{"id":4262,"date":"2026-09-28T00:00:00","date_gmt":"2026-09-28T00:00:00","guid":{"rendered":"https:\/\/chac-electric.com\/?p=4262"},"modified":"2026-09-18T08:07:47","modified_gmt":"2026-09-18T08:07:47","slug":"bo-ngat-mach-thu-nho-20-amp","status":"publish","type":"post","link":"https:\/\/chac-electric.com\/vi\/blog\/miniature-circuit-breaker-20-amp\/","title":{"rendered":"B\u1ed9 ng\u1eaft m\u1ea1ch thu nh\u1ecf 20 amp"},"content":{"rendered":"

Khi m\u1ed9t d\u1ef1 \u00e1n g\u1eb7p v\u1ea5n \u0111\u1ec1 l\u1ef1a ch\u1ecdn thi\u1ebft b\u1ecb, s\u1ef1 th\u1ea5t b\u1ea1i r\u00f5 r\u00e0ng th\u01b0\u1eddng xu\u1ea5t hi\u1ec7n tr\u01b0\u1edbc khi nguy\u00ean nh\u00e2n th\u1ef1c s\u1ef1 \u0111\u01b0\u1ee3c hi\u1ec3u r\u00f5. Noah, m\u1ed9t gi\u00e1m s\u00e1t vi\u00ean thi c\u00f4ng t\u1ea1i Seattle, \u0111\u00e3 l\u1eafp m\u1ed9t thi\u1ebft b\u1ecb MCB c\u00f4ng su\u1ea5t 20 A v\u00e0o m\u1ed9t \u0111\u01b0\u1eddng d\u00e2y \u0111i\u1ec7n v\u00ec ph\u00edch c\u1eafm c\u1ee7a thi\u1ebft b\u1ecb ph\u00f9 h\u1ee3p. Ph\u01b0\u01a1ng ph\u00e1p l\u1eafp \u0111\u1eb7t c\u00e1p v\u00e0 t\u1ea3i li\u00ean t\u1ee5c ch\u01b0a \u0111\u01b0\u1ee3c ki\u1ec3m tra. L\u1ecbch tr\u00ecnh s\u1eeda \u0111\u1ed5i \u0111\u00e3 ph\u00f9 h\u1ee3p v\u1edbi c\u00f4ng su\u1ea5t d\u00e2y d\u1eabn v\u00e0 bao g\u1ed3m m\u1ed9t m\u1ea1ch chuy\u00ean d\u1ee5ng khi c\u1ea7n thi\u1ebft.<\/p>\n

T\u00f3m t\u1eaft:<\/strong> Thi\u1ebft b\u1ecb b\u1ea3o v\u1ec7 20 A MCB b\u1ea3o v\u1ec7 m\u1ed9t m\u1ea1ch \u0111\u01b0\u1ee3c thi\u1ebft k\u1ebf \u0111\u1ec3 ch\u1ecbu t\u1ea3i l\u00ean \u0111\u1ebfn 20 ampere trong \u0111i\u1ec1u ki\u1ec7n l\u1eafp \u0111\u1eb7t; n\u00f3 kh\u00f4ng t\u1ef1 \u0111\u1ed9ng \u0111\u1ea3m b\u1ea3o an to\u00e0n cho m\u1ecdi thi\u1ebft b\u1ecb c\u00f3 t\u1ea3i 20 ampere. X\u00e1c nh\u1eadn c\u00f4ng su\u1ea5t d\u00e2y d\u1eabn, \u0111i\u1ec1u tr\u1ecb t\u1ea3i li\u00ean t\u1ee5c, \u0111i\u1ec7n \u00e1p, \u0111\u01b0\u1eddng cong tr\u1ea1ng th\u00e1i qu\u00e1 t\u1ea3i, d\u00f2ng \u0111i\u1ec7n qu\u00e1 t\u1ea3i v\u00e0 quy \u0111\u1ecbnh v\u1ec1 thi\u1ebft b\u1ecb ti\u1ebfp nh\u1eadn t\u1ea1i \u0111\u1ecba ph\u01b0\u01a1ng. B\u00e0i vi\u1ebft n\u00e0y d\u1ef1a tr\u00ean b\u1eb1ng ch\u1ee9ng \u0111\u1ec3 \u0111\u01b0a ra quy\u1ebft \u0111\u1ecbnh v\u00e0 t\u00e1ch bi\u1ec7t kh\u1ea3 n\u0103ng c\u1ee7a s\u1ea3n ph\u1ea9m v\u1edbi tr\u00e1ch nhi\u1ec7m l\u1eafp \u0111\u1eb7t.<\/p>\n

