\u308b<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e00\u822c\u7684\u306aSPD\u306f\u96fb\u5727\u611f\u5fdc\u578b\u3067\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u901a\u5e38\u306e\u30b7\u30b9\u30c6\u30e0\u96fb\u5727\u4e0b\u3067\u306f\u3001SPD\u306f\u307b\u3068\u3093\u3069\u52d5\u4f5c\u3057\u307e\u305b\u3093\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u904e\u6e21\u96fb\u5727\u304c\u901a\u5e38\u306e\u52d5\u4f5c\u7bc4\u56f2\u3092\u8d85\u3048\u3066\u4e0a\u6607\u3059\u308b\u3068\u3001\u4fdd\u8b77\u7d20\u5b50\u304c\u5c0e\u901a\u3092\u958b\u59cb\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u306f\u3001\u30d2\u30e5\u30fc\u30ba\u3001\u914d\u7dda\u7528\u906e\u65ad\u5668\u3001\u307e\u305f\u306f\u65ad\u8def\u5668\u3068\u306f\u6839\u672c\u7684\u306b\u7570\u306a\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f8b\u3048\u3070\u3001\u3053\u3046\u3060\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u30d2\u30e5\u30fc\u30ba<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u96fb\u6e90 \u2192 \u30d2\u30e5\u30fc\u30ba \u2192 \u8ca0\u8377\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u914d\u7dda\u7528\u906e\u65ad\u5668<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u96fb\u6e90 \u2192 \u906e\u65ad\u5668 \u2192 \u8ca0\u8377\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u4e00\u822c\u7684\u306a\u4e26\u5217\u63a5\u7d9a\u578bSPD<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u96fb\u6e90 \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 \u8ca0\u8377\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u30d2\u30e5\u30fc\u30ba\u3084\u906e\u65ad\u5668\u306f\u7269\u7406\u7684\u306b\u8ca0\u8377\u7d4c\u8def\u306b\u914d\u7f6e\u3055\u308c\u3066\u3044\u308b\u305f\u3081\u3001\u901a\u5e38\u306f\u56de\u8def\u96fb\u6d41\u3092\u6d41\u3059\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e26\u5217\u63a5\u7d9a\u578bSPD\u306f\u305d\u3046\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e26\u5217\u63a5\u7d9a\u306f\u30b5\u30fc\u30b8\u96fb\u6d41\u306e\u7d4c\u8def\u3092\u63d0\u4f9b\u3057\u307e\u3059\u3002<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">SPD\u306e\u76ee\u7684\u306f\u3001\u8ca0\u8377\u306b\u5230\u9054\u3059\u308b\u3059\u3079\u3066\u306e\u30b5\u30fc\u30b8\u3092\u300c\u906e\u65ad\u300d\u3059\u308b\u3053\u3068\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u306e\u4ee3\u308f\u308a\u3001\u96fb\u5727\u5236\u9650\u578bSPD\u306f\u4e0a\u6607\u3059\u308b\u904e\u6e21\u96fb\u5727\u306b\u5fdc\u7b54\u3057\u3001\u30b5\u30fc\u30b8\u96fb\u6d41\u3092\u5c0e\u901a\u3055\u305b\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u306e\u52d5\u4f5c\u306b\u3088\u308a\u3001\u4fdd\u8b77\u5bfe\u8c61\u56de\u8def\u306b\u304b\u304b\u308b\u96fb\u5727\u304c\u5236\u9650\u3055\u308c\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f8b\u3048\u3070\u3001\u7c21\u7565\u5316\u3057\u305fPV\u30b7\u30b9\u30c6\u30e0\u3067\u306f\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>PV\u30a2\u30ec\u30a4 \u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500 \u30a4\u30f3\u30d0\u30fc\u30bf\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u901a\u5e38\u904b\u8ee2\u6642\u3001PV\u96fb\u529b\u306f\u30a4\u30f3\u30d0\u30fc\u30bf\u306b\u5411\u304b\u3063\u3066\u6d41\u308c\u7d9a\u3051\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u30b5\u30fc\u30b8\u767a\u751f\u6642\u3001SPD\u306f\u4fdd\u8b77\u30e2\u30fc\u30c9\u306b\u5f93\u3063\u3066\u5c0e\u901a\u3057\u3001\u904e\u6e21\u96fb\u5727\u3092\u672c\u6765\u5230\u9054\u3059\u308b\u306f\u305a\u306e\u30ec\u30d9\u30eb\u3088\u308a\u3082\u4f4e\u304f\u6291\u3048\u308b\u5f79\u5272\u3092\u679c\u305f\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u304c\u3001SPD\u3092\u56de\u8def\u306b\u5bfe\u3057\u3066\u4e26\u5217\u306b\u914d\u7f6e\u3059\u308b\u57fa\u672c\u7684\u306a\u7406\u7531\u3067\u3059\u3002.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">4. SPD\u306f\u901a\u5e38\u3001\u4e3b\u96fb\u6e90\u7d4c\u8def\u306e\u4e00\u90e8\u3067\u306f\u3042\u308a\u307e\u305b\u3093<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e00\u822c\u7684\u306aSPD\u306f\u4e26\u5217\u5206\u5c90\u3068\u3057\u3066\u63a5\u7d9a\u3055\u308c\u308b\u305f\u3081\u3001\u96fb\u6e90\u3068\u8ca0\u8377\u306e\u9593\u306e\u901a\u5e38\u306e\u5c0e\u901a\u7d4c\u8def\u306b\u306f\u306a\u308a\u307e\u305b\u3093\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u306b\u306f\u5b9f\u7528\u4e0a\u306e\u91cd\u8981\u306a\u5229\u70b9\u304c\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The system&#8217;s normal operating current does not depend on continuously passing through the SPD protection elements.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3082\u3061\u308d\u3093\u3001\u3053\u308c\u306f\u8a2d\u7f6e\u5f8c\u306bSPD\u3092\u653e\u7f6e\u3057\u3066\u3088\u3044\u3068\u3044\u3046\u610f\u5473\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">SPD\u306f\u7570\u5e38\u306a\u96fb\u6c17\u7684\u30b9\u30c8\u30ec\u30b9\u3092\u53d7\u3051\u305f\u5f8c\u306b\u52a3\u5316\u307e\u305f\u306f\u5207\u65ad\u3055\u308c\u308b\u53ef\u80fd\u6027\u304c\u3042\u308b\u305f\u3081\u3001\u305d\u306e\u72b6\u614b\u8868\u793a\u306f\u5b9a\u671f\u7684\u306b\u78ba\u8a8d\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Why Isn&#8217;t a Typical SPD Connected in Series?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">SPD\u304c\u4e26\u5217\u306b\u63a5\u7d9a\u3055\u308c\u308b\u7406\u7531\u3092\u7406\u89e3\u3059\u308b\u3053\u3068\u306f\u3001\u4e00\u822c\u7684\u306a\u5206\u8def\u63a5\u7d9a\u578bSPD\u304c\u901a\u5e38\u306e\u8ca0\u8377\u7d4c\u8def\u306b\u5bfe\u3057\u3066\u76f4\u5217\u306b\u914d\u7f6e\u3055\u308c\u306a\u3044\u7406\u7531\u3092\u8aac\u660e\u3059\u308b\u52a9\u3051\u306b\u3082\u306a\u308b\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u914d\u7dda\u7528\u906e\u65ad\u5668\u3084\u30d2\u30e5\u30fc\u30ba\u306f\u3001\u56de\u8def\u96fb\u6d41\u3092\u6d41\u3059\u5fc5\u8981\u304c\u3042\u308b\u305f\u3081\u3001\u901a\u5e38\u306f\u76f4\u5217\u306b\u8a2d\u7f6e\u3055\u308c\u307e\u3059\u3002\u4e00\u822c\u7684\u306a\u4e26\u5217\u63a5\u7d9a\u578bSPD\u306f\u3001\u305d\u308c\u3068\u306f\u7570\u306a\u308b\u6a5f\u80fd\u306e\u305f\u3081\u306b\u8a2d\u8a08\u3055\u308c\u3066\u3044\u307e\u3059\u3002.