{"id":3843,"date":"2026-08-19T16:01:17","date_gmt":"2026-08-19T16:01:17","guid":{"rendered":"https:\/\/huyuglobal.com\/?p=3843"},"modified":"2026-08-19T16:01:18","modified_gmt":"2026-08-19T16:01:18","slug":"wire-size-for-100-amp-service","status":"publish","type":"post","link":"https:\/\/huyuglobal.com\/vi\/blog\/wire-size-for-100-amp-service\/","title":{"rendered":"K\u00edch th\u01b0\u1edbc d\u00e2y cho d\u1ecbch v\u1ee5 100 Amp"},"content":{"rendered":"<p>Cho d\u00f9 b\u1ea1n \u0111ang n\u00e2ng c\u1ea5p d\u1ecbch v\u1ee5 nh\u00e0 \u1edf c\u0169 t\u1eeb 60A l\u00ean 100A, l\u1eafp \u0111\u1eb7t \u0111\u01b0\u1eddng c\u1ea5p ngu\u1ed3n cho gara t\u00e1ch r\u1eddi, ho\u1eb7c \u0111i d\u00e2y cho m\u1ed9t x\u01b0\u1edfng m\u1edbi, c\u00e2u h\u1ecfi \u0111\u1ea7u ti\u00ean lu\u00f4n gi\u1ed1ng nhau \u2014 lo\u1ea1i d\u00e2y n\u00e0o (\u0111\u1ed3ng hay nh\u00f4m) t\u00f4i c\u1ea7n cho d\u1ecbch v\u1ee5 100 amp? C\u00e2u tr\u1ea3 l\u1eddi d\u1ef1a tr\u00ean hai b\u1ed9 quy chu\u1ea9n kh\u00e1c nhau \u00e1p d\u1ee5ng, v\u00ec d\u1ecbch v\u1ee5 nh\u00e0 \u1edf c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng NEC 310.12 v\u00e0 do \u0111\u00f3 y\u00eau c\u1ea7u ampacity 83% (4 AWG \u0111\u1ed3ng ho\u1eb7c 2 AWG nh\u00f4m), trong khi d\u1ecbch v\u1ee5 th\u01b0\u01a1ng m\u1ea1i c\u00f3 ngh\u0129a l\u00e0 b\u1ea1n c\u1ea7n 3 AWG \u0111\u1ed3ng (\u0111\u1ec3 \u0111\u1ea3m b\u1ea3o ampacity \u0111\u1ea7y \u0111\u1ee7) ho\u1eb7c 1 AWG nh\u00f4m. L\u00e0m \u0111\u00fang b\u1ea1n s\u1ebd v\u01b0\u1ee3t qua ki\u1ec3m tra; l\u00e0m sai b\u1ea1n s\u1ebd b\u1ecb tr\u01b0\u1ee3t ki\u1ec3m tra ho\u1eb7c l\u00e0m qu\u00e1 nhi\u1ec7t d\u00e2y quan tr\u1ecdng nh\u1ea5t t\u1ea1i c\u00f4ng tr\u01b0\u1eddng x\u00e2y d\u1ef1ng c\u1ee7a b\u1ea1n. H\u01b0\u1edbng d\u1eabn sau s\u1ebd cung c\u1ea5p cho b\u1ea1n t\u1ea5t c\u1ea3 c\u00e1c k\u00edch th\u01b0\u1edbc d\u00e2y c\u1ea7n thi\u1ebft, c\u00e1c quy chu\u1ea9n li\u00ean quan, c\u00e1c ph\u00e9p t\u00ednh kh\u00e1c nhau li\u00ean quan \u0111\u1ebfn d\u00e2y \u0111\u1ed3ng v\u00e0 nh\u00f4m, v\u00e0 chi ti\u1ebft v\u1ec1 quy tr\u00ecnh l\u1eafp \u0111\u1eb7t.<\/p>\n<blockquote><p>T\u00f3m l\u1ea1i: Theo NEC 310.12 (quy t\u1eafc 83%), \u0111\u1ed1i v\u1edbi d\u1ecbch v\u1ee5 nh\u00e0 \u1edf 100A m\u1ed9t pha 120\/240V, k\u00edch th\u01b0\u1edbc t\u1ed1i thi\u1ec3u cho \u0111\u1ed3ng l\u00e0 4 AWG v\u00e0 cho nh\u00f4m l\u00e0 2 AWG. \u0110\u1ed1i v\u1edbi s\u1eed d\u1ee5ng th\u01b0\u01a1ng m\u1ea1i, d\u1ecbch v\u1ee5 ba pha, ho\u1eb7c feeder b\u1ea3ng ph\u1ee5 100A, c\u00e1c y\u00eau c\u1ea7u c\u1ee7a to\u00e0n b\u1ed9 NEC 310.16 \u00e1p d\u1ee5ng cho ampacity: k\u00edch th\u01b0\u1edbc t\u1ed1i thi\u1ec3u cho \u0111\u1ed3ng l\u00e0 3 AWG v\u00e0 cho nh\u00f4m l\u00e0 1 AWG. 2 AWG \u0111\u1ed3ng (115A) c\u0169ng c\u00f3 th\u1ec3 ph\u00f9 h\u1ee3p cho nhi\u1ec1u m\u1ea1ch 100A theo NEC 240.4(B). 6 AWG kh\u00f4ng \u0111\u00e1p \u1ee9ng y\u00eau c\u1ea7u v\u00ec n\u00f3 th\u1ea5p h\u01a1n (65A \u1edf 75 \u00b0C). \u0110i\u1ec1u ch\u1ec9nh k\u00edch th\u01b0\u1edbc theo gi\u00e1 tr\u1ecb trong c\u1ed9t 75 \u00b0C, t\u0103ng k\u00edch th\u01b0\u1edbc cho kho\u1ea3ng c\u00e1ch d\u00e0i h\u01a1n ~100-150 ft, v\u00e0 ki\u1ec3m tra l\u1ea1i v\u1edbi c\u1ea3 thanh tra \u0111\u1ecba ph\u01b0\u01a1ng v\u00e0 c\u00e1c ti\u1ec7n \u00edch \u0111\u1ecba ph\u01b0\u01a1ng trong d\u1ef1 \u00e1n c\u1ee7a b\u1ea1n.<\/p><\/blockquote>\n<p style=\"text-align: center;\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-3845\" src=\"https:\/\/huyuglobal.com\/wp-content\/uploads\/2026\/08\/The-Direct-Answer-Wire-Size-for-100A-Service.webp\" alt=\"C\u00e2u tr\u1ea3 l\u1eddi tr\u1ef1c ti\u1ebfp: K\u00edch th\u01b0\u1edbc d\u00e2y cho d\u1ecbch v\u1ee5 100A\" width=\"1448\" height=\"1086\" \/><\/p>\n<h2>C\u00e2u tr\u1ea3 l\u1eddi tr\u1ef1c ti\u1ebfp: K\u00edch th\u01b0\u1edbc d\u00e2y cho d\u1ecbch v\u1ee5 100A<\/h2>\n<p>\u0110\u00e2y l\u00e0 c\u00e2u tr\u1ea3 l\u1eddi \u0111\u1ea7y \u0111\u1ee7 trong m\u1ed9t b\u1ea3ng duy nh\u1ea5t. H\u00e0ng b\u1ea1n c\u1ea7n ph\u1ee5 thu\u1ed9c v\u00e0o lo\u1ea1i c\u1ea5u tr\u00fac v\u00e0 \u0111\u00e2y l\u00e0 c\u1eeda d\u1ecbch v\u1ee5 hay feeder.