\"\u1ee8ng<\/p>\n

Nhi\u1ec7t \u0111\u1ed9 t\u1ea3i tr\u00ean nh\u00e1nh v\u00e0 quy m\u00f4 c\u00e1p<\/h2>\n

C\u00e2u tr\u1ea3 l\u1eddi \u0111\u00fang b\u1eaft \u0111\u1ea7u t\u1eeb ranh gi\u1edbi \u1ee9ng d\u1ee5ng. H\u00e3y x\u00e1c \u0111\u1ecbnh ngu\u1ed3n, t\u1ea3i, d\u00e2y d\u1eabn, m\u1ee9c \u0111\u1ed9 s\u1ef1 c\u1ed1 v\u00e0 m\u00f4i tr\u01b0\u1eddng v\u1eadn h\u00e0nh tr\u01b0\u1edbc khi so s\u00e1nh c\u00e1c catalogue. M\u1ed9t thi\u1ebft b\u1ecb tr\u00f4ng c\u00f3 v\u1ebb ph\u00f9 h\u1ee3p v\u1ec1 \u0111\u1ecbnh m\u1ee9c d\u00f2ng \u0111i\u1ec7n v\u1eabn c\u00f3 th\u1ec3 h\u1ecfng v\u1ec1 kh\u1ea3 n\u0103ng ch\u1ecbu h\u1ed3 quang, t\u00ednh ch\u1ecdn l\u1ecdc, nhi\u1ec7t \u0111\u1ed9 ho\u1eb7c ph\u01b0\u01a1ng ph\u00e1p l\u1eafp \u0111\u1eb7t. H\u00e3y s\u1eed d\u1ee5ng \u0111\u01b0\u1eddng cong th\u1eddi gian-d\u00f2ng \u0111i\u1ec7n c\u1ee7a nh\u00e0 s\u1ea3n xu\u1ea5t v\u00e0 ti\u00eau chu\u1ea9n \u0111i d\u00e2y \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng l\u00e0m ng\u00f4n ng\u1eef chung gi\u1eefa thi\u1ebft k\u1ebf, mua s\u1eafm v\u00e0 ch\u1ea1y th\u1eed.<\/p>\n

L\u1eadp t\u00e0i li\u1ec7u v\u1ec1 c\u00e1c gi\u1ea3 \u0111\u1ecbnh v\u00e0 ki\u1ec3m tra ch\u00fang t\u1ea1i t\u1ee7 \u0111i\u1ec7n. V\u00ed d\u1ee5, m\u1ed9t nghi\u00ean c\u1ee9u v\u1ec1 b\u1ea3o v\u1ec7 c\u1ea7n n\u00eau r\u00f5 d\u00f2ng \u0111i\u1ec7n ng\u1eafn m\u1ea1ch d\u1ef1 ki\u1ebfn, d\u00f2ng \u0111i\u1ec7n kh\u1edfi \u0111\u1ed9ng (inrush) d\u1ef1 ki\u1ebfn, kh\u1ea3 n\u0103ng mang d\u00f2ng c\u1ee7a d\u00e2y d\u1eabn v\u00e0 th\u1eddi gian c\u1eaft y\u00eau c\u1ea7u. C\u00e1c ph\u01b0\u01a1ng ph\u00e1p c\u00f3 t\u00ean g\u1ecdi c\u1ee5 th\u1ec3 nh\u01b0 th\u1eed nghi\u1ec7m ti\u00eam d\u00f2ng s\u01a1 c\u1ea5p, th\u1eed nghi\u1ec7m \u0111i\u1ec7n tr\u1edf c\u00e1ch \u0111i\u1ec7n ho\u1eb7c nghi\u00ean c\u1ee9u ph\u1ed1i h\u1ee3p s\u1ebd h\u1eefu \u00edch h\u01a1n so v\u1edbi m\u1ed9t tuy\u00ean b\u1ed1 chung chung r\u1eb1ng m\u1ed9t s\u1ea3n ph\u1ea9m \u0111\u1ea1t \u201cc\u1ea5p \u0111\u1ed9 c\u00f4ng nghi\u1ec7p.\u201d<\/p>\n