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u901a\u5e38\u306e\u8ca0\u8377\u96fb\u6d41\u306f\u76f4\u5217\u30c7\u30d0\u30a4\u30b9\u3092\u901a\u904e\u3057\u306a\u3051\u308c\u3070\u306a\u3089\u306a\u3044<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u771f\u306e\u76f4\u5217\u63a5\u7d9a\u306f\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u306a\u308a\u307e\u3059\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\u96fb\u6e90 \u2192 \u30c7\u30d0\u30a4\u30b9 \u2192 \u8ca0\u8377\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">SPD\u30a2\u30bb\u30f3\u30d6\u30ea\u5168\u4f53\u3092\u8ca0\u8377\u7d4c\u8def\u306b\u633f\u5165\u3059\u308b\u5834\u5408\u3001SPD\u306f\u9023\u7d9a\u7684\u306a\u8ca0\u8377\u96fb\u6d41\u306b\u5bfe\u5fdc\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u306e\u5c0e\u4f53\u3001\u7aef\u5b50\u3001\u71b1\u8a2d\u8a08\u3001\u77ed\u7d61\u6027\u80fd\u3001\u304a\u3088\u3073\u6545\u969c\u6642\u306e\u6319\u52d5\u306f\u3059\u3079\u3066\u3001\u305d\u306e\u7528\u9014\u306b\u5408\u308f\u305b\u3066\u8a2d\u8a08\u3055\u308c\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e00\u822c\u7684\u306aDIN\u30ec\u30fc\u30eb\u53d6\u308a\u4ed8\u3051\u578b\u306e\u30bf\u30a4\u30d71\u307e\u305f\u306f\u30bf\u30a4\u30d72\u306e\u4e26\u5217\u63a5\u7d9a\u578bSPD\u306f\u3001\u901a\u5e38\u305d\u306e\u3088\u3046\u306a\u4f7f\u7528\u65b9\u6cd5\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">SPD\u306e\u30b5\u30fc\u30b8\u5b9a\u683c\u306f\u8ca0\u8377\u96fb\u6d41\u5b9a\u683c\u3067\u306f\u3042\u308a\u307e\u305b\u3093<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u306fSPD\u306e\u9298\u677f\u3092\u8aad\u307f\u89e3\u304f\u4e0a\u3067\u7279\u306b\u91cd\u8981\u306a\u30dd\u30a4\u30f3\u30c8\u3067\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f8b\u3048\u3070\u3001\u3042\u308bSPD\u306b\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u8a18\u8f09\u3055\u308c\u3066\u3044\u308b\u3068\u3057\u307e\u3059\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>In = 20 kA<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u3057\u3066<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Imax = 40 kA<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"683\" src=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-in-imax-vs-load-current-1024x683.jpg\" alt=\"SPD In and Imax surge current ratings compared with normal load current\" class=\"wp-image-4478\" srcset=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-in-imax-vs-load-current-1024x683.jpg 1024w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-in-imax-vs-load-current-300x200.jpg 300w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-in-imax-vs-load-current-768x512.jpg 768w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-in-imax-vs-load-current-18x12.jpg 18w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-in-imax-vs-load-current-600x400.jpg 600w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-in-imax-vs-load-current.jpg 1536w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">In\u304a\u3088\u3073Imax\u306f\u30b5\u30fc\u30b8\u653e\u96fb\u96fb\u6d41\u306e\u6027\u80fd\u3092\u793a\u3059\u3082\u306e\u3067\u3042\u308a\u3001\u4fdd\u8b77\u5bfe\u8c61\u56de\u8def\u306e\u901a\u5e38\u52d5\u4f5c\u96fb\u6d41\u3092\u793a\u3059\u3082\u306e\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u3089\u306eSPD\u5b9a\u683c\u306b\u3064\u3044\u3066\u307e\u3060\u4e0d\u660e\u306a\u70b9\u304c\u3042\u308b\u5834\u5408\u306f\u3001\u5f53\u793e\u306e <strong><a href=\"https:\/\/cnkuangya.com\/ja\/%e3%83%96%e3%83%ad%e3%82%b0\/dc-spd-specifications\/\">DC SPD\u4ed5\u69d8\u30ac\u30a4\u30c9\u3092\u3054\u53c2\u7167\u304f\u3060\u3055\u3044<\/a><\/strong> Ucpv\u3001In\u3001Imax\u3001Up\u304a\u3088\u3073Iscpv\u306b\u3064\u3044\u3066\u8a73\u7d30\u306b\u8aac\u660e\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u3089\u306e\u6570\u5024\u306f\u3001 <strong>\u306a\u3044<\/strong> SPD\u304c20 kA\u307e\u305f\u306f40 kA\u306e\u901a\u5e38\u8ca0\u8377\u96fb\u6d41\u3092\u7d99\u7d9a\u7684\u306b\u6d41\u3059\u3088\u3046\u306b\u8a2d\u8a08\u3055\u308c\u3066\u3044\u308b\u3053\u3068\u3092\u610f\u5473\u3059\u308b\u3082\u306e\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u30bf\u30a4\u30d72 SPD\u306b\u304a\u3044\u3066\u3001, <strong>\u3067<\/strong> \u306f8\/20 \u03bcs\u306e\u96fb\u6d41\u30a4\u30f3\u30d1\u30eb\u30b9\u306b\u95a2\u9023\u3059\u308b\u516c\u79f0\u653e\u96fb\u96fb\u6d41\u3092\u6307\u3057\u3001\u4e00\u65b9\u3067 <strong>\u30a2\u30a4\u30de\u30c3\u30af\u30b9<\/strong> \u306f8\/20 \u03bcs\u306e\u30a4\u30f3\u30d1\u30eb\u30b9\u306b\u95a2\u9023\u3059\u308b\u6700\u5927\u653e\u96fb\u96fb\u6d41\u3092\u6307\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Phoenix Contact&#8217;s technical definitions likewise describe In and Imax as impulse-current values flowing through the SPD, not normal continuous load-current ratings.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3057\u305f\u304c\u3063\u3066\uff1a<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>In\u304a\u3088\u3073Imax\u306f\u30b5\u30fc\u30b8\u653e\u96fb\u96fb\u6d41\u306e\u5b9a\u683c\u5024\u3067\u3042\u308a\u3001\u8ca0\u8377\u306e\u901a\u5e38\u52d5\u4f5c\u96fb\u6d41\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/strong><\/p>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u306e\u533a\u5225\u306f\u3001SPD\u3092\u9078\u5b9a\u307e\u305f\u306f\u8aac\u660e\u3059\u308b\u969b\u306b\u975e\u5e38\u306b\u91cd\u8981\u3067\u3059\u3002.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u3053\u308c\u306f\u76f4\u5217\u63a5\u7d9a\u578bSPD\u304c\u5b58\u5728\u3057\u306a\u3044\u3068\u3044\u3046\u610f\u5473\u3067\u3057\u3087\u3046\u304b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u3046\u3060\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u306f\u91cd\u8981\u306a\u4f8b\u5916\u3067\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u672c\u8a18\u4e8b\u3067\u53d6\u308a\u4e0a\u3052\u305f\u4e00\u822c\u7684\u306a\u30bf\u30a4\u30d71\u304a\u3088\u3073\u30bf\u30a4\u30d72\u306e\u96fb\u6e90\u7528SPD\u306f\u901a\u5e38\u4e26\u5217\u306b\u8a2d\u7f6e\u3055\u308c\u307e\u3059\u304c\u3001\u76f4\u5217\u63a5\u7d9a\u578b\u306eSPD\u30a2\u30bb\u30f3\u30d6\u30ea\u3084\u76f4\u5217\u63a5\u7d9a\u578b\u306e\u30b5\u30fc\u30b8\u30d5\u30a3\u30eb\u30bf\u3082\u5b58\u5728\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u30b7\u30e5\u30ca\u30a4\u30c0\u30fc\u30a8\u30ec\u30af\u30c8\u30ea\u30c3\u30af\u306f\u3001\u76f4\u5217\u63a5\u7d9a\u88fd\u54c1\u306f\u7279\u5b9a\u306e\u8ca0\u8377\u306e\u8fd1\u304f\u306b\u30a4\u30f3\u30e9\u30a4\u30f3\u3067\u8a2d\u7f6e\u3055\u308c\u308b\u306e\u304c\u4e00\u822c\u7684\u3067\u3042\u308b\u4e00\u65b9\u3001\u4e26\u5217\u63a5\u7d9aSPD\u306f\u914d\u96fb\u76e4\u3084\u5206\u96fb\u76e4\u306b\u304a\u3044\u3066\u3088\u308a\u4e00\u822c\u7684\u306a\u69cb\u6210\u3067\u3042\u308b\u3068\u6307\u6458\u3057\u3066\u3044\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A series-connected product has to be designed specifically to carry the circuit&#8217;s load current.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3057\u305f\u304c\u3063\u3066\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u8a00\u3046\u306e\u306f\u8aa4\u308a\u3067\u3059\uff1a<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>\u201cSPD\u3092\u76f4\u5217\u306b\u63a5\u7d9a\u3059\u308b\u3053\u3068\u306f\u6c7a\u3057\u3066\u3067\u304d\u307e\u305b\u3093\u3002\u201d<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3088\u308a\u6280\u8853\u7684\u306b\u6b63\u78ba\u306a\u8a18\u8ff0\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3067\u3059\u3002<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>\u4e00\u822c\u7684\u306a\u914d\u96fb\u7528\u30bf\u30a4\u30d71\u304a\u3088\u3073\u30bf\u30a4\u30d72\u306eSPD\u306f\u4e26\u5217\u63a5\u7d9a\u3055\u308c\u307e\u3059\u304c\u3001\u7279\u5b9a\u306e\u7528\u9014\u5411\u3051\u306b\u8a2d\u8a08\u3055\u308c\u305f\u76f4\u5217\u63a5\u7d9a\u578b\u306e\u30b5\u30fc\u30b8\u4fdd\u8b77\u88fd\u54c1\u3082\u5b58\u5728\u3057\u307e\u3059\u3002.<\/strong><\/p>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">For solar PV and general distribution-board applications, always follow the actual SPD manufacturer&#8217;s wiring diagram.