<\/p>\n<table>\n<thead>\n<tr>\n<th>K\u1ecbch b\u1ea3n<\/th>\n<th>\u0110\u1ed3ng<\/th>\n<th>Nh\u00f4m<\/th>\n<th>C\u01a1 s\u1edf m\u00e3<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><strong>D\u1ecbch v\u1ee5 nh\u00e0 \u1edf d\u00e2n c\u01b0<\/strong> (\u0111\u01a1n pha 120\/240V, h\u1ea7u h\u1ebft c\u00e1c nh\u00e0)<\/td>\n<td><strong>4 AWG<\/strong><\/td>\n<td><strong>2 AWG<\/strong><\/td>\n<td>NEC 310.12 (quy t\u1eafc 83%)<\/td>\n<\/tr>\n<tr>\n<td><strong>D\u1ecbch v\u1ee5 th\u01b0\u01a1ng m\u1ea1i \/ c\u00f4ng nghi\u1ec7p<\/strong> (\u0111\u01a1n pha ho\u1eb7c ba pha)<\/td>\n<td><strong>3 AWG<\/strong><\/td>\n<td><strong>1 AWG<\/strong><\/td>\n<td>NEC 310.16 (\u0111\u1ea7y \u0111\u1ee7 c\u00f4ng su\u1ea5t)<\/td>\n<\/tr>\n<tr>\n<td><strong>Feeder b\u1ea3ng ph\u1ee5 100A<\/strong> (gara, x\u01b0\u1edfng, ADU)<\/td>\n<td><strong>3 AWG<\/strong><\/td>\n<td><strong>1 AWG<\/strong><\/td>\n<td>NEC 310.16 (kh\u00f4ng ngo\u1ea1i l\u1ec7 nh\u00e0 \u1edf)<\/td>\n<\/tr>\n<tr>\n<td><strong>D\u1ecbch v\u1ee5 ba pha 100A<\/strong> (b\u1ea5t k\u1ef3 lo\u1ea1i s\u1eed d\u1ee5ng n\u00e0o)<\/td>\n<td><strong>3 AWG<\/strong><\/td>\n<td><strong>1 AWG<\/strong><\/td>\n<td>NEC 310.16 (kh\u00f4ng ngo\u1ea1i l\u1ec7 nh\u00e0 \u1edf)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>D\u01b0\u1edbi \u0111\u00e2y l\u00e0 ba \u0111i\u1ec3m l\u00e0m r\u00f5 c\u1ea7n l\u01b0u \u00fd:<\/p>\n<ul>\n<li>6 AWG kh\u00f4ng ph\u00f9 h\u1ee3p \u0111\u1ec3 mang t\u1ea3i 100A v\u00ec \u0111\u1ed3ng 6 AWG ch\u1ec9 c\u00f3 th\u1ec3 mang 65A \u1edf nhi\u1ec7t \u0111\u1ed9 75 \u0111\u1ed9 C. Do \u0111\u00f3 n\u00f3 n\u00ean l\u00e0 m\u1ed9t ph\u1ea7n c\u1ee7a m\u1ea1ch 50-60A.<\/li>\n<li>D\u00e2y \u0111\u1ed3ng 3 AWG h\u1eefu \u00edch \u0111\u1ec3 mang ch\u00ednh x\u00e1c 100A \u1edf 75 \u0111\u1ed9 C.<\/li>\n<li>D\u00e2y \u0111\u1ed3ng 2 AWG c\u0169ng ph\u00f9 h\u1ee3p v\u00ec n\u00f3 c\u00f3 c\u00f4ng su\u1ea5t 115A \u1edf 75 \u0111\u1ed9, n\u00ean theo NEC 240.4(B) c\u00f3 th\u1ec3 \u0111i d\u00e2y cho m\u1ea1ch s\u1eed d\u1ee5ng c\u1ea7u dao 100A.<\/li>\n<\/ul>\n<h2>NEC 310.12 &amp; Quy t\u1eafc 83% (D\u1ecbch v\u1ee5 nh\u00e0 \u1edf)<\/h2>\n<p>NEC 310.12 cho ph\u00e9p d\u00e2y d\u1eabn d\u1ecbch v\u1ee5 v\u00e0 feeder to\u00e0n b\u1ed9 nh\u00e0 \u0111\u01b0\u1ee3c \u0111\u1ecbnh k\u00edch th\u01b0\u1edbc \u1edf 83% c\u1ee7a \u0111\u1ecbnh m\u1ee9c d\u1ecbch v\u1ee5 cho nh\u00e0 \u1edf m\u1ed9t gia \u0111\u00ecnh (ho\u1eb7c \u0111\u01a1n v\u1ecb nh\u00e0 \u1edf ri\u00eang bi\u1ec7t) \u0111\u01b0\u1ee3c c\u1ea5p ngu\u1ed3n b\u1edfi h\u1ec7 th\u1ed1ng m\u1ed9t pha 120\/240V. L\u00fd do \u0111\u1eb1ng sau quy t\u1eafc n\u00e0y l\u00e0 th\u1ef1c t\u1ebf r\u1eb1ng t\u1ea3i trong m\u1ed9t h\u1ed9 gia \u0111\u00ecnh l\u00e0 \u0111a d\u1ea1ng. Th\u1eadt v\u1eady, kh\u00f4ng th\u1ec3 t\u1ea5t c\u1ea3 c\u00e1c t\u1ea3i \u0111i\u1ec7n ho\u1ea1t \u0111\u1ed9ng c\u00f9ng l\u00fac. Do \u0111\u00f3, NEC cho ph\u00e9p s\u1eed d\u1ee5ng k\u00edch th\u01b0\u1edbc d\u00e2y nh\u1ecf h\u01a1n so v\u1edbi c\u00e1c b\u1ea3ng chung quy \u0111\u1ecbnh.<\/p>\n<p>Vi\u1ec7c t\u00ednh to\u00e1n cho 100A nh\u01b0 sau: 100 x 0.83 = 83A ampacity c\u1ea7n thi\u1ebft. \u0110\u1ec3 ki\u1ec3m tra ampacity, ch\u00fang ta c\u1ea7n t\u00ecm x\u1ebfp h\u1ea1ng nhi\u1ec7t \u0111\u1ed9 \u2012 n\u1ebfu ch\u00fang ta \u0111ang n\u00f3i v\u1ec1 75\u00b0C:<\/p>\n<ul>\n<li>4 AWG \u0111\u1ed3ng (85A) \u2192 c\u00f3 th\u1ec3 ch\u1ecbu \u0111\u01b0\u1ee3c 83A \u2192 \u0111\u00e2y l\u00e0 k\u00edch th\u01b0\u1edbc \u0111\u1ed3ng ti\u00eau chu\u1ea9n cho d\u1ecbch v\u1ee5 nh\u00e0 \u1edf 100A.<\/li>\n<li>2 AWG nh\u00f4m (90A) \u2192 c\u00f3 th\u1ec3 ch\u1ecbu \u0111\u01b0\u1ee3c 83A \u2192 \u0111\u00e2y l\u00e0 k\u00edch th\u01b0\u1edbc nh\u00f4m ti\u00eau chu\u1ea9n cho d\u1ecbch v\u1ee5 nh\u00e0 \u1edf 100A.<\/li>\n<\/ul>\n<p>\u0110\u00f3 l\u00e0 l\u00fd do t\u1ea1i sao ng\u01b0\u1eddi ta n\u00f3i \u201cd\u1ecbch v\u1ee5 100A t\u01b0\u01a1ng \u0111\u01b0\u01a1ng 4 AWG \u0111\u1ed3ng ho\u1eb7c 2 AWG nh\u00f4m\u201d \u2013 quy t\u1eafc n\u00e0y cho bi\u1ebft th\u1ef1c t\u1ebf r\u1eb1ng n\u00f3 nh\u1ecf h\u01a1n m\u1ed9t k\u00edch th\u01b0\u1edbc so v\u1edbi b\u1ea3ng chung. Tuy nhi\u00ean, n\u00f3 kh\u00f4ng \u00e1p d\u1ee5ng cho<\/p>\n<ul>\n<li>C\u00e1c t\u00f2a nh\u00e0 th\u01b0\u01a1ng m\u1ea1i, b\u00e1n l\u1ebb, v\u0103n ph\u00f2ng, kho h\u00e0ng ho\u1eb7c s\u1ea3n xu\u1ea5t.<\/li>\n<li>D\u1ecbch v\u1ee5 ba pha.<\/li>\n<li>D\u00e2y d\u1eabn c\u1ea5p cho c\u00e1c b\u1ea3ng ph\u1ee5 \u2012 ch\u00fang s\u1eed d\u1ee5ng ampacity \u0111\u1ea7y \u0111\u1ee7 theo 310.16 ngay c\u1ea3 khi s\u1eed d\u1ee5ng trong c\u00f9ng m\u1ed9t h\u1ed9 gia \u0111\u00ecnh.<\/li>\n<\/ul>\n<p style=\"text-align: center;\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-3846\" src=\"https:\/\/huyuglobal.com\/wp-content\/uploads\/2026\/08\/NEC-310.16-Full-Ampacity-for-Commercial-Sub-Panels.webp\" alt=\"NEC 310.16: D\u00f2ng \u0111i\u1ec7n \u0111\u1ecbnh m\u1ee9c \u0111\u1ea7y \u0111\u1ee7 cho b\u1ea3ng \u0111i\u1ec7n th\u01b0\u01a1ng m\u1ea1i &amp; ph\u1ee5\" width=\"1448\" height=\"1086\" \/><\/p>\n<h2>NEC 310.16: Ampacity \u0111\u1ea7y \u0111\u1ee7 cho th\u01b0\u01a1ng m\u1ea1i &amp; b\u1ea3ng ph\u1ee5<\/h2>\n<p>Khi ngo\u1ea1i l\u1ec7 cho nh\u00e0 \u1edf kh\u00f4ng \u00e1p d\u1ee5ng, k\u00edch th\u01b0\u1edbc theo <strong>NEC 310.16 \u1edf 75\u00b0C<\/strong> (ti\u00eau chu\u1ea9n cho \u0111\u1ea7u n\u1ed1i thi\u1ebft b\u1ecb d\u1ecbch v\u1ee5):<\/p>\n<table>\n<thead>\n<tr>\n<th>D\u00e2y d\u1eabn<\/th>\n<th>D\u00f2ng \u0111i\u1ec7n \u0111\u1ecbnh m\u1ee9c @ 75\u00b0C<\/th>\n<th>C\u00f3 ph\u00f9 h\u1ee3p cho 100A kh\u00f4ng?