N\u1ebfu c\u00e2u tr\u1ea3 l\u1eddi thay \u0111\u1ed5i theo th\u1ecb tr\u01b0\u1eddng \u0111\u00edch, h\u1ec7 th\u1ed1ng \u0111i\u1ec7n \u00e1p ho\u1eb7c lo\u1ea1i \u1ee9ng d\u1ee5ng, h\u00e3y n\u00eau gi\u1ea3 \u0111\u1ecbnh \u0111\u00f3 trong th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt v\u00e0 nh\u1eadn \u0111\u01b0\u1ee3c x\u00e1c nh\u1eadn b\u1eb1ng v\u0103n b\u1ea3n tr\u01b0\u1edbc khi ph\u00e1t h\u00e0nh.<\/p>\n

L\u1ef1a ch\u1ecdn \u0111\u01b0\u1eddng cong chuy\u1ebfn \u0111i<\/h2>\n

C\u00e2u tr\u1ea3 l\u1eddi \u0111\u00fang b\u1eaft \u0111\u1ea7u t\u1eeb ranh gi\u1edbi \u1ee9ng d\u1ee5ng. H\u00e3y x\u00e1c \u0111\u1ecbnh ngu\u1ed3n, t\u1ea3i, d\u00e2y d\u1eabn, m\u1ee9c \u0111\u1ed9 s\u1ef1 c\u1ed1 v\u00e0 m\u00f4i tr\u01b0\u1eddng v\u1eadn h\u00e0nh tr\u01b0\u1edbc khi so s\u00e1nh c\u00e1c catalogue. M\u1ed9t thi\u1ebft b\u1ecb tr\u00f4ng c\u00f3 v\u1ebb ph\u00f9 h\u1ee3p v\u1ec1 \u0111\u1ecbnh m\u1ee9c d\u00f2ng \u0111i\u1ec7n v\u1eabn c\u00f3 th\u1ec3 h\u1ecfng v\u1ec1 kh\u1ea3 n\u0103ng ch\u1ecbu h\u1ed3 quang, t\u00ednh ch\u1ecdn l\u1ecdc, nhi\u1ec7t \u0111\u1ed9 ho\u1eb7c ph\u01b0\u01a1ng ph\u00e1p l\u1eafp \u0111\u1eb7t. H\u00e3y s\u1eed d\u1ee5ng \u0111\u01b0\u1eddng cong th\u1eddi gian-d\u00f2ng \u0111i\u1ec7n c\u1ee7a nh\u00e0 s\u1ea3n xu\u1ea5t v\u00e0 ti\u00eau chu\u1ea9n \u0111i d\u00e2y \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng l\u00e0m ng\u00f4n ng\u1eef chung gi\u1eefa thi\u1ebft k\u1ebf, mua s\u1eafm v\u00e0 ch\u1ea1y th\u1eed.<\/p>\n

L\u1eadp t\u00e0i li\u1ec7u v\u1ec1 c\u00e1c gi\u1ea3 \u0111\u1ecbnh v\u00e0 ki\u1ec3m tra ch\u00fang t\u1ea1i t\u1ee7 \u0111i\u1ec7n. V\u00ed d\u1ee5, m\u1ed9t nghi\u00ean c\u1ee9u v\u1ec1 b\u1ea3o v\u1ec7 c\u1ea7n n\u00eau r\u00f5 d\u00f2ng \u0111i\u1ec7n ng\u1eafn m\u1ea1ch d\u1ef1 ki\u1ebfn, d\u00f2ng \u0111i\u1ec7n kh\u1edfi \u0111\u1ed9ng (inrush) d\u1ef1 ki\u1ebfn, kh\u1ea3 n\u0103ng mang d\u00f2ng c\u1ee7a d\u00e2y d\u1eabn v\u00e0 th\u1eddi gian c\u1eaft y\u00eau c\u1ea7u. C\u00e1c ph\u01b0\u01a1ng ph\u00e1p c\u00f3 t\u00ean g\u1ecdi c\u1ee5 th\u1ec3 nh\u01b0 th\u1eed nghi\u1ec7m ti\u00eam d\u00f2ng s\u01a1 c\u1ea5p, th\u1eed nghi\u1ec7m \u0111i\u1ec7n tr\u1edf c\u00e1ch \u0111i\u1ec7n ho\u1eb7c nghi\u00ean c\u1ee9u ph\u1ed1i h\u1ee3p s\u1ebd h\u1eefu \u00edch h\u01a1n so v\u1edbi m\u1ed9t tuy\u00ean b\u1ed1 chung chung r\u1eb1ng m\u1ed9t s\u1ea3n ph\u1ea9m \u0111\u1ea1t \u201cc\u1ea5p \u0111\u1ed9 c\u00f4ng nghi\u1ec7p.\u201d<\/p>\n