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e26\u5217\u63a5\u7d9a\u3068\u76f4\u5217\u63a5\u7d9a\uff1a\u7c21\u5358\u306a\u6bd4\u8f03<\/h2>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">\u4e0b\u8868\u306f\u3001\u4e00\u822c\u7684\u306a <strong>\u4e26\u5217\u63a5\u7d9a\u3055\u308c\u305fSPD<\/strong> \u304c\u3001\u901a\u5e38\u306e\u8ca0\u8377\u96fb\u6d41\u7d4c\u8def\u306b\u76f4\u63a5\u8a2d\u7f6e\u3055\u308c\u308b\u30c7\u30d0\u30a4\u30b9\u3068\u3069\u306e\u3088\u3046\u306b\u7570\u306a\u308b\u304b\u3092\u793a\u3057\u3066\u3044\u307e\u3059\u3002.<\/p>\n<\/blockquote>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"683\" src=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/parallel-spd-vs-series-device-1024x683.jpg\" alt=\"Parallel SPD connection compared with a series-connected electrical device\" class=\"wp-image-4479\" srcset=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/parallel-spd-vs-series-device-1024x683.jpg 1024w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/parallel-spd-vs-series-device-300x200.jpg 300w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/parallel-spd-vs-series-device-768x512.jpg 768w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/parallel-spd-vs-series-device-18x12.jpg 18w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/parallel-spd-vs-series-device-600x400.jpg 600w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/parallel-spd-vs-series-device.jpg 1536w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">\u4e00\u822c\u7684\u306a\u4e26\u5217\u63a5\u7d9aSPD\u306f\u4fdd\u8b77\u5bfe\u8c61\u306e\u56de\u8def\u306b\u5bfe\u3057\u3066\u4e26\u5217\u306b\u63a5\u7d9a\u3055\u308c\u307e\u3059\u304c\u3001\u76f4\u5217\u63a5\u7d9a\u30c7\u30d0\u30a4\u30b9\u306f\u901a\u5e38\u306e\u96fb\u6d41\u7d4c\u8def\u306b\u76f4\u63a5\u914d\u7f6e\u3055\u308c\u307e\u3059\u3002.<\/figcaption><\/figure>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>\u7279\u5fb4<\/th><th>\u4e00\u822c\u7684\u306a\u4e26\u5217\u63a5\u7d9a\u578bSPD<\/th><th>\u76f4\u5217\u63a5\u7d9a\u578b\u30c7\u30d0\u30a4\u30b9<\/th><\/tr><\/thead><tbody><tr><td>\u901a\u5e38\u306e\u8ca0\u8377\u7d4c\u8def\u306b\u76f4\u63a5\u63a5\u7d9a<\/td><td>\u3044\u3044\u3048<\/td><td>\u306f\u3044<\/td><\/tr><tr><td>\u901a\u5e38\u306e\u8ca0\u8377\u96fb\u6d41\u304c\u30c7\u30d0\u30a4\u30b9\u5168\u4f53\u3092\u901a\u904e\u3059\u308b<\/td><td>\u3044\u3044\u3048<\/td><td>\u306f\u3044<\/td><\/tr><tr><td>Type 1 \/ Type 2 \u96fb\u6e90\u7528SPD\u306b\u304a\u3051\u308b\u4e00\u822c\u7684\u306a\u69cb\u6210<\/td><td>\u306f\u3044<\/td><td>\u3042\u307e\u308a\u4e00\u822c\u7684\u3067\u306f\u306a\u3044<\/td><\/tr><tr><td>\u4e3b\u306a\u76ee\u7684<\/td><td>\u30b5\u30fc\u30b8\u96fb\u6d41\u7d4c\u8def\u3092\u63d0\u4f9b\u3059\u308b\u3053\u3068\u3067\u904e\u6e21\u904e\u96fb\u5727\u3092\u5236\u9650\u3059\u308b<\/td><td>\u88fd\u54c1\u8a2d\u8a08\u306b\u4f9d\u5b58\u3059\u308b<\/td><\/tr><tr><td>\u30c7\u30d0\u30a4\u30b9\u5168\u4f53\u306b\u3068\u3063\u3066\u91cd\u8981\u306a\u5b9a\u683c\u9023\u7d9a\u96fb\u6d41<\/td><td>\u901a\u5e38\u3001\u30a4\u30f3\u30e9\u30a4\u30f3\u30c7\u30d0\u30a4\u30b9\u3068\u306f\u7570\u306a\u308b\u65b9\u6cd5<\/td><td>\u306f\u3044<\/td><\/tr><tr><td>\u8a2d\u7f6e\u30ea\u30fc\u30c9\u7dda\u306e\u9577\u3055\u306f\u4fdd\u8b77\u6027\u80fd\u306b\u5f71\u97ff\u3092\u4e0e\u3048\u308b<\/td><td>\u306f\u3044<\/td><td>\u5185\u90e8\u914d\u7f6e\u306b\u3088\u308a\u3001\u5916\u90e8\u4e26\u5217\u30ea\u30fc\u30c9\u7dda\u306e\u9577\u3055\u306b\u3088\u308b\u5f71\u97ff\u3092\u4f4e\u6e1b\u3067\u304d\u308b\u5834\u5408\u304c\u3042\u308b<\/td><\/tr><tr><td>\u4ee3\u8868\u7684\u306a\u7528\u9014<\/td><td>\u914d\u96fb\u76e4\u3001\u6a5f\u5668\u5165\u53e3\u3001\u592a\u967d\u5149\u767a\u96fb\u30b7\u30b9\u30c6\u30e0<\/td><td>\u7279\u5b9a\u306e\u611f\u5ea6\u306e\u9ad8\u3044\u8ca0\u8377\u3001\u307e\u305f\u306f\u7279\u6b8a\u306a\u4fdd\u8b77\u30fb\u30d5\u30a3\u30eb\u30bf\u30ea\u30f3\u30b0\u7528\u9014<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u91cd\u8981\u306a\u70b9\u306f\u3001\u3069\u3061\u3089\u304b\u4e00\u65b9\u306e\u65b9\u6cd5\u304c\u666e\u904d\u7684\u306b\u300c\u512a\u308c\u3066\u300d\u304a\u308a\u3001\u3082\u3046\u4e00\u65b9\u304c\u300c\u52a3\u3063\u3066\u300d\u3044\u308b\u3068\u3044\u3046\u3053\u3068\u3067\u306f\u306a\u3044\u201c<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u308c\u3089\u306f\u7570\u306a\u308b\u88fd\u54c1\u30a2\u30fc\u30ad\u30c6\u30af\u30c1\u30e3\u3067\u3042\u308b.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u305f\u3060\u3057\u3001\u4e00\u822c\u7684\u306aDIN\u30ec\u30fc\u30eb\u53d6\u308a\u4ed8\u3051\u578b\u96fb\u6e90\u7528SPD\u306e\u5834\u5408\u3001\u4e26\u5217\u63a5\u7d9a\u304c\u901a\u5e38\u60f3\u5b9a\u3055\u308c\u308b\u8a2d\u7f6e\u65b9\u6cd5\u3067\u3042\u308b.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u592a\u967d\u5149\u767a\u96fbDC\u30b7\u30b9\u30c6\u30e0\u306b\u304a\u3044\u3066\u3001SPD\u306f\u3069\u306e\u3088\u3046\u306b\u63a5\u7d9a\u3055\u308c\u308b\u304b\uff1f<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The same principle applies in many photovoltaic systems, where the SPD is connected in parallel with the DC circuit according to the manufacturer&#8217;s wiring configuration.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"683\" src=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/dc-spd-parallel-connection-solar-pv-system-1024x683.jpg\" alt=\"DC SPD connected in parallel in a solar PV system\" class=\"wp-image-4477\" srcset=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/dc-spd-parallel-connection-solar-pv-system-1024x683.jpg 1024w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/dc-spd-parallel-connection-solar-pv-system-300x200.jpg 300w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/dc-spd-parallel-connection-solar-pv-system-768x512.jpg 768w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/dc-spd-parallel-connection-solar-pv-system-18x12.jpg 18w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/dc-spd-parallel-connection-solar-pv-system-600x400.jpg 600w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/dc-spd-parallel-connection-solar-pv-system.jpg 1536w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">DC SPD\u306f\u901a\u5e38\u3001SPD\u306e\u69cb\u6210\u304a\u3088\u3073\u30e1\u30fc\u30ab\u30fc\u306e\u914d\u7dda\u56f3\u306b\u5f93\u3044\u3001PV\u56de\u8def\u3068\u4e26\u5217\u306b\u63a5\u7d9a\u3055\u308c\u307e\u3059\u3002.