<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>6 AWG \u0111\u1ed3ng<\/td>\n<td>65 A<\/td>\n<td>Kh\u00f4ng (m\u1ea1ch 50-60A)<\/td>\n<\/tr>\n<tr>\n<td>4 AWG \u0111\u1ed3ng<\/td>\n<td>85 A<\/td>\n<td>Kh\u00f4ng theo 310.16 (ch\u1ec9 theo 310.12 cho nh\u00e0 \u1edf)<\/td>\n<\/tr>\n<tr>\n<td><strong>3 AWG \u0111\u1ed3ng<\/strong><\/td>\n<td>100 A<\/td>\n<td><strong>C\u00f3 \u2014 t\u1ed1i thi\u1ec3u<\/strong><\/td>\n<\/tr>\n<tr>\n<td>2 AWG \u0111\u1ed3ng<\/td>\n<td>115 A<\/td>\n<td>C\u00f3 (l\u1ef1a ch\u1ecdn ph\u1ed5 bi\u1ebfn \u0111\u1ec3 d\u1ef1 ph\u00f2ng)<\/td>\n<\/tr>\n<tr>\n<td>2 AWG nh\u00f4m<\/td>\n<td>90 A<\/td>\n<td>Kh\u00f4ng theo 310.16 (ch\u1ec9 theo 310.12)<\/td>\n<\/tr>\n<tr>\n<td>1 AWG nh\u00f4m<\/td>\n<td>100 A<\/td>\n<td><strong>C\u00f3 \u2014 t\u1ed1i thi\u1ec3u<\/strong><\/td>\n<\/tr>\n<tr>\n<td>1\/0 nh\u00f4m<\/td>\n<td>120 A<\/td>\n<td>C\u00f3 (d\u01b0 margin)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>K\u1ebft qu\u1ea3 ch\u00ednh: M\u1eb7c d\u00f9 4 AWG \u0111\u1ed3ng \u0111\u01b0\u1ee3c ch\u1ea5p nh\u1eadn cho d\u1ecbch v\u1ee5 nh\u00e0 \u1edf, n\u00f3 kh\u00f4ng ph\u00f9 h\u1ee3p cho b\u1ea3ng ph\u1ee5 gara ho\u1eb7c d\u00e2y m\u1ea1ch 100A th\u01b0\u01a1ng m\u1ea1i \u2014 d\u00e2y n\u00e0y c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c ph\u00ea duy\u1ec7t nh\u01b0ng kh\u00f4ng theo ph\u01b0\u01a1ng ph\u00e1p ti\u00eau chu\u1ea9n cho d\u00e2y d\u1eabn b\u1ea3ng ph\u1ee5. \u0110\u00e2y l\u00e0 ngu\u1ed3n g\u1ed1c c\u1ee7a h\u1ea7u h\u1ebft s\u1ef1 nh\u1ea7m l\u1eabn v\u00e0 \u0111\u00f3 l\u00e0 l\u00fd do ti\u00eau chu\u1ea9n cho d\u00e2y d\u1eabn b\u1ea3ng ph\u1ee5 b\u1eb1ng \u0111\u1ed3ng l\u00e0 3 AWG \u0111\u1ed3ng ho\u1eb7c 1 AWG nh\u00f4m.<\/p>\n<h2>\u0110\u1ed3ng vs Nh\u00f4m: S\u1ef1 kh\u00e1c bi\u1ec7t l\u00e0 g\u00ec<\/h2>\n<p>C\u1ea3 hai \u0111\u1ec1u tu\u00e2n th\u1ee7 m\u00e3; l\u1ef1a ch\u1ecdn d\u1ef1a tr\u00ean kinh t\u1ebf v\u00e0 k\u1ef7 lu\u1eadt l\u1eafp \u0111\u1eb7t:<\/p>\n<table>\n<thead>\n<tr>\n<th>Y\u1ebfu t\u1ed1<\/th>\n<th>\u0110\u1ed3ng<\/th>\n<th>Nh\u00f4m<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Chi ph\u00ed t\u01b0\u01a1ng \u0111\u1ed1i<\/td>\n<td>C\u01a1 b\u1ea3n (\u0111\u1eaft)<\/td>\n<td>Kho\u1ea3ng 40-60% nh\u1eb9 h\u01a1n \u1edf k\u00edch th\u01b0\u1edbc n\u00e0y<\/td>\n<\/tr>\n<tr>\n<td>K\u00edch th\u01b0\u1edbc c\u1ea7n cho 100A (310.16)<\/td>\n<td>3 AWG<\/td>\n<td>1 AWG (l\u1edbn h\u01a1n hai k\u00edch th\u01b0\u1edbc)<\/td>\n<\/tr>\n<tr>\n<td>Tr\u1ecdng l\u01b0\u1ee3ng<\/td>\n<td>N\u1eb7ng h\u01a1n<\/td>\n<td>Kho\u1ea3ng 1\/3 tr\u1ecdng l\u01b0\u1ee3ng \u2014 d\u1ec5 k\u00e9o h\u01a1n<\/td>\n<\/tr>\n<tr>\n<td>\u0110\u1ed9 d\u1eabn \u0111i\u1ec7n<\/td>\n<td>Cao h\u01a1n<\/td>\n<td>~61% c\u1ee7a \u0111\u1ed3ng<\/td>\n<\/tr>\n<tr>\n<td>Quy t\u1eafc k\u1ebft th\u00fac<\/td>\n<td>Ti\u00eau chu\u1ea9n<\/td>\n<td>H\u1ee3p ch\u1ea5t ch\u1ed1ng oxy h\u00f3a, \u0111\u1ea7u cos AL-rated, m\u00f4-men xo\u1eafn ch\u00ednh x\u00e1c \u2014 b\u1eaft bu\u1ed9c<\/td>\n<\/tr>\n<tr>\n<td>\u0102n m\u00f2n<\/td>\n<td>T\u1ed1i thi\u1ec3u<\/td>\n<td>Oxy h\u00f3a t\u1ea1i \u0111i\u1ec3m k\u1ebft th\u00fac n\u1ebfu kh\u00f4ng \u0111\u01b0\u1ee3c x\u1eed l\u00fd<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Nh\u00f4m l\u00e0 v\u1eadt li\u1ec7u ph\u1ed5 bi\u1ebfn nh\u1ea5t \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng cho c\u1ea3 \u0111\u1ea7u v\u00e0o d\u1ecbch v\u1ee5 100A c\u0169ng nh\u01b0 cho c\u00e1c d\u00e2y c\u1ea5p d\u00e0i. Vi\u1ec7c l\u1eafp \u0111\u1eb7t n\u00f3 c\u0169ng l\u00e0 ki\u1ebfn th\u1ee9c ph\u1ed5 bi\u1ebfn trong s\u1ed1 c\u00e1c c\u00f4ng nh\u00e2n \u0111i\u1ec7n \u0111\u01b0\u1ee3c ch\u1ee9ng nh\u1eadn. C\u00f3 ba y\u1ebfu t\u1ed1 thi\u1ebft y\u1ebfu ph\u1ea3i \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong t\u1ea5t c\u1ea3 c\u00e1c l\u1eafp \u0111\u1eb7t nh\u00f4m: h\u1ee3p ch\u1ea5t k\u1ebft n\u1ed1i ch\u1ed1ng oxy h\u00f3a, \u0111\u1ea7u cos c\u00f3 \u0111\u00e1nh gi\u00e1 AL\/CU, v\u00e0 c\u1edd l\u00ea m\u00f4-men xo\u1eafn theo khuy\u1ebfn ngh\u1ecb c\u1ee7a nh\u00e0 s\u1ea3n xu\u1ea5t.<\/p>\n<h2>\u201cD\u00e2y 2-2-2-4\u201d c\u00f3 ngh\u0129a l\u00e0 g\u00ec?<\/h2>\n<p>N\u1ebfu b\u1ea1n ch\u1ecdn d\u00e2y c\u1ea5p 100A cho nh\u00e0 \u1edf, c\u00e1p \u0111\u01b0\u1ee3c ghi l\u00e0 \u201c2-2-2-4\u201d (c\u00f3 th\u1ec3 xu\u1ea5t hi\u1ec7n d\u01b0\u1edbi d\u1ea1ng \u201c2-2-2-4 SER\u201d ho\u1eb7c \u201c2-2-2-4 AL\u201d). K\u00fd hi\u1ec7u n\u00e0y ph\u00e2n t\u00edch c\u00e1c d\u00e2y d\u1eabn b\u00ean trong: 2 d\u00e2y d\u1eabn 2 AWG l\u00e0 hai pha n\u00f3ng, v\u00e0 m\u1ed9t d\u00e2y d\u1eabn trung t\u00ednh lo\u1ea1i 4 AWG c\u00f9ng v\u1edbi m\u1ed9t d\u00e2y d\u1eabn 4 AWG cho m\u1ee5c \u0111\u00edch n\u1ed1i \u0111\u1ea5t.