N\u1ebfu c\u00e2u tr\u1ea3 l\u1eddi thay \u0111\u1ed5i theo th\u1ecb tr\u01b0\u1eddng \u0111\u00edch, h\u1ec7 th\u1ed1ng \u0111i\u1ec7n \u00e1p ho\u1eb7c lo\u1ea1i \u1ee9ng d\u1ee5ng, h\u00e3y n\u00eau gi\u1ea3 \u0111\u1ecbnh \u0111\u00f3 trong th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt v\u00e0 nh\u1eadn \u0111\u01b0\u1ee3c x\u00e1c nh\u1eadn b\u1eb1ng v\u0103n b\u1ea3n tr\u01b0\u1edbc khi ph\u00e1t h\u00e0nh.<\/p>\n

D\u00f9ng cho m\u1ee5c \u0111\u00edch d\u00e2n c\u01b0 v\u00e0 th\u01b0\u01a1ng m\u1ea1i<\/h2>\n

C\u00e2u tr\u1ea3 l\u1eddi \u0111\u00fang b\u1eaft \u0111\u1ea7u t\u1eeb ranh gi\u1edbi \u1ee9ng d\u1ee5ng. H\u00e3y x\u00e1c \u0111\u1ecbnh ngu\u1ed3n, t\u1ea3i, d\u00e2y d\u1eabn, m\u1ee9c \u0111\u1ed9 s\u1ef1 c\u1ed1 v\u00e0 m\u00f4i tr\u01b0\u1eddng v\u1eadn h\u00e0nh tr\u01b0\u1edbc khi so s\u00e1nh c\u00e1c catalogue. M\u1ed9t thi\u1ebft b\u1ecb tr\u00f4ng c\u00f3 v\u1ebb ph\u00f9 h\u1ee3p v\u1ec1 \u0111\u1ecbnh m\u1ee9c d\u00f2ng \u0111i\u1ec7n v\u1eabn c\u00f3 th\u1ec3 h\u1ecfng v\u1ec1 kh\u1ea3 n\u0103ng ch\u1ecbu h\u1ed3 quang, t\u00ednh ch\u1ecdn l\u1ecdc, nhi\u1ec7t \u0111\u1ed9 ho\u1eb7c ph\u01b0\u01a1ng ph\u00e1p l\u1eafp \u0111\u1eb7t. H\u00e3y s\u1eed d\u1ee5ng \u0111\u01b0\u1eddng cong th\u1eddi gian-d\u00f2ng \u0111i\u1ec7n c\u1ee7a nh\u00e0 s\u1ea3n xu\u1ea5t v\u00e0 ti\u00eau chu\u1ea9n \u0111i d\u00e2y \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng l\u00e0m ng\u00f4n ng\u1eef chung gi\u1eefa thi\u1ebft k\u1ebf, mua s\u1eafm v\u00e0 ch\u1ea1y th\u1eed.<\/p>\n