<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">\u305f\u3060\u3057\u3001DC SPD\u306e\u914d\u7dda\u306b\u306f\u7d30\u5fc3\u306e\u6ce8\u610f\u304c\u5fc5\u8981\u3067\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3059\u3079\u3066\u306ePV\u7528SPD\u304c\u5358\u7d14\u306b\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u914d\u7dda\u3055\u308c\u3066\u3044\u308b\u3068\u60f3\u5b9a\u3059\u308b\u306e\u306f\u8aa4\u308a\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>DC+ \u2192 SPD \u2192 PE\n<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u5b9f\u969b\u306e\u5185\u90e8\u4fdd\u8b77\u56de\u8def\u306f\u7570\u306a\u308b\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u88fd\u54c1\u304a\u3088\u3073PV\u30b7\u30b9\u30c6\u30e0\u306e\u69cb\u6210\u306b\u5fdc\u3058\u3066\u3001SPD\u306f\u4ee5\u4e0b\u306e\u9593\u3067\u306e\u4fdd\u8b77\u30e2\u30fc\u30c9\u3092\u63d0\u4f9b\u3059\u308b\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>DC+ \u3068 PE<\/li>\n\n\n\n<li>DC-\u304a\u3088\u3073PE<\/li>\n\n\n\n<li>DC+\u304a\u3088\u3073DC-<\/li>\n\n\n\n<li>\u3053\u308c\u3089\u306e\u7d4c\u8def\u306e\u7d44\u307f\u5408\u308f\u305b<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u63a5\u5730\u30b7\u30b9\u30c6\u30e0\u3084PV\u30a2\u30fc\u30ad\u30c6\u30af\u30c1\u30e3\u306e\u9055\u3044\u306b\u3088\u308a\u3001\u7570\u306a\u308bSPD\u56de\u8def\u69cb\u6210\u304c\u4f7f\u7528\u3055\u308c\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e26\u5217\u63a5\u7d9a\u3055\u308c\u308bPV\u7528SPD\u306e\u5834\u5408\u3001\u6b63\u78ba\u306a\u7aef\u5b50\u914d\u7f6e\u306fSPD\u306e\u8a2d\u8a08\u3001\u30b7\u30b9\u30c6\u30e0\u30c8\u30dd\u30ed\u30b8\u30fc\u3001\u304a\u3088\u3073\u30e1\u30fc\u30ab\u30fc\u306e\u914d\u7dda\u56f3\u306b\u4f9d\u5b58\u3057\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is why the wiring diagram printed on the SPD or provided in the manufacturer&#8217;s installation instructions is so important.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u592a\u967d\u5149\u767a\u96fbDC\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306b\u3064\u3044\u3066\u306f\u3001\u5c02\u7528\u306eIEC\u88fd\u54c1\u898f\u683c\u3068\u3057\u3066IEC 61643-31\u304c\u5b9a\u3081\u3089\u308c\u3066\u3044\u307e\u3059\u3002DEHN\u793e\u306f\u3001PV\u304a\u3088\u3073\u4f4e\u5727SPD\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u306b\u95a2\u9023\u3059\u308b\u8a2d\u7f6e\u898f\u683c\u3068\u3057\u3066\u3001IEC 60364-7-712\u304a\u3088\u3073IEC 60364-5-53\u3082\u6319\u3052\u3066\u3044\u307e\u3059\u3002.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">AC\u7528SPD\u306e\u914d\u7dda\u56f3\u3092DC\u7528SPD\u306b\u6d41\u7528\u3057\u306a\u3044\u3067\u304f\u3060\u3055\u3044<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">AC\u7528SPD\u3068DC\u7528SPD\u306f\u540c\u69d8\u306e\u30b5\u30fc\u30b8\u4fdd\u8b77\u539f\u7406\u306b\u57fa\u3065\u3044\u3066\u3044\u308b\u3082\u306e\u306e\u3001\u4e21\u30b7\u30b9\u30c6\u30e0\u306b\u4e92\u63db\u6027\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u76f4\u6d41\u306b\u306f\u81ea\u7136\u306a\u30bc\u30ed\u30af\u30ed\u30b9\u70b9\u304c\u5b58\u5728\u3057\u306a\u3044\u305f\u3081\u3001DC\u30a2\u30fc\u30af\u306e\u906e\u65ad\u304c\u3088\u308a\u56f0\u96e3\u3067\u3042\u308a\u3001DC\u30b7\u30b9\u30c6\u30e0\u306b\u306f\u7279\u6709\u306e\u8ab2\u984c\u304c\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u306e\u305f\u3081\u3001SPD\u306fDC\u96fb\u5727\u3001\u30b7\u30b9\u30c6\u30e0\u69cb\u6210\u3001\u304a\u3088\u3073\u7528\u9014\u306b\u9069\u5408\u3057\u305f\u5c02\u7528\u306e\u3082\u306e\u3092\u9078\u5b9a\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5e38\u306b\u4ee5\u4e0b\u306e\u9805\u76ee\u3092\u78ba\u8a8d\u3057\u3066\u304f\u3060\u3055\u3044\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u6700\u5927\u9023\u7d9a\u4f7f\u7528\u96fb\u5727<\/li>\n\n\n\n<li>DC\u6975\u6027\u304a\u3088\u3073\u7aef\u5b50\u8868\u793a<\/li>\n\n\n\n<li>SPD\u30bf\u30a4\u30d7<\/li>\n\n\n\n<li>\u4fdd\u8b77\u30e2\u30fc\u30c9<\/li>\n\n\n\n<li>\u63a5\u5730\u69cb\u6210<\/li>\n\n\n\n<li>\u77ed\u7d61\u8010\u91cf\u8981\u4ef6<\/li>\n\n\n\n<li>\u30e1\u30fc\u30ab\u30fc\u914d\u7dda\u56f3<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u8a2d\u7f6e\u524d\u3002.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4f8b\uff1aKUANGYA\u88fd\u30bf\u30a4\u30d72 DC SPD\u306e\u8aad\u307f\u65b9<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">KUANGYA\u88fdKYPV\/1000\u30bf\u30a4\u30d72 DC SPD\u3092\u4f8b\u306b\u6319\u3052\u308b\u3068\u3001\u9298\u677f\u306b\u306f\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u30d1\u30e9\u30e1\u30fc\u30bf\u304c\u8a18\u8f09\u3055\u308c\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Uc = 1000 V DC<\/strong><\/li>\n\n\n\n<li><strong>In = 20 kA<\/strong><\/li>\n\n\n\n<li><strong>Imax = 40 kA<\/strong><\/li>\n\n\n\n<li><strong>Up = 3.5 kV<\/strong><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">These values describe different parts of the SPD&#8217;s electrical performance.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u30a6\u30af<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Uc\u306f\u3001SPD\u306b\u898f\u5b9a\u3055\u308c\u305f\u6700\u5927\u9023\u7d9a\u4f7f\u7528\u96fb\u5727\u3067\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u9069\u5207\u306a\u5b9a\u683c\u96fb\u5727\u3092\u9078\u629e\u3059\u308b\u969b\u306b\u306f\u3001\u30b7\u30b9\u30c6\u30e0\u96fb\u5727\u304a\u3088\u3073\u60f3\u5b9a\u3055\u308c\u308b\u52d5\u4f5c\u6761\u4ef6\u3092\u8003\u616e\u3057\u306a\u3051\u308c\u3070\u306a\u3089\u306a\u3044\u3002.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u3067<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">In\u306f\u516c\u79f0\u653e\u96fb\u96fb\u6d41\u3067\u3042\u308b\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u30bf\u30a4\u30d72 SPD\u306e\u5834\u5408\u3001\u3053\u308c\u306f8\/20 \u03bcs\u306e\u30a4\u30f3\u30d1\u30eb\u30b9\u96fb\u6d41\u6ce2\u5f62\u306b\u95a2\u9023\u4ed8\u3051\u3089\u308c\u308b\u3002.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u30a2\u30a4\u30de\u30c3\u30af\u30b9<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Imax\u306fSPD\u306b\u5bfe\u3057\u3066\u898f\u5b9a\u3055\u308c\u305f\u6700\u5927\u653e\u96fb\u96fb\u6d41\u3067\u3042\u308a\u3001\u3053\u306e\u30bf\u30a4\u30d7\u306e\u30c7\u30d0\u30a4\u30b9\u306b\u304a\u3044\u3066\u30828\/20 \u03bcs\u306e\u6ce2\u5f62\u306b\u95a2\u9023\u4ed8\u3051\u3089\u308c\u308b\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Imax\u306fIn\u4ee5\u4e0a\u3067\u3042\u308b\u3002.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e0a\u3078<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Up\u306f\u96fb\u5727\u9632\u8b77\u30ec\u30d9\u30eb\u3067\u3042\u308b\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u306f\u3001\u898f\u5b9a\u3055\u308c\u305f\u8a66\u9a13\u6761\u4ef6\u4e0b\u306b\u304a\u3051\u308bSPD\u306e\u96fb\u5727\u5236\u9650\u6027\u80fd\u3092\u793a\u3059\u3082\u306e\u3067\u3042\u308b\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The key point for today&#8217;s topic is this:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>20 kA\u306eIn\u304a\u3088\u307340 kA\u306eImax\u306f\u3001\u901a\u5e38\u52d5\u4f5c\u6642\u306bSPD\u306b20 kA\u307e\u305f\u306f40 kA\u306e\u96fb\u6d41\u304c\u7d99\u7d9a\u7684\u306b\u6d41\u308c\u308b\u3053\u3068\u3092\u610f\u5473\u3059\u308b\u3082\u306e\u3067\u306f\u3042\u308a\u307e\u305b\u3093\u3002.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u3053\u308c\u3089\u306f\u904e\u6e21\u30b5\u30fc\u30b8\u96fb\u6d41\u306e\u30d1\u30e9\u30e1\u30fc\u30bf\u3067\u3059\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">That is another reason why comparing an SPD&#8217;s In or Imax directly with the load current of an inverter is incorrect.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Does Parallel Connection Mean Wire Length Does Not Matter?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u3046\u3060\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In fact, connection length is extremely important for a parallel-connected SPD.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A surge has a very fast current rise.