<\/p>\n<ul>\n<li>Hai d\u00e2y n\u00f3ng 2 AWG + d\u00e2y trung t\u00ednh 2 AWG cung c\u1ea5p m\u1ea1ch 120\/240 volt.<\/li>\n<li>4 AWG l\u00e0 d\u00e2y n\u1ed1i \u0111\u1ea5t cho thi\u1ebft b\u1ecb.<\/li>\n<li>V\u00ec \u0111\u00e2y l\u00e0 lo\u1ea1i c\u00e1p SER nh\u00f4m, n\u00f3 \u0111\u00e1p \u1ee9ng y\u00eau c\u1ea7u ti\u00eau chu\u1ea9n 100A cho l\u1eafp \u0111\u1eb7t \u0111i\u1ec7n d\u00e2n d\u1ee5ng theo NEC 310.12 (2 AWG = 90A, \u0111\u1ee7 \u0111i\u1ec7n \u00e1p \u0111\u1ea7u ra 83A).<\/li>\n<\/ul>\n<p>\u0110\u1ed1i v\u1edbi c\u00e2u h\u1ecfi, \u201cd\u00e2y 2-2-2-4 c\u00f3 \u0111\u1ee7 cho 100 ampe kh\u00f4ng?\u201d c\u00e2u tr\u1ea3 l\u1eddi l\u00e0 \u201cc\u00f3\u201d cho d\u1ecbch v\u1ee5 d\u00e2n d\u1ee5ng v\u00e0 d\u00e2y c\u1ea5p 100A, n\u01a1i \u00e1p d\u1ee5ng quy \u0111\u1ecbnh 83%. Tuy nhi\u00ean, n\u00f3 kh\u00f4ng ph\u00f9 h\u1ee3p cho d\u1ecbch v\u1ee5 th\u01b0\u01a1ng m\u1ea1i 100A, n\u01a1i c\u1ea7n d\u00e2y 1 AWG cho c\u00e1c pha n\u00f3ng.<\/p>\n<h2>D\u00e2y 6 Gauge c\u00f3 ch\u1ecbu \u0111\u01b0\u1ee3c 100 Ampe kh\u00f4ng?<\/h2>\n<p>D\u00e2y \u0111\u1ed3ng 6 AWG ph\u00f9 h\u1ee3p cho c\u00f4ng vi\u1ec7c 65A \u1edf 75\u00b0C (55A \u1edf 60\u00b0C) nh\u01b0ng kh\u00f4ng \u0111\u1ee7 cho d\u1ecbch v\u1ee5 100A v\u00ec d\u00e2y n\u00e0y qu\u00e1 nhi\u1ec7t c\u00f3 th\u1ec3 l\u00e0m h\u1ecfng l\u1edbp c\u00e1ch \u0111i\u1ec7n v\u00e0 g\u00e2y nguy c\u01a1 ch\u00e1y nghi\u00eam tr\u1ecdng. N\u00ean s\u1eed d\u1ee5ng d\u00e2y n\u00e0y cho m\u1ea1ch d\u00f2ng th\u1ea5p, l\u00ean \u0111\u1ebfn 50-60A. \u0110\u1ed1i v\u1edbi c\u00f4ng vi\u1ec7c c\u00f3 t\u1ea3i 100A ho\u1eb7c h\u01a1n, ph\u1ea3i s\u1eed d\u1ee5ng d\u00e2y \u0111\u1ed3ng 3 AWG ho\u1eb7c nh\u00f4m 1 AWG.<\/p>\n<h2>D\u00e2y \u0111\u1ed3ng #3 c\u00f3 ph\u00f9 h\u1ee3p cho 100 Ampe kh\u00f4ng?<\/h2>\n<p>\u0110\u00fang v\u1eady. D\u00e2y \u0111\u1ed3ng 3 AWG \u0111\u01b0\u1ee3c \u0111\u00e1nh gi\u00e1 cho 100A \u1edf 75\u00b0C; \u0111\u00e2y l\u00e0 m\u1ee9c t\u1ed1i thi\u1ec3u ch\u00ednh x\u00e1c cho m\u1ea1ch t\u1ed5ng 100A, d\u1ecbch v\u1ee5 th\u01b0\u01a1ng m\u1ea1i ho\u1eb7c d\u00e2y c\u1ea5p ph\u1ee5 theo NEC 310.16. Nhi\u1ec1u th\u1ee3 \u0111i\u1ec7n ch\u1ecdn d\u00e2y \u0111\u1ed3ng 2 AWG (115A) \u0111\u1ec3 c\u00f3 d\u01b0 \u0111\u1ecba, gi\u1ea3m t\u1ea3i ho\u1eb7c ch\u1ea1y d\u00e2y d\u00e0i; \u0111i\u1ec1u n\u00e0y ho\u00e0n to\u00e0n ch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c. Ch\u1ec9 v\u1edbi d\u1ecbch v\u1ee5 d\u00e2n d\u1ee5ng, d\u00e2y \u0111\u1ed3ng 4 AWG l\u00e0 \u0111\u1ee7. T\u00f3m l\u1ea1i, khi h\u1ecfi d\u00e2y \u0111\u1ed3ng #3 c\u00f3 ph\u00f9 h\u1ee3p cho 100 ampe kh\u00f4ng; d\u00e2y n\u00e0y th\u1ef1c s\u1ef1 \u0111\u01b0\u1ee3c \u0111\u00e1nh gi\u00e1 \u0111\u00fang.<\/p>\n<h2 id=\"run-length\">Chi\u1ec1u d\u00e0i ch\u1ea1y d\u00e2y &amp; s\u1ee5t \u00e1p<\/h2>\n<p>Ampacity kh\u00f4ng ph\u1ea3i l\u00e0 gi\u1edbi h\u1ea1n duy nh\u1ea5t \u2014 ch\u1ea1y d\u00e2y d\u00e0i l\u00e0m m\u1ea5t \u0111i\u1ec7n \u00e1p. C\u00e1c m\u1ee9c t\u1ed1i \u0111a \u0111\u01b0\u1ee3c khuy\u1ebfn ngh\u1ecb \u0111\u1ec3 gi\u1eef s\u1ee5t \u00e1p trong 3% \u1edf 240V:<\/p>\n<table>\n<thead>\n<tr>\n<th>D\u00e2y d\u1eabn<\/th>\n<th>Chi\u1ec1u d\u00e0i ch\u1ea1y t\u1ed1i \u0111a m\u1ed9t chi\u1ec1u x\u1ea5p x\u1ec9 (s\u1ee5t \u00e1p 3%)<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>3 AWG \u0111\u1ed3ng<\/td>\n<td>~147 ft<\/td>\n<\/tr>\n<tr>\n<td>2 AWG \u0111\u1ed3ng<\/td>\n<td>~185 ft<\/td>\n<\/tr>\n<tr>\n<td>\u0110\u1ed3ng 1 AWG<\/td>\n<td>~234 ft<\/td>\n<\/tr>\n<tr>\n<td>1 AWG nh\u00f4m<\/td>\n<td>~142 ft<\/td>\n<\/tr>\n<tr>\n<td>1\/0 nh\u00f4m<\/td>\n<td>~178 ft<\/td>\n<\/tr>\n<tr>\n<td>D\u00e2y \u0111\u1ed3ng 4 AWG (310.12 nh\u00e0 \u1edf)<\/td>\n<td>~116 ft<\/td>\n<\/tr>\n<tr>\n<td>D\u00e2y nh\u00f4m 2 AWG (310.12 nh\u00e0 \u1edf)<\/td>\n<td>~112 ft<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Th\u00f4ng tin chung: ampacity ph\u00f9 h\u1ee3p cho chi\u1ec1u d\u00e0i \u0111\u1ebfn kho\u1ea3ng 100 ft, n\u00ean t\u0103ng c\u1ee1 d\u00e2y l\u00ean m\u1ed9t c\u1ea5p cho chi\u1ec1u d\u00e0i t\u1eeb 100-150 ft, v\u00e0 v\u1edbi chi\u1ec1u d\u00e0i kho\u1ea3ng 150 ft tr\u1edf l\u00ean, ampacity c\u1ea7n t\u0103ng \u00edt nh\u1ea5t m\u1ed9t c\u1ea5p (v\u00ed d\u1ee5, t\u1eeb \u0111\u1ed3ng 3 AWG l\u00ean 2 AWG ho\u1eb7c t\u1eeb nh\u00f4m 1 AWG l\u00ean 1\/0). N\u00f3i chung, c\u00e1c \u0111\u01b0\u1eddng d\u00e2y d\u00e0i \u1edf v\u00f9ng n\u00f4ng th\u00f4n th\u01b0\u1eddng c\u1ea7n t\u0103ng h\u01a1n m\u1ed9t c\u1ea5p c\u1ee1 d\u00e2y.<\/p>\n<h2>K\u00edch th\u01b0\u1edbc d\u00e2y trung t\u00ednh &amp; d\u00e2y n\u1ed1i \u0111\u1ea5t<\/h2>\n<p>Vi\u1ec7c l\u1eafp \u0111\u1eb7t \u0111\u1ea7y \u0111\u1ee7 cho 100A ph\u1ea3i bao g\u1ed3m d\u00e2y trung t\u00ednh v\u00e0 d\u00e2y n\u1ed1i \u0111\u1ea5t nh\u01b0 sau:<\/p>\n<ul>\n<li>Trung t\u00ednh: X\u00e1c \u0111\u1ecbnh ch\u00ednh x\u00e1c theo t\u1ea3i kh\u00f4ng c\u00e2n b\u1eb1ng \u0111\u00e3 t\u00ednh (B\u1ea3ng NEC 220), t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi d\u00e2y n\u00f3ng c\u1ee7a m\u1ea1ch cho d\u1ecbch v\u1ee5 100A trong h\u1ea7u h\u1ebft c\u00e1c tr\u01b0\u1eddng h\u1ee3p, trong khi c\u00f3 th\u1ec3 gi\u1ea3m m\u1ed9t k\u00edch c\u1ee1 n\u1ebfu ph\u00e9p t\u00ednh cho ph\u00e9p.