L\u1eadp t\u00e0i li\u1ec7u v\u1ec1 c\u00e1c gi\u1ea3 \u0111\u1ecbnh v\u00e0 ki\u1ec3m tra ch\u00fang t\u1ea1i t\u1ee7 \u0111i\u1ec7n. V\u00ed d\u1ee5, m\u1ed9t nghi\u00ean c\u1ee9u v\u1ec1 b\u1ea3o v\u1ec7 c\u1ea7n n\u00eau r\u00f5 d\u00f2ng \u0111i\u1ec7n ng\u1eafn m\u1ea1ch d\u1ef1 ki\u1ebfn, d\u00f2ng \u0111i\u1ec7n kh\u1edfi \u0111\u1ed9ng (inrush) d\u1ef1 ki\u1ebfn, kh\u1ea3 n\u0103ng mang d\u00f2ng c\u1ee7a d\u00e2y d\u1eabn v\u00e0 th\u1eddi gian c\u1eaft y\u00eau c\u1ea7u. C\u00e1c ph\u01b0\u01a1ng ph\u00e1p c\u00f3 t\u00ean g\u1ecdi c\u1ee5 th\u1ec3 nh\u01b0 th\u1eed nghi\u1ec7m ti\u00eam d\u00f2ng s\u01a1 c\u1ea5p, th\u1eed nghi\u1ec7m \u0111i\u1ec7n tr\u1edf c\u00e1ch \u0111i\u1ec7n ho\u1eb7c nghi\u00ean c\u1ee9u ph\u1ed1i h\u1ee3p s\u1ebd h\u1eefu \u00edch h\u01a1n so v\u1edbi m\u1ed9t tuy\u00ean b\u1ed1 chung chung r\u1eb1ng m\u1ed9t s\u1ea3n ph\u1ea9m \u0111\u1ea1t \u201cc\u1ea5p \u0111\u1ed9 c\u00f4ng nghi\u1ec7p.\u201d<\/p>\n

N\u1ebfu c\u00e2u tr\u1ea3 l\u1eddi thay \u0111\u1ed5i theo th\u1ecb tr\u01b0\u1eddng \u0111\u00edch, h\u1ec7 th\u1ed1ng \u0111i\u1ec7n \u00e1p ho\u1eb7c lo\u1ea1i \u1ee9ng d\u1ee5ng, h\u00e3y n\u00eau gi\u1ea3 \u0111\u1ecbnh \u0111\u00f3 trong th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt v\u00e0 nh\u1eadn \u0111\u01b0\u1ee3c x\u00e1c nh\u1eadn b\u1eb1ng v\u0103n b\u1ea3n tr\u01b0\u1edbc khi ph\u00e1t h\u00e0nh.<\/p>\n

\"S\u1ea3n<\/p>\n

So s\u00e1nh cho m\u1ed9t th\u00f4ng s\u1ed1 k\u1ef9 thu\u1eadt c\u00f3 t\u00ednh b\u1ea3o v\u1ec7<\/h2>\n\n\n\n\n\n\n\n
K\u00edch th\u01b0\u1edbc<\/th>\nL\u1ef1a ch\u1ecdn A<\/th>\nPh\u01b0\u01a1ng \u00e1n B<\/th>\n<\/tr>\n<\/thead>\n
T\u1ea3i<\/td>\nY\u00eau c\u1ea7u t\u00ednh to\u00e1n l\u00e0 bao nhi\u00eau?<\/td>\nBi\u1ec3n hi\u1ec7u v\u00e0 chu k\u1ef3 l\u00e0m vi\u1ec7c<\/td>\n<\/tr>\n
Ng\u01b0\u1eddi \u0111i\u1ec1u khi\u1ec3n<\/td>\nLi\u1ec7u n\u00f3 c\u00f3 th\u1ec3 truy\u1ec1n t\u1ea3i d\u00f2ng \u0111i\u1ec7n \u0111\u01b0\u1ee3c b\u1ea3o v\u1ec7 kh\u00f4ng?<\/td>\n\u0110\u1ed9 c\u00f4ng su\u1ea5t v\u00e0 gi\u1edbi h\u1ea1n t\u1ea3i<\/td>\n<\/tr>\n
\u0110\u01b0\u1eddng cong<\/td>\nC\u00f3 d\u1ef1 ki\u1ebfn t\u00ecnh tr\u1ea1ng qu\u00e1 t\u1ea3i kh\u00f4ng?<\/td>\nTh\u00f4ng tin v\u1ec1 thi\u1ebft b\u1ecb v\u00e0 \u0111\u01b0\u1eddng cong th\u1eddi gian-hi\u1ec7u su\u1ea5t<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