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The connecting conductors therefore have inductance, and the rapidly changing surge current can create an additional voltage drop along those conductors.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">That additional voltage is effectively added to the voltage experienced by the protected equipment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">IEA PVPS\u306e <strong><a href=\"https:\/\/www.nemasurge.org\/correct-installation-of-hard-wired-surge-protective-device\/\" rel=\"noopener\">NEMA\u2019s guidance on hard-wired SPD installation<\/a><\/strong>, the size and length of the connecting leads can affect the performance of a parallel-connected SPD, and short, direct connections are preferred.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Phoenix Contact makes the same point: long connecting conductors can increase the effective voltage protection level seen in the installation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">So even if two installations use exactly the same SPD, their real-world protection performance may not be identical if one has much longer connection conductors.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-connection-lead-length-protection-1024x768.jpg\" alt=\"Short and long SPD connection leads compared for surge protection\" class=\"wp-image-4480\" srcset=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-connection-lead-length-protection-1024x768.jpg 1024w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-connection-lead-length-protection-300x225.jpg 300w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-connection-lead-length-protection-768x576.jpg 768w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-connection-lead-length-protection-16x12.jpg 16w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-connection-lead-length-protection-600x450.jpg 600w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-connection-lead-length-protection.jpg 1448w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Short and direct SPD connections generally reduce additional inductive voltage during fast surge-current events.<\/figcaption><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">Good Practice<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The SPD connection should generally be:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>As short as practical<\/li>\n\n\n\n<li>As direct as practical<\/li>\n\n\n\n<li>Free from unnecessary loops<\/li>\n\n\n\n<li>Free from unnecessary sharp routing<\/li>\n\n\n\n<li>Installed according to the manufacturer&#8217;s instructions<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">This is also why SPD location matters.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If you want to understand this issue in more detail, see our guide:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong><a href=\"https:\/\/cnkuangya.com\/ja\/%e3%83%96%e3%83%ad%e3%82%b0\/spd-distance-from-inverter\/\">SPD\u3068\u30a4\u30f3\u30d0\u30fc\u30bf\u9593\u306e\u8ddd\u96e2\u306f\u91cd\u8981\u3067\u3059\u304b\uff1f<\/a><\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Where Should an SPD Be Installed?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The exact position depends on the system being protected.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For example, an SPD may be installed:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>At a main distribution board<\/li>\n\n\n\n<li>At a sub-distribution board<\/li>\n\n\n\n<li>Near sensitive equipment<\/li>\n\n\n\n<li>At the DC input of a PV inverter<\/li>\n\n\n\n<li>Inside or near a PV combiner box<\/li>\n\n\n\n<li>On the AC side of an inverter<\/li>\n\n\n\n<li>At appropriate lightning protection zone boundaries<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">If your inverter already includes surge protection, do not assume that an additional external SPD is automatically unnecessary. See <strong><a href=\"https:\/\/cnkuangya.com\/ja\/%e3%83%96%e3%83%ad%e3%82%b0\/solar-inverter-built-in-spd\/\">\u592a\u967d\u5149\u767a\u96fb\u7528\u30a4\u30f3\u30d0\u30fc\u30bf\u306bDC SPD\u304c\u5185\u8535\u3055\u308c\u3066\u3044\u308b\u5834\u5408\u3001\u5916\u90e8SPD\u306f\u5fc5\u8981\u304b\uff1f<\/a><\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The objective is not simply to put \u201cone SPD somewhere in the system.\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The SPD should be positioned as part of a coordinated protection concept.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For PV systems in particular, cable length and the location of the inverter, modules and building entry points can affect whether additional SPDs are appropriate.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">IEA PVPS\u306e <strong><a href=\"https:\/\/www.dehn-international.com\/en\/solutions\/photovoltaics\/buildings\" rel=\"noopener\">DEHN\u2019s photovoltaic surge protection guidance<\/a><\/strong>, SPDs should be installed as close as possible to the equipment being protected, such as the inverter, on both the AC and DC sides.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The specific requirements should always be determined from the applicable installation standard, risk assessment and manufacturer instructions.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Does a Parallel-Connected SPD Need a Fuse or Circuit Breaker?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Sometimes yes, but not always in exactly the same way.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is another area where oversimplified advice can cause problems.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A parallel SPD may require an external:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u30d2\u30e5\u30fc\u30ba<\/li>\n\n\n\n<li>\u914d\u7dda\u7528\u906e\u65ad\u5668<\/li>\n\n\n\n<li>Backup overcurrent protective device<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">depending on the SPD design and installation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Other SPDs may include internal protective or disconnecting components.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The correct arrangement depends on factors such as:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Manufacturer requirements<\/li>\n\n\n\n<li>SPD design<\/li>\n\n\n\n<li>Maximum permitted backup fuse<\/li>\n\n\n\n<li>Available prospective short-circuit current<\/li>\n\n\n\n<li>\u30b7\u30b9\u30c6\u30e0\u96fb\u5727<\/li>\n\n\n\n<li>\u8a2d\u7f6e\u5834\u6240<\/li>\n\n\n\n<li>Applicable electrical standard<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"683\" src=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-backup-fuse-circuit-breaker-1024x683.jpg\" alt=\"SPD backup fuse and circuit breaker selection factors\" class=\"wp-image-4481\" srcset=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-backup-fuse-circuit-breaker-1024x683.jpg 1024w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-backup-fuse-circuit-breaker-300x200.jpg 300w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-backup-fuse-circuit-breaker-768x512.jpg 768w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-backup-fuse-circuit-breaker-18x12.jpg 18w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-backup-fuse-circuit-breaker-600x400.jpg 600w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/spd-backup-fuse-circuit-breaker.jpg 1536w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Backup protection requirements depend on the SPD design, system fault current and manufacturer instructions.