<\/li>\n<li>D\u00e2y \u0111i\u1ec7n c\u1ef1c n\u1ed1i \u0111\u1ea5t (GEC) \u2013 k\u00edch th\u01b0\u1edbc theo b\u1ea3ng NEC 250.66 \u2013 GEC th\u01b0\u1eddng l\u00e0 \u0111\u1ed3ng 8AWG t\u1ed1i thi\u1ec3u cho d\u00e2y d\u1ecbch v\u1ee5 \u0111\u1ed3ng 4AWG ho\u1eb7c nh\u00f4m 2 AWG; ki\u1ec3m tra b\u1ea3ng \u0111\u1ec3 ch\u1ecdn k\u00edch th\u01b0\u1edbc d\u00e2y ph\u00f9 h\u1ee3p.<\/li>\n<li>D\u00e2y n\u1ed1i \u0111\u1ea5t thi\u1ebft b\u1ecb (ph\u1ee5): k\u00edch th\u01b0\u1edbc theo b\u1ea3ng NEC 250.122 \u2013 th\u01b0\u1eddng l\u00e0 \u0111\u1ed3ng 8 AWG ho\u1eb7c nh\u00f4m 6 AWG cho feeder 100A.<\/li>\n<li>\u0110i\u1ec7n c\u1ef1c n\u1ed1i \u0111\u1ea5t: cho d\u1ecbch v\u1ee5 t\u00f2a nh\u00e0 \u0111\u01b0\u1ee3c n\u1ed1i \u0111\u1ea5t b\u1eb1ng hai c\u1ecdc c\u00e1ch xa nhau h\u1ee3p l\u00fd (b\u1ea3ng NEC 250.52).<\/li>\n<\/ul>\n<p>\u0110\u00e2y l\u00e0 m\u1ed9t trong nh\u1eefng l\u1ed7i ph\u1ed5 bi\u1ebfn d\u1ec5 ki\u1ec3m so\u00e1t trong c\u00f4ng vi\u1ec7c d\u1ecbch v\u1ee5 khi nh\u1ea7m l\u1eabn gi\u1eefa b\u1ea3ng 250.66 (GEC) v\u00e0 250.122 (d\u00e2y n\u1ed1i \u0111\u1ea5t thi\u1ebft b\u1ecb) \u2013 h\u00e3y ch\u1ecdn b\u1ea3ng \u0111\u00fang cho d\u00e2y \u0111\u00fang.<\/p>\n<h2>Chi ti\u1ebft v\u1ec1 b\u1ea3ng ph\u1ee5: Gara t\u00e1ch r\u1eddi &amp; X\u01b0\u1edfng l\u00e0m vi\u1ec7c<\/h2>\n<p>Ch\u1ea1y 100A \u0111\u1ebfn gara t\u00e1ch r\u1eddi, x\u01b0\u1edfng l\u00e0m vi\u1ec7c ho\u1eb7c ADU c\u00f3 c\u00e1c quy \u0111\u1ecbnh v\u00e0 m\u00e3 b\u1ed5 sung c\u1ea7n xem x\u00e9t:<\/p>\n<ul>\n<li>Ph\u1ea3i l\u1eafp \u0111\u1eb7t feeder 4 d\u00e2y; bao g\u1ed3m hai d\u00e2y n\u00f3ng t\u1eeb b\u1ea3ng ch\u00ednh, m\u1ed9t d\u00e2y trung t\u00ednh v\u00e0 m\u1ed9t d\u00e2y n\u1ed1i \u0111\u1ea5t thi\u1ebft b\u1ecb (NEC 250.32). L\u01b0u \u00fd r\u1eb1ng vi\u1ec7c l\u1eafp \u0111\u1eb7t feeder 3 d\u00e2y trong t\u00f2a nh\u00e0 t\u00e1ch r\u1eddi l\u00e0 kh\u00f4ng ch\u1ea5p nh\u1eadn \u0111\u01b0\u1ee3c.<\/li>\n<li>D\u00e2y trung t\u00ednh ph\u1ea3i \u0111\u01b0\u1ee3c c\u00e1ch ly. B\u1ea1n ph\u1ea3i \u0111\u1ea3m b\u1ea3o thanh trung t\u00ednh trong b\u1ea3ng ph\u1ee5 \u0111\u01b0\u1ee3c \u0111\u1eb7t ri\u00eang bi\u1ec7t v\u1edbi thanh n\u1ed1i \u0111\u1ea5t. B\u1ea3ng ch\u00ednh s\u1ebd cung c\u1ea5p li\u00ean k\u1ebft gi\u1eefa hai thanh n\u00e0y.<\/li>\n<li>N\u1ed1i \u0111\u1ea5t l\u00e0 c\u1ea7n thi\u1ebft cho c\u1ea5u tr\u00fac m\u1edbi. T\u00f2a nh\u00e0 t\u00e1ch r\u1eddi n\u00ean c\u00f3 h\u1ec7 th\u1ed1ng n\u1ed1i \u0111\u1ea5t ri\u00eang (th\u01b0\u1eddng l\u00e0 c\u00e1c c\u1ecdc n\u1ed1i \u0111\u1ea5t \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng).<\/li>\n<li>Lo\u1ea1i c\u00e1p th\u01b0\u1eddng l\u00e0 nh\u00f4m SER 1 AWG ho\u1eb7c \u0111\u1ed3ng 3 AWG trong \u1ed1ng d\u1eabn cho feeder 100A; ph\u1ea3i tu\u00e2n th\u1ee7 310.16.<\/li>\n<li>Th\u1ef1c hi\u1ec7n t\u00ednh to\u00e1n t\u1ea3i \u2013 r\u1ea5t quan tr\u1ecdng \u0111\u1ec3 th\u1ef1c hi\u1ec7n t\u00ednh to\u00e1n t\u1ea3i tr\u01b0\u1edbc khi mua d\u00e2y. M\u1ed9t ADU c\u00f3 h\u1ec7 th\u1ed1ng s\u01b0\u1edfi \u0111i\u1ec7n v\u00e0 b\u1ed9 s\u1ea1c EV c\u00f3 th\u1ec3 c\u1ea7n 125A thay v\u00ec 100A.<\/li>\n<\/ul>\n<h2>C\u00e1c l\u1ed7i ph\u1ed5 bi\u1ebfn trong l\u1eafp \u0111\u1eb7t 100A<\/h2>\n<p style=\"text-align: center;\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-full wp-image-3847\" src=\"https:\/\/huyuglobal.com\/wp-content\/uploads\/2026\/08\/Common-Mistakes-on-100A-Installations.webp\" alt=\"C\u00e1c l\u1ed7i ph\u1ed5 bi\u1ebfn trong l\u1eafp \u0111\u1eb7t 100A\" width=\"1448\" height=\"1086\" \/><\/p>\n<table>\n<thead>\n<tr>\n<th>Sai l\u1ea7m<\/th>\n<th>T\u1ea1i sao sai<\/th>\n<th>C\u00e1ch ti\u1ebfp c\u1eadn \u0111\u00fang<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>S\u1eed d\u1ee5ng \u0111\u1ed3ng 4 AWG cho b\u1ea3ng ph\u1ee5<\/td>\n<td>4 AWG ch\u1ec9 ch\u1ecbu \u0111\u01b0\u1ee3c 85A \u2014 quy t\u1eafc 83% kh\u00f4ng \u00e1p d\u1ee5ng cho feeder<\/td>\n<td>\u0110\u1ed3ng 3 AWG ho\u1eb7c nh\u00f4m 1 AWG cho feeder 100A<\/td>\n<\/tr>\n<tr>\n<td>S\u1eed d\u1ee5ng 310.16 cho d\u1ecbch v\u1ee5 nh\u00e0 \u1edf<\/td>\n<td>\u00c9p bu\u1ed9c d\u00f9ng \u0111\u1ed3ng 3 AWG trong khi \u0111\u1ed3ng 4 AWG h\u1ee3p ph\u00e1p \u2014 l\u00e3ng ph\u00ed ti\u1ec1n<\/td>\n<td>S\u1eed d\u1ee5ng 310.12 cho nh\u00e0 \u1edf \u0111\u01a1n pha 120\/240V<\/td>\n<\/tr>\n<tr>\n<td>6 AWG \u201ctr\u00f4ng g\u1ea7n \u0111\u1ee7\u201d<\/td>\n<td>65A \u2014 nguy c\u01a1 qu\u00e1 t\u1ea3i nghi\u00eam tr\u1ecdng<\/td>\n<td>Kh\u00f4ng bao