C\u00e1c ho\u1ea1t \u0111\u1ed9ng l\u1ef1a ch\u1ecdn v\u00e0 mua s\u1eafm<\/h2>\n
    \n
  1. \u0110\u00f3ng b\u0103ng c\u00e1c gi\u1ea3 \u0111\u1ecbnh v\u1ec1 \u0111i\u1ec7n: \u0111i\u1ec7n \u00e1p h\u1ec7 th\u1ed1ng, s\u1ed1 c\u1ef1c, d\u00f2ng t\u1ea3i, ph\u01b0\u01a1ng ph\u00e1p d\u1eabn \u0111i\u1ec7n, d\u00f2ng s\u1ef1 c\u1ed1 v\u00e0 gi\u1edbi h\u1ea1n nhi\u1ec7t \u0111\u1ed9 m\u00f4i tr\u01b0\u1eddng.<\/li>\n
  2. Y\u00eau c\u1ea7u d\u1eef li\u1ec7u theo d\u00f2ng s\u1ea3n ph\u1ea9m: phi\u00ean b\u1ea3n ti\u00eau chu\u1ea9n, \u0111\u01b0\u1eddng \u0111\u1eb7c t\u00ednh d\u00f2ng c\u1eaft, kh\u1ea3 n\u0103ng ng\u1eaft, gi\u1edbi h\u1ea1n c\u1ef1c \u0111\u1ea5u d\u00e2y, k\u00edch th\u01b0\u1edbc v\u00e0 b\u1eb1ng ch\u1ee9ng th\u1eed nghi\u1ec7m.<\/li>\n
  3. Xem x\u00e9t vi\u1ec7c ph\u1ed1i h\u1ee3p v\u1edbi c\u00e1c thi\u1ebft b\u1ecb th\u01b0\u1ee3ng ngu\u1ed3n v\u00e0 h\u1ea1 ngu\u1ed3n; kh\u00f4ng suy lu\u1eadn t\u00ednh ch\u1ecdn l\u1ecdc t\u1eeb nh\u00e3n hi\u1ec7u ho\u1eb7c k\u00edch th\u01b0\u1edbc khung.<\/li>\n
  4. Ph\u00ea duy\u1ec7t m\u1eabu ho\u1eb7c b\u00e0i vi\u1ebft \u0111\u1ea7u ti\u00ean, ghi l\u1ea1i l\u1ef1c si\u1ebft v\u00e0 c\u00e1c \u0111i\u1ec3m ki\u1ec3m tra, \u0111\u1ed3ng th\u1eddi x\u00e1c \u0111\u1ecbnh ai l\u00e0 ng\u01b0\u1eddi th\u1ef1c hi\u1ec7n c\u00e1c b\u00e0i ki\u1ec3m tra ch\u1ea1y th\u1eed.<\/li>\n
  5. L\u1eadp k\u1ebf ho\u1ea1ch ph\u1ee5 t\u00f9ng v\u00e0 qu\u1ea3n l\u00fd thay \u0111\u1ed5i \u0111\u1ec3 vi\u1ec7c thay th\u1ebf sau n\u00e0y kh\u00f4ng l\u00e0m thay \u0111\u1ed5i \u00e2m th\u1ea7m hi\u1ec7u su\u1ea5t an to\u00e0n.<\/li>\n<\/ol>\n

    \u0110\u1ed1i v\u1edbi nh\u1eefng ng\u01b0\u1eddi mua \u0111ang so s\u00e1nh c\u00e1c d\u00f2ng s\u1ea3n ph\u1ea9m b\u1ea3o v\u1ec7 c\u00f3 th\u1ec3 c\u1ea5u h\u00ecnh, CHAC Electric cung c\u1ea5p th\u00f4ng tin c\u00f4ng khai v\u1ec1 C\u00e1c s\u1ea3n ph\u1ea9m MCB<\/strong><\/a> v\u00e0 thi\u1ebft b\u1ecb ph\u00e2n ph\u1ed1i \u0111i\u1ec7n<\/strong><\/a>. H\u00e3y coi c\u00e1c trang n\u00e0y l\u00e0 \u0111i\u1ec3m kh\u1edfi \u0111\u1ea7u v\u00e0 x\u00e1c nh\u1eadn d\u1eef li\u1ec7u m\u00f4 h\u00ecnh ch\u00ednh x\u00e1c cho d\u1ef1 \u00e1n c\u1ee7a b\u1ea1n.<\/p>\n

    <\/p>\n

    S\u1eed d\u1ee5ng 20A l\u00e0m k\u1ebft qu\u1ea3 thi\u1ebft k\u1ebf, kh\u00f4ng ph\u1ea3i l\u00e0 m\u1ed9t gi\u1ea3 \u0111\u1ecbnh ban \u0111\u1ea7u<\/h2>\n