<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">NEMA specifically advises installers to follow the manufacturer&#8217;s requirements regarding fuses, breakers and connection leads.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Therefore, do not assume:<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">\u201cEvery SPD needs exactly the same backup breaker.\u201d<\/p>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">And do not assume:<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">\u201cBecause the SPD is connected in parallel, no overcurrent protection is ever required.\u201d<\/p>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Both statements can be wrong.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Always check the SPD datasheet and installation instructions.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Why Short SPD Connections Matter So Much<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Imagine two identical SPDs.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Installation A<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The SPD is mounted very close to the protected equipment, with short and direct conductors.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Installation B<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The SPD is several meters away and connected through long conductors.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Although the SPD nameplate is identical, the effective protection at the equipment can be different.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This happens because the connecting conductors contribute additional inductive voltage during a fast surge.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">NEMA explains this relationship using:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>V = L \u00d7 di\/dt<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">where:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>V<\/strong> = inductive voltage<\/li>\n\n\n\n<li><strong>L<\/strong> = \u5c0e\u4f53\u30a4\u30f3\u30c0\u30af\u30bf\u30f3\u30b9<\/li>\n\n\n\n<li><strong>di\/dt<\/strong> = rate of change of current<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The faster the current changes and the more inductance there is in the connection, the greater the additional voltage can become.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">You do not need to calculate this formula for every normal installation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u5b9f\u8df5\u7684\u306a\u6559\u8a13\u306f\u3082\u3063\u3068\u5358\u7d14\u3067\u3059\uff1a<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>Keep SPD connections short and direct.<\/strong><\/p>\n<\/blockquote>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Common SPD Wiring Mistakes<\/h2>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"768\" src=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/common-spd-wiring-mistakes-1024x768.png\" alt=\"Common SPD wiring mistakes in surge protection installations\" class=\"wp-image-4482\" srcset=\"https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/common-spd-wiring-mistakes-1024x768.png 1024w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/common-spd-wiring-mistakes-300x225.png 300w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/common-spd-wiring-mistakes-768x576.png 768w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/common-spd-wiring-mistakes-16x12.png 16w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/common-spd-wiring-mistakes-600x450.png 600w, https:\/\/cnkuangya.com\/wp-content\/uploads\/2026\/09\/common-spd-wiring-mistakes.png 1448w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">Common SPD installation mistakes include long connection leads, incorrect voltage selection and ignoring manufacturer wiring requirements.<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Understanding why the SPD is connected in parallel also makes several common installation mistakes easier to recognize.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">1. Treating a Standard SPD Like a Series Device<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Do not simply place a normal parallel DIN-rail SPD in the main load path unless the manufacturer&#8217;s design specifically requires that configuration.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Follow the wiring diagram for the exact product.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">2. Using Excessively Long Connection Wires<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A good SPD with poor wiring may provide worse protection than expected.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Long leads increase inductive voltage during a surge.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Short and direct routing is generally preferred.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">3. Ignoring the Protection and Earthing Arrangement<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Do not assume every surge simply flows from one line terminal to earth.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The protection modes depend on the electrical network and SPD design.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Correct PE, bonding and circuit connections are essential where required by the product and installation design.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">4. Choosing the Wrong DC Voltage Rating<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">An SPD must be suitable for the voltage that can continuously appear at its terminals.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is particularly important in PV systems, where string open-circuit voltage changes with temperature.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Choosing an SPD only because it says \u201cDC SPD\u201d is not enough.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The voltage rating must match the actual PV system design.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For a step-by-step method, see our <strong><a href=\"https:\/\/cnkuangya.com\/ja\/%e3%83%96%e3%83%ad%e3%82%b0\/dc-spd-selection-guide\/\">DC SPD voltage selection guide for solar PV systems<\/a><\/strong>.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">5. Confusing In and Imax With Load Current<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">This is one of the most common misunderstandings.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">An SPD marked:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>In = 20 kA<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">does not mean:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Normal load current = 20 kA<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In and Imax describe surge-current performance under specified impulse conditions.