gi\u1edd \u0111o k\u00edch th\u01b0\u1edbc b\u1eb1ng c\u00e1ch \u0111o\u00e1n; h\u00e3y s\u1eed d\u1ee5ng b\u1ea3ng<\/td>\n<\/tr>\n<tr>\n<td>Feeder 3 d\u00e2y \u0111\u1ebfn t\u00f2a nh\u00e0 t\u00e1ch r\u1eddi<\/td>\n<td>Kh\u00f4ng c\u00f3 d\u00e2y n\u1ed1i \u0111\u1ea5t ri\u00eang \u2014 vi ph\u1ea1m quy chu\u1ea9n, nguy c\u01a1 \u0111i\u1ec7n gi\u1eadt<\/td>\n<td>D\u00e2y c\u1ea5p 4 d\u00e2y + \u0111i\u1ec7n c\u1ef1c n\u1ed1i \u0111\u1ea5t t\u1ea1i t\u00f2a nh\u00e0<\/td>\n<\/tr>\n<tr>\n<td>N\u1ed1i trung t\u00ednh v\u1edbi \u0111\u1ea5t trong b\u1ea3ng ph\u1ee5<\/td>\n<td>T\u1ea1o \u0111\u01b0\u1eddng tr\u1ea3 song song \u2014 nguy hi\u1ec3m<\/td>\n<td>Gi\u1eef thanh trung t\u00ednh v\u00e0 thanh n\u1ed1i \u0111\u1ea5t ri\u00eang bi\u1ec7t trong b\u1ea3ng ph\u1ee5<\/td>\n<\/tr>\n<tr>\n<td>Nh\u00f4m kh\u00f4ng c\u00f3 h\u1ee3p ch\u1ea5t\/xi\u1ebft l\u1ef1c<\/td>\n<td>\u0110\u1ea7u n\u1ed1i b\u1ecb oxy h\u00f3a qu\u00e1 nhi\u1ec7t<\/td>\n<td>H\u1ee3p ch\u1ea5t n\u1ed1i + \u0111\u1ea7u c\u1ed1t \u0111\u1ea1t chu\u1ea9n AL + th\u00f4ng s\u1ed1 xi\u1ebft l\u1ef1c<\/td>\n<\/tr>\n<tr>\n<td>B\u1ecf qua chi\u1ec1u d\u00e0i ch\u1ea1y d\u00e2y<\/td>\n<td>S\u1ee5t \u00e1p l\u00e0m suy gi\u1ea3m \u0111i\u1ec7n \u00e1p \u1edf \u0111\u1ea7u xa<\/td>\n<td>T\u0103ng k\u00edch th\u01b0\u1edbc d\u00e2y v\u01b0\u1ee3t qu\u00e1 ~100-150 ft<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>C\u00e2n nh\u1eafc v\u1ec1 chi ph\u00ed &amp; gi\u1ea5y ph\u00e9p<\/h2>\n<p>N\u00e2ng c\u1ea5p l\u00ean d\u1ecbch v\u1ee5 100A ho\u1eb7c l\u1eafp \u0111\u1eb7t d\u00e2y c\u1ea5p \u0111i\u1ec7n m\u1edbi c\u00f3 c\u00e1c chi ph\u00ed sau:<\/p>\n<ul>\n<li>V\u1eadt li\u1ec7u bao g\u1ed3m: b\u1ea3ng \u0111i\u1ec7n \u2013 $60-$200, c\u1ea7u dao ch\u00ednh 100A \u2013 $30-$80, d\u00e2y SER nh\u00f4m 2-2-2-4 \u2013 $1.50-$3 m\u1ed7i foot, d\u00e2y \u0111\u1ed3ng 3 AWG \u2013 $3-$6 m\u1ed7i foot, \u0111\u1ebf \u0111\u1ed3ng h\u1ed3 v\u00e0 ph\u1ee5 ki\u1ec7n \u2013 $50-$150.<\/li>\n<li>C\u00f4ng vi\u1ec7c s\u1ebd c\u00f3 chi ph\u00ed t\u1eeb $800-$2,500 cho n\u00e2ng c\u1ea5p d\u1ecbch v\u1ee5 v\u00e0 $500-$1,500 cho d\u00e2y c\u1ea5p b\u1ea3ng ph\u1ee5, t\u00f9y theo kho\u1ea3ng c\u00e1ch ch\u1ea1y d\u00e2y v\u00e0 vi\u1ec7c ti\u1ebfp c\u1eadn qua t\u01b0\u1eddng.<\/li>\n<li>Gi\u1ea5y ph\u00e9p v\u00e0 ki\u1ec3m tra th\u01b0\u1eddng c\u00f3 chi ph\u00ed $50-$300 v\u00e0 l\u00e0 b\u1eaft bu\u1ed9c. Thanh tra s\u1ebd ki\u1ec3m tra k\u00edch th\u01b0\u1edbc d\u00e2y v\u00e0 n\u1ed1i \u0111\u1ea5t c\u0169ng nh\u01b0 vi\u1ec7c li\u00ean k\u1ebft ho\u00e0n thi\u1ec7n.<\/li>\n<li>C\u1ea7n ph\u1ed1i h\u1ee3p v\u1edbi c\u00f4ng ty \u0111i\u1ec7n l\u1ef1c v\u00ec h\u1ecd s\u1ebd s\u1edf h\u1eefu \u0111\u1ed3ng h\u1ed3 v\u00e0 \u0111i\u1ec3m k\u1ebft n\u1ed1i d\u1ecbch v\u1ee5.<\/li>\n<\/ul>\n<p>Khi d\u1ef1 \u00e1n c\u0169ng bao g\u1ed3m b\u1ea3ng \u0111i\u1ec7n v\u00e0 c\u1ea7u dao, vi\u1ec7c ch\u1ecdn thi\u1ebft b\u1ecb b\u1ea3o v\u1ec7 \u0111\u01b0\u1ee3c ch\u1ee9ng nh\u1eadn ph\u00f9 h\u1ee3p \u2014 v\u00e0 hi\u1ec3u c\u00e1c lo\u1ea1i c\u1ea7u dao li\u00ean quan, t\u1eeb c\u01a1 b\u1ea3n c\u1ee7a <a href=\"https:\/\/huyuglobal.com\/vi\/blog\/what-is-mccb-and-mcb\/\" rel=\"nofollow\">MCB v\u00e0 MCCB<\/a> vi\u1ec7c <a href=\"https:\/\/huyuglobal.com\/vi\/blog\/what-is-ul-489-breakers\/\" rel=\"nofollow\">ti\u00eau chu\u1ea9n b\u1ed9 ng\u1eaft UL 489<\/a> \u2014 gi\u00fap to\u00e0n b\u1ed9 h\u1ec7 th\u1ed1ng tu\u00e2n th\u1ee7 quy chu\u1ea9n t\u1eeb \u0111\u1ea7u \u0111\u1ebfn cu\u1ed1i. V\u00e0 khi c\u1ea7u dao ch\u00ednh 100A \u0111\u01b0\u1ee3c l\u1eafp \u0111\u1eb7t, m\u1ecdi m\u1ea1ch nh\u00e1nh ph\u00eda sau \u0111\u1ec1u tu\u00e2n theo quy t\u1eafc k\u00edch th\u01b0\u1edbc t\u01b0\u01a1ng t\u1ef1 \u2014 c\u00e1c gi\u1edbi h\u1ea1n \u0111\u01b0\u1ee3c gi\u1ea3i th\u00edch cho <a href=\"https:\/\/huyuglobal.com\/vi\/blog\/how-many-watts-on-a-15-amp-circuit\/\" rel=\"nofollow\">c\u00f4ng su\u1ea5t m\u1ea1ch 15 amp<\/a> \u00e1p d\u1ee5ng \u1edf m\u1ecdi c\u1ea5p \u0111\u1ed9 c\u1ee7a b\u1ea3ng \u0111i\u1ec7n.<\/p>\n<h2>Ti\u00eau chu\u1ea9n qu\u1ed1c t\u1ebf: M\u1ed9t ghi ch\u00fa nhanh<\/h2>\n<p>Ngo\u00e0i B\u1eafc M\u1ef9, vi\u1ec7c x\u00e1c \u0111\u1ecbnh d\u00e2y 100A \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n kh\u00e1c do ph\u1ea7n l\u1edbn th\u1ebf gi\u1edbi \u00e1p d\u1ee5ng c\u00e1c ph\u01b0\u01a1ng ph\u00e1p ph\u00f9 h\u1ee3p v\u1edbi ti\u00eau chu\u1ea9n IEC\/BS 7671 (ph\u01b0\u01a1ng ph\u00e1p d\u00f2ng \u0111i\u1ec7n v\u00e0 h\u1ec7 s\u1ed1 hi\u1ec7u ch\u1ec9nh) thay v\u00ec s\u1eed d\u1ee5ng b\u1ea3ng d\u1ecbch v\u1ee5 \u0111\u01a1n gi\u1ea3n.<\/p>\n<ul>\n<li>\u1ede V\u01b0\u01a1ng qu\u1ed1c Anh (BS 7671), k\u00edch th\u01b0\u1edbc c\u00e1p \u0111\u01b0\u1ee3c x\u00e1c \u0111\u1ecbnh d\u1ef1a tr\u00ean ph\u01b0\u01a1ng ph\u00e1p l\u1eafp \u0111\u1eb7t. V\u00ed d\u1ee5, k\u1ebft n\u1ed1i m\u1ed9t pha 100A th\u01b0\u1eddng y\u00eau c\u1ea7u d\u00e2y \u0111\u1ed3ng t\u1eeb 25 \u0111\u1ebfn 50mm\u00b2 t\u00f9y theo chi\u1ec1u d\u00e0i c\u00e1p.