    A B\u1ed9 ph\u1eadn ng\u1eaft m\u1ea1ch 20 amp MCB<\/strong><\/a> ph\u1ea3i tu\u00e2n th\u1ee7 l\u1ecbch tr\u00ecnh t\u1ea3i, c\u00f4ng su\u1ea5t d\u00e2y d\u1eabn v\u00e0 ph\u01b0\u01a1ng ph\u00e1p l\u1eafp \u0111\u1eb7t. \u0110\u1ed1i v\u1edbi K\u00edch th\u01b0\u1edbc m\u1ea1ch nh\u00e1nh<\/strong><\/a>, H\u00e3y ki\u1ec3m tra c\u00e1c quy t\u1eafc t\u1ea3i li\u00ean t\u1ee5c, gi\u1ea3m c\u00f4ng su\u1ea5t khi m\u00f4i tr\u01b0\u1eddng xung quanh thay \u0111\u1ed5i v\u00e0 hi\u1ec7n t\u1ea1i qu\u00e1 d\u00f2ng tr\u01b0\u1edbc khi coi 20A l\u00e0 m\u1eb7c \u0111\u1ecbnh. Ti\u00eau ch\u00ed th\u1ee9 ba l\u00e0 C\u00f4ng su\u1ea5t d\u1eabn \u0111i\u1ec7n c\u1ee7a d\u00e2y d\u1eabn<\/strong>: C\u00f4ng t\u1eafc b\u1ea3o v\u1ec7 h\u1ec7 th\u1ed1ng d\u00e2y \u0111i\u1ec7n, kh\u00f4ng ch\u1ec9 l\u00e0 t\u1ea5m danh thi\u1ebfp c\u1ee7a thi\u1ebft b\u1ecb.<\/p>\n

    C\u00e1c c\u00e2u h\u1ecfi li\u00ean quan c\u1ee7a Google th\u01b0\u1eddng \u0111\u1ec1 c\u1eadp \u0111\u1ebfn c\u00e1c quy t\u1eafc v\u1ec1 vi\u1ec7c s\u1eed d\u1ee5ng c\u00f4ng t\u1eafc \u0111i\u1ec7n lo\u1ea1i 80% v\u00e0 125%. C\u00e1c quy t\u1eafc n\u00e0y ph\u1ee5 thu\u1ed9c v\u00e0o th\u1ea9m quy\u1ec1n v\u00e0 \u1ee9ng d\u1ee5ng, v\u00ec v\u1eady h\u00e3y n\u00eau r\u00f5 ti\u00eau chu\u1ea9n v\u00e0 c\u01a1 s\u1edf t\u00ednh to\u00e1n \u0111\u00e3 \u0111\u01b0\u1ee3c th\u00f4ng qua thay v\u00ec \u0111\u01b0a ra m\u1ed9t t\u1ef7 l\u1ec7 ph\u1ea7n tr\u0103m chung chung.<\/p>\n

    B\u00e0i vi\u1ebft li\u00ean quan: C\u00e1ch L\u1eadp K\u1ebf Ho\u1ea1ch Cho Gi\u1ea3i Ph\u00e1p C\u1ea7u Ch\u00ec T\u1ed5ng v\u00e0 T\u1ee7 \u0110i\u1ec7n D\u00e2n D\u1ee5ng<\/a> cho th\u1ea5y c\u00e1ch m\u00e0 l\u1ecbch bi\u1ec3u t\u1ea3i t\u1ea3i v\u00e0o \u0111\u01b0\u1ee3c t\u00ednh v\u00e0o trong b\u1ea3ng x\u1ebfp h\u1ea1ng cu\u1ed1i c\u00f9ng.<\/p>\n

    C\u00e1c c\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p<\/h2>\n

    M\u1ed9t MCB 20 A c\u00f3 th\u1ec3 cung c\u1ea5p \u0111\u01b0\u1ee3c nh\u1eefng g\u00ec?<\/h3>\n