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">They are not normal operating-current ratings.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">6. Ignoring the Manufacturer&#8217;s Backup Protection Requirements<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Do not guess the fuse or breaker size.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Different SPD designs can have different backup protection requirements.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Some products also include integrated protective components.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Check the actual product documentation.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">7. Installing an SPD but Never Checking It Again<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Many modular SPDs include a visual status indicator.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If the indicator shows a fault or replacement condition, the protection module may need to be replaced.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Some SPDs also have remote signaling contacts for connection to alarms, PLCs or monitoring systems.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Installing the SPD is only the first step.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Its condition should also be checked during maintenance.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For common warning signs and replacement indicators, see <strong><a href=\"https:\/\/cnkuangya.com\/ja\/%e3%83%96%e3%83%ad%e3%82%b0\/how-to-know-if-an-spd-is-bad\/\">How to Know If an SPD Is Bad?<\/a><\/strong><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Parallel SPD vs. Circuit Breaker: What Is the Difference?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A circuit breaker and an SPD protect against different electrical problems.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u30b5\u30fc\u30ad\u30c3\u30c8\u30d6\u30ec\u30fc\u30ab\u30fc<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A circuit breaker is mainly intended to interrupt abnormal current conditions such as overloads or short circuits.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Because it must sense and interrupt circuit current, it is connected in series with the load.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">SPD<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">An SPD is intended to limit transient overvoltage.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A typical power SPD is connected in parallel so that it can conduct surge current when the transient voltage rises.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">That means:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Circuit breaker \u2192 current protection<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>SPD \u2192 transient overvoltage protection<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">One cannot normally replace the other.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">They perform different jobs.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Parallel SPD vs. Fuse: What Is the Difference?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The same principle applies to a fuse.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A fuse is installed in series with the circuit it protects.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Normal load current passes through the fuse element.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If excessive current persists, the fuse element opens the circuit.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A typical SPD behaves differently.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">It remains connected across the protected circuit and responds mainly when the voltage reaches a level that causes its protective elements to conduct.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">So although fuses, breakers and SPDs may all appear in the same electrical panel, their functions and connection methods are not the same.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u3088\u304f\u3042\u308b\u8cea\u554f<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">Is an SPD Connected in Series or Parallel?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Most common Type 1 and Type 2 power SPDs used in distribution boards and similar applications are connected in parallel with the circuit they protect.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">However, specially designed series-connected SPDs and surge filters also exist.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Always follow the wiring instructions for the exact product.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Why Are Type 1 and Type 2 SPDs Usually Connected in Parallel?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A typical SPD is connected in parallel because it does not need to carry the normal load current.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">During normal voltage conditions, it remains in a high-impedance state.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When a transient overvoltage occurs, it conducts surge current through its protection path and limits the voltage across the protected equipment.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Does Current Normally Flow Through an SPD?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The normal load current does not normally flow through a typical parallel-connected SPD.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">However, a small leakage or operating current may exist depending on the SPD technology and design.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Therefore, saying \u201cabsolutely no current flows through an SPD\u201d would not be technically precise.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Does an SPD Send All Surge Current to Ground?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5fc5\u305a\u3057\u3082\u305d\u3046\u3067\u306f\u306a\u3044\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">An SPD may operate between line and neutral, line and earth, neutral and earth, line and line, or different DC conductors depending on its protection modes.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The exact surge-current path depends on the SPD and electrical system configuration.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Can an SPD Be Connected Directly Across the Supply?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Many power SPDs are designed to be connected in parallel across the appropriate conductors of the supply.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">However, the exact wiring arrangement depends on the SPD type, system earthing arrangement, required overcurrent protection and manufacturer instructions.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Never determine the connection from a generic diagram alone.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Why Isn&#8217;t a Typical SPD Installed in Series With the Load?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A normal parallel SPD is not designed to serve as the continuous main load-current path.