<\/li>\n<li>\u1ede ch\u00e2u \u00c2u (IEC 60364), ph\u01b0\u01a1ng ph\u00e1p \u0111\u01a1n gi\u1ea3n \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng.<\/li>\n<li>\u1ede \u00dac (AS\/NZS 3000), c\u00e1c ph\u00e9p t\u00ednh d\u1ef1a tr\u00ean ph\u01b0\u01a1ng ph\u00e1p \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng cho c\u00e1ch \u0111i\u1ec7n v\u00e0 th\u01b0\u1eddng d\u1eabn \u0111\u1ebfn vi\u1ec7c s\u1eed d\u1ee5ng d\u00e2y 25 \u0111\u1ebfn 35mm\u00b2.<\/li>\n<li>\u1ede Canada (CE Code), l\u1eadp lu\u1eadn t\u01b0\u01a1ng t\u1ef1 nh\u01b0 NEC \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng; c\u00e1c l\u1eafp \u0111\u1eb7t c\u00f3 th\u1ec3 d\u1ef1a tr\u00ean c\u00e1c c\u00f4ng th\u1ee9c t\u01b0\u01a1ng t\u1ef1 83%.<\/li>\n<\/ul>\n<p>Quy tr\u00ecnh NEC d\u1ef1a tr\u00ean c\u00e1c quy t\u1eafc d\u00e0nh ri\u00eang cho l\u1eafp \u0111\u1eb7t t\u1ea1i M\u1ef9 v\u00e0\/ho\u1eb7c Canada; do \u0111\u00f3, n\u1ebfu v\u1ecb tr\u00ed c\u00f4ng vi\u1ec7c kh\u00e1c hai n\u01a1i n\u00e0y, n\u00ean thu\u00ea k\u1ef9 s\u01b0 ho\u1eb7c th\u1ee3 \u0111i\u1ec7n \u0111\u1ec3 th\u1ef1c hi\u1ec7n c\u00e1c ph\u00e9p t\u00ednh.<\/p>\n<h2>C\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p<\/h2>\n<h3>Ch\u00fang ta c\u1ea7n k\u00edch th\u01b0\u1edbc d\u00e2y bao nhi\u00eau cho d\u1ecbch v\u1ee5 100 amp?<\/h3>\n<p>Theo NEC 310.12 \u0111\u1ed1i v\u1edbi h\u1ec7 th\u1ed1ng d\u00e2n d\u1ee5ng v\u1edbi d\u1ecbch v\u1ee5 100A (pha \u0111\u01a1n), \u0111\u01b0\u1ee3c ph\u00e9p s\u1eed d\u1ee5ng d\u00e2y d\u1eabn \u0111\u1ed3ng 4 AWG ho\u1eb7c d\u00e2y d\u1eabn nh\u00f4m 2 AWG. Trong khi \u0111\u00f3, \u0111\u1ed1i v\u1edbi h\u1ec7 th\u1ed1ng th\u01b0\u01a1ng m\u1ea1i v\u1edbi ba pha ho\u1eb7c h\u1ec7 th\u1ed1ng t\u1ee7 ph\u1ee5 100A, ph\u1ea3i \u00e1p d\u1ee5ng \u0111\u1ea7y \u0111\u1ee7 ampacity theo NEC 310.16, ngh\u0129a l\u00e0 t\u1ed1i thi\u1ec3u d\u00e2y d\u1eabn \u0111\u1ed3ng 3 AWG ho\u1eb7c d\u00e2y d\u1eabn nh\u00f4m 1 AWG. V\u1ec1 k\u00edch th\u01b0\u1edbc cho GEC, ph\u1ea3i s\u1eed d\u1ee5ng d\u00e2y d\u1eabn \u0111\u1ed3ng 8 AWG theo 250.66 c\u00f9ng v\u1edbi vi\u1ec7c t\u0103ng k\u00edch th\u01b0\u1edbc cho kho\u1ea3ng c\u00e1ch tr\u00ean 100-150 feet.<\/p>\n<h3>D\u00e2y \u0111\u1ed3ng #3 c\u00f3 ph\u00f9 h\u1ee3p cho 100 ampe kh\u00f4ng?<\/h3>\n<p>Th\u1eadt v\u1eady \u2013 d\u00e2y \u0111\u1ed3ng 3 AWG \u0111\u01b0\u1ee3c \u0111\u1ecbnh m\u1ee9c ch\u00ednh x\u00e1c l\u00e0 100A \u1edf 75\u00b0C, \u0111\u00e2y ch\u00ednh l\u00e0 m\u1ee9c t\u1ed1i thi\u1ec3u y\u00eau c\u1ea7u cho m\u1ea1ch 100A th\u00f4ng th\u01b0\u1eddng, d\u1ecbch v\u1ee5 th\u01b0\u01a1ng m\u1ea1i ho\u1eb7c c\u1ea5p ngu\u1ed3n t\u1ee7 ph\u1ee5 d\u1ef1a tr\u00ean NEC 310.16. Tuy nhi\u00ean, nhi\u1ec1u th\u1ee3 \u0111i\u1ec7n s\u1eed d\u1ee5ng d\u00e2y \u0111\u1ed3ng 2 AWG (115A) \u0111\u1ec3 cung c\u1ea5p th\u00eam dung l\u01b0\u1ee3ng do gi\u1ea3m \u0111\u1ecbnh m\u1ee9c. \u0110\u1ed1i v\u1edbi d\u1ecbch v\u1ee5 h\u1ed9 gia \u0111\u00ecnh, d\u00e2y \u0111\u1ed3ng 4 AWG \u0111\u01b0\u1ee3c xem l\u00e0 ph\u00f9 h\u1ee3p.<\/p>\n<h3>D\u00e2y 2-2-2-4 c\u00f3 ph\u00f9 h\u1ee3p cho 100 ampe kh\u00f4ng?<\/h3>\n<p>Th\u1eadt v\u1eady, \u0111\u1ed1i v\u1edbi \u1ee9ng d\u1ee5ng d\u00e2n d\u1ee5ng, c\u00e1p SER \u201c2-2-2-4\u201d (2 d\u00e2y n\u00f3ng 2 AWG, 1 d\u00e2y trung t\u00ednh 2 AWG, v\u00e0 1 d\u00e2y n\u1ed1i \u0111\u1ea5t 4 AWG) \u0111\u01b0\u1ee3c xem l\u00e0 lo\u1ea1i nh\u00f4m ti\u00eau chu\u1ea9n cho d\u1ecbch v\u1ee5 d\u00e2n d\u1ee5ng 100A nh\u01b0 quy \u0111\u1ecbnh trong NEC 310.12 (c\u1ea7n l\u01b0u \u00fd r\u1eb1ng d\u00e2y nh\u00f4m 2 AWG \u0111\u01b0\u1ee3c \u0111\u1ecbnh m\u1ee9c 90A, \u0111\u1ee7 cho 83A c\u1ea7n thi\u1ebft). Nh\u01b0ng \u0111\u1ed1i v\u1edbi \u1ee9ng d\u1ee5ng th\u01b0\u01a1ng m\u1ea1i, c\u1ea7n d\u00e2y nh\u00f4m 1 AWG ho\u1eb7c d\u00e2y \u0111\u1ed3ng 3 AWG cho d\u1ecbch v\u1ee5 th\u01b0\u01a1ng m\u1ea1i 100A.<\/p>\n<h3>D\u00e2y c\u1ee1 6 c\u00f3 ch\u1ecbu \u0111\u01b0\u1ee3c 100 ampe kh\u00f4ng?<\/h3>\n<p>Kh\u00f4ng. D\u00e2y \u0111\u1ed3ng 6 AWG c\u00f3 \u0111\u1ecbnh m\u1ee9c ch\u1ec9 65 ampe \u1edf nhi\u1ec7t \u0111\u1ed9 75\u00b0C (55 ampe \u1edf 60\u00b0C), kh\u00f4ng ph\u00f9 h\u1ee3p cho 100 ampe. D\u00e2y s\u1ebd n\u00f3ng l\u00ean, g\u00e2y nguy c\u01a1 ch\u00e1y r\u1ea5t cao. D\u00e2y \u0111\u1ed3ng 6 AWG ph\u00f9 h\u1ee3p cho m\u1ea1ch mang d\u00f2ng 50-60 ampe (v\u00ed d\u1ee5 v\u1edbi b\u1ebfp, l\u00f2 n\u01b0\u1edbng ho\u1eb7c t\u1ee7 ph\u1ee5 nh\u1ecf). \u0110\u1ed1i v\u1edbi 100A, s\u1eed d\u1ee5ng d\u00e2y \u0111\u1ed3ng 3 AWG ho\u1eb7c d\u00e2y nh\u00f4m 1 AWG (n\u00f3i chung) ho\u1eb7c d\u00e2y \u0111\u1ed3ng 4 AWG ho\u1eb7c d\u00e2y nh\u00f4m 2 AWG (cho d\u1ecbch v\u1ee5 nh\u00e0 \u1edf).