    N\u00f3 c\u00f3 th\u1ec3 b\u1ea3o v\u1ec7 m\u1ed9t h\u1ec7 th\u1ed1ng ph\u00e2n ph\u1ed1i nh\u00e1nh c\u00f3 k\u00edch th\u01b0\u1edbc ph\u00f9 h\u1ee3p, trong \u0111\u00f3 nhu c\u1ea7u \u0111\u01b0\u1ee3c t\u00ednh to\u00e1n v\u00e0 c\u00f4ng su\u1ea5t thi\u1ebft b\u1ecb \u0111\u00e1p \u1ee9ng \u0111\u01b0\u1ee3c. Thi\u1ebft b\u1ecb \u0111\u01b0\u1ee3c k\u1ebft n\u1ed1i, ph\u01b0\u01a1ng ph\u00e1p d\u1eabn v\u00e0 m\u00e3 \u0111\u1ecba ph\u01b0\u01a1ng s\u1ebd x\u00e1c \u0111\u1ecbnh t\u1ea3i tr\u1ecdng th\u1ef1c t\u1ebf.<\/p>\n

    K\u00edch th\u01b0\u1edbc d\u00e2y \u0111i\u1ec7n n\u00e0o \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng v\u1edbi b\u1ed9 ng\u1eaft \u0111i\u1ec7n 20 A?<\/h3>\n

    K\u00edch th\u01b0\u1edbc d\u00e2y \u0111i\u1ec7n ph\u1ee5 thu\u1ed9c v\u00e0o v\u1eadt li\u1ec7u d\u1eabn \u0111i\u1ec7n, l\u1edbp c\u00e1ch \u0111i\u1ec7n, nhi\u1ec7t \u0111\u1ed9 m\u00f4i tr\u01b0\u1eddng xung quanh, ph\u01b0\u01a1ng ph\u00e1p l\u1eafp \u0111\u1eb7t v\u00e0 quy chu\u1ea9n k\u1ef9 thu\u1eadt. N\u00ean s\u1eed d\u1ee5ng b\u1ea3ng th\u00f4ng s\u1ed1 ampacity \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh k\u00edch th\u01b0\u1edbc d\u00e2y \u0111i\u1ec7n thay v\u00ec \u00e1p d\u1ee5ng quy t\u1eafc chung chung.<\/p>\n

    M\u1ed9t MCB c\u00f3 c\u00f4ng su\u1ea5t 20 A c\u00f3 ph\u1ea3i l\u00e0 lo\u1ea1i B hay C?<\/h3>\n

    H\u00e3y ch\u1ecdn d\u1ef1a tr\u00ean c\u00f4ng su\u1ea5t \u0111\u1ea7u v\u00e0o v\u00e0 vi\u1ec7c c\u1ea7n gi\u1ea3i quy\u1ebft s\u1ef1 c\u1ed1. \u0110\u00e8n chi\u1ebfu s\u00e1ng v\u00e0 c\u00e1c thi\u1ebft b\u1ecb ti\u00eau d\u00f9ng th\u00f4ng th\u01b0\u1eddng c\u00f3 th\u1ec3 ph\u00f9 h\u1ee3p v\u1edbi lo\u1ea1i B; c\u00e1c thi\u1ebft b\u1ecb c\u00f3 d\u00f2ng \u0111i\u1ec7n kh\u1edfi \u0111\u1ed9ng cao h\u01a1n c\u00f3 th\u1ec3 c\u1ea7n lo\u1ea1i C n\u1ebfu \u0111i\u1ec1u ki\u1ec7n h\u01b0 h\u1ecfng cho ph\u00e9p.<\/p>\n

    C\u00f3 th\u1ec3 s\u1eed d\u1ee5ng MCB 20 A th\u01b0\u01a1ng m\u1ea1i kh\u00f4ng?<\/h3>\n

    V\u00e2ng, khi thi\u1ebft b\u1ecb, b\u1ea3ng m\u1ea1ch, ph\u1ed1i h\u1ee3p v\u00e0 h\u1ec7 th\u1ed1ng d\u00e2y \u0111i\u1ec7n tu\u00e2n th\u1ee7 c\u00e1c y\u00eau c\u1ea7u l\u1eafp \u0111\u1eb7t th\u01b0\u01a1ng m\u1ea1i v\u00e0 quy \u0111\u1ecbnh c\u1ee7a \u0111\u1ecba \u0111i\u1ec3m s\u1eed d\u1ee5ng.<\/p>\n

    T\u00e0i li\u1ec7u tham kh\u1ea3o c\u00f3 th\u1ea9m quy\u1ec1n<\/h2>\n