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Installing an inline device requires a product specifically designed for that purpose, including suitable current, terminal, fault and thermal ratings.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Are In and Imax the Current of the Solar System?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u3046\u3060\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In and Imax are surge-discharge current parameters.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">They should not be confused with PV string operating current, short-circuit current or inverter input current.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Is a DC SPD Connected Differently From an AC SPD?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The general surge-protection principle is similar, but DC and AC systems have important differences.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The voltage rating, polarity, protection modes, earthing arrangement and internal SPD design may differ.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For PV systems, always use an SPD intended for the specific DC application and follow its wiring diagram.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Does an SPD Need a Ground Connection?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">It depends on the protection mode and system design.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Many power SPDs include protection paths involving PE, but not every surge protection mode is simply conductor-to-earth.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Use the manufacturer&#8217;s circuit diagram and the applicable earthing and bonding requirements.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Does SPD Wire Length Affect Protection?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u305d\u3046\u3060\u3002.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Long SPD connection conductors add inductance and can increase the voltage experienced by the protected equipment during a fast transient.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For this reason, connection conductors should generally be kept as short and direct as practical.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u8981\u70b9<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">If you only remember a few things from this article, remember these:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Most common Type 1 and Type 2 power SPDs are connected in parallel.<\/strong><\/li>\n\n\n\n<li><strong>A parallel-connected SPD does not normally carry the equipment&#8217;s normal load current.<\/strong><\/li>\n\n\n\n<li><strong>During a surge, the SPD conducts surge current through its designed protection path and limits the transient voltage.<\/strong><\/li>\n\n\n\n<li><strong>In and Imax are surge-discharge current ratings, not normal load-current ratings.<\/strong><\/li>\n\n\n\n<li><strong>Not every surge current path is simply \u201cto ground.\u201d The actual path depends on the SPD protection modes and system configuration.<\/strong><\/li>\n\n\n\n<li><strong>Series-connected surge protection products do exist, so \u201cSPDs can never be connected in series\u201d is technically incorrect.<\/strong><\/li>\n\n\n\n<li><strong>Short and direct SPD connections are important because conductor inductance can increase the effective voltage seen by the protected equipment.<\/strong><\/li>\n\n\n\n<li><strong>For PV DC systems, always follow the SPD wiring diagram, voltage rating, system earthing arrangement and manufacturer requirements.<\/strong><\/li>\n<\/ol>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u7d50\u8ad6<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">So, why is an SPD connected in parallel instead of series?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For a typical Type 1 or Type 2 <strong>\u4e26\u5217\u63a5\u7d9a\u3055\u308c\u305fSPD<\/strong>, the normal load current does not pass through the SPD as it would through a series-connected device.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Under normal operating conditions, the SPD remains largely in standby.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When a surge occurs, it conducts through its designed protection path and helps limit the voltage appearing across the protected equipment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">That is fundamentally different from a fuse or circuit breaker, which normally carries the circuit current and is therefore installed in series.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">However, correct SPD installation involves more than simply choosing \u201cparallel.\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The SPD voltage rating, protection modes, location, conductor length, earthing and bonding arrangement, backup protection and manufacturer wiring diagram all affect the final protection performance.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For solar PV systems in particular, always use an SPD designed for the relevant DC application and verify the actual system voltage and wiring configuration before installation.<\/p>","protected":false},"excerpt":{"rendered":"<p>If you look at a typical surge protective device (SPD) installation, you may notice something different from a fuse or circuit breaker. A fuse or circuit breaker is normally installed in series with the circuit, so the load current passes through it. A typical power SPD is usually connected in parallel with the circuit it protects, which is why many installers ask why an SPD is connected in parallel instead of series. Why? The simple answer is that a parallel-connected SPD does not need to carry the normal load current. Under normal operating conditions, it remains in a high-impedance state. When a transient overvoltage occurs, the SPD begins conducting and [&hellip;]<\/p>\n","protected":false},"author":7,"featured_media":4475,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35],"tags":[],"class_list":["post-4474","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/cnkuangya.com\/ja\/wp-json\/wp\/v2\/posts\/4474","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cnkuangya.com\/ja\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cnkuangya.com\/ja\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cnkuangya.com\/ja\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/cnkuangya.com\/ja\/wp-json\/wp\/v2\/comments?post=4474"}],"version-history":[{"count":2,"href":"https:\/\/cnkuangya.com\/ja\/wp-json\/wp\/v2\/posts\/4474\/revisions"}],"predecessor-version":[{"id":4486,"href":"https:\/\/cnkuangya.com\/ja\/wp-json\/wp\/v2\/posts\/4474\/revisions\/4486"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cnkuangya.com\/ja\/wp-json\/wp\/v2\/media\/4475"}],"wp:attachment":[{"href":"https:\/\/cnkuangya.com\/ja\/wp-json\/wp\/v2\/media?parent=4474"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cnkuangya.com\/ja\/wp-json\/wp\/v2\/categories?post=4474"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cnkuangya.com\/ja\/wp-json\/wp\/v2\/tags?post=4474"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}