<\/p>\n<h2>T\u00e0i li\u1ec7u tham kh\u1ea3o<\/h2>\n<ol>\n<li><a href=\"https:\/\/www.nfpa.org\/codes-and-standards\/nfpa-70-standard-development\" rel=\"nofollow noopener\" target=\"_blank\">NFPA 70 \u2014 National Electrical Code (NEC): C\u00e1c \u0111i\u1ec1u 230, 240, 250, 310<\/a><\/li>\n<li><a href=\"https:\/\/www.mikeholt.com\/code_changes.php\" rel=\"nofollow noopener\" target=\"_blank\">Mike Holt \u2014 NEC 310.12 Quy t\u1eafc 83% v\u00e0 K\u00edch th\u01b0\u1edbc D\u00e2y d\u1eabn<\/a><\/li>\n<li><a href=\"https:\/\/www.osha.gov\/laws-regs\/regulations\/standardnumber\/1910\/1910.303\" rel=\"nofollow noopener\" target=\"_blank\">OSHA 1910.303 \u2014 Y\u00eau c\u1ea7u \u0111i\u1ec7n t\u1ed5ng qu\u00e1t<\/a><\/li>\n<li><a href=\"https:\/\/www.ecmweb.com\/\" rel=\"nofollow noopener\" target=\"_blank\">T\u1ea1p ch\u00ed EC&amp;M \u2014 C\u00e1c b\u00e0i vi\u1ebft v\u1ec1 K\u00edch th\u01b0\u1edbc D\u1ecbch v\u1ee5 v\u00e0 D\u00e2y c\u1ea5p ngu\u1ed3n<\/a><\/li>\n<li><a href=\"https:\/\/webstore.iec.ch\/\" rel=\"nofollow noopener\" target=\"_blank\">IEC 60364 \u2014 L\u1eafp \u0111\u1eb7t \u0111i\u1ec7n \u00e1p th\u1ea5p (Qu\u1ed1c t\u1ebf)<\/a><\/li>\n<li><a href=\"https:\/\/www.nema.org\/\" rel=\"nofollow noopener\" target=\"_blank\">NEMA \u2014 Ti\u00eau chu\u1ea9n D\u00e2y d\u1eabn v\u00e0 \u0110i\u1ec7n<\/a><\/li>\n<\/ol>\n<h2>K\u1ebft lu\u1eadn<\/h2>\n<p>Qu\u00e1 tr\u00ecnh x\u00e1c \u0111\u1ecbnh k\u00edch th\u01b0\u1edbc d\u00e2y ph\u00f9 h\u1ee3p cho d\u1ecbch v\u1ee5 \u0111\u1ecbnh m\u1ee9c 100 A ph\u1ee5 thu\u1ed9c v\u00e0o c\u00e2u tr\u1ea3 l\u1eddi cho c\u00e2u h\u1ecfi: quy t\u1eafc 83% cho nh\u00e0 \u1edf c\u00f3 \u00e1p d\u1ee5ng kh\u00f4ng? Theo NEC 310.12, trong tr\u01b0\u1eddng h\u1ee3p \u1ee9ng d\u1ee5ng d\u00e2n d\u1ee5ng, th\u1ef1c h\u00e0nh k\u00edch th\u01b0\u1edbc d\u00e2y ti\u00eau chu\u1ea9n y\u00eau c\u1ea7u s\u1eed d\u1ee5ng d\u00e2y \u0111\u1ed3ng 4 AWG ho\u1eb7c d\u00e2y nh\u00f4m 2 AWG. Trong tr\u01b0\u1eddng h\u1ee3p l\u1eafp \u0111\u1eb7t th\u01b0\u01a1ng m\u1ea1i, h\u1ec7 th\u1ed1ng c\u00f3 \u0111\u1ed9ng c\u01a1 ba pha v\u00e0 t\u1ee7 ph\u1ee5 100 ampe, k\u00edch th\u01b0\u1edbc d\u00e2y \u00e1p d\u1ee5ng theo y\u00eau c\u1ea7u m\u00e3 li\u00ean quan \u0111\u1ebfn ampacity t\u01b0\u01a1ng \u1ee9ng v\u1edbi d\u00e2y \u0111\u1ed3ng 3 AWG ho\u1eb7c d\u00e2y nh\u00f4m 1 AWG; do \u0111\u00f3, trong th\u1ef1c t\u1ebf, d\u00e2y \u0111\u1ed3ng 2 AWG th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng. Khi t\u1ee7 \u0111i\u1ec7n v\u00e0 c\u1ea7u dao l\u00e0 m\u1ed9t ph\u1ea7n c\u1ee7a c\u00f4ng vi\u1ec7c, vi\u1ec7c hi\u1ec3u c\u00e1c thi\u1ebft b\u1ecb b\u1ea3o v\u1ec7 \u2014 nh\u01b0 <a href=\"https:\/\/huyuglobal.com\/vi\/blog\/how-to-tell-if-a-breaker-is-bad\/\" rel=\"nofollow\">nh\u1eadn bi\u1ebft c\u1ea7u dao b\u1ecb l\u1ed7i<\/a> v\u00e0 gi\u00e1 th\u1ef1c t\u1ebf trong <a href=\"https:\/\/huyuglobal.com\/vi\/blog\/how-much-to-replace-a-circuit-breaker\/\" rel=\"nofollow\">chi ph\u00ed thay th\u1ebf c\u1ea7u dao<\/a> \u2014 gi\u1eef cho to\u00e0n b\u1ed9 d\u1ef1 \u00e1n an to\u00e0n, h\u1ee3p ph\u00e1p v\u00e0 trong ng\u00e2n s\u00e1ch.<\/p>","protected":false},"excerpt":{"rendered":"<p>Whether you are upgrading your old residential home service from 60A to 100A, installing a feeder line to a detached garage, or wiring a new workshop, the first question is always the same \u2014 what kind of wiring (copper or aluminum) do I need for a 100 amp service? The answer rests upon two different [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":3844,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_gspb_post_css":"","footnotes":""},"categories":[1],"tags":[],"class_list":["post-3843","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blogs"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/huyuglobal.com\/vi\/wp-json\/wp\/v2\/posts\/3843","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/huyuglobal.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/huyuglobal.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/huyuglobal.com\/vi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/huyuglobal.com\/vi\/wp-json\/wp\/v2\/comments?post=3843"}],"version-history":[{"count":2,"href":"https:\/\/huyuglobal.com\/vi\/wp-json\/wp\/v2\/posts\/3843\/revisions"}],"predecessor-version":[{"id":3849,"href":"https:\/\/huyuglobal.com\/vi\/wp-json\/wp\/v2\/posts\/3843\/revisions\/3849"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/huyuglobal.com\/vi\/wp-json\/wp\/v2\/media\/3844"}],"wp:attachment":[{"href":"https:\/\/huyuglobal.com\/vi\/wp-json\/wp\/v2\/media?parent=3843"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/huyuglobal.com\/vi\/wp-json\/wp\/v2\/categories?post=3843"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/huyuglobal.com\/vi\/wp-json\/wp\/v2\/tags?post=3843"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}