{"id":2406,"date":"2026-08-18T11:00:00","date_gmt":"2026-08-18T11:00:00","guid":{"rendered":"https:\/\/lbajiele.com\/?p=2406"},"modified":"2026-09-23T09:59:23","modified_gmt":"2026-09-23T09:59:23","slug":"complete-guide-to-electrical-calculations-conversions","status":"publish","type":"post","link":"https:\/\/lbajiele.com\/vi\/blog\/complete-guide-to-electrical-calculations-conversions\/","title":{"rendered":"H\u01b0\u1edbng d\u1eabn to\u00e0n di\u1ec7n v\u1ec1 T\u00ednh to\u00e1n &amp; Chuy\u1ec3n \u0111\u1ed5i \u0110i\u1ec7n"},"content":{"rendered":"<p><strong>Chuy\u1ec3n \u0111\u1ed5i kVA sang ampe<\/strong> l\u00e0 m\u1ed9t trong nh\u1eefng ph\u00e9p t\u00ednh ph\u1ed5 bi\u1ebfn nh\u1ea5t trong vi\u1ec7c l\u1ef1a ch\u1ecdn m\u00e1y bi\u1ebfn \u00e1p, m\u00e1y ph\u00e1t \u0111i\u1ec7n, c\u00e1p \u0111i\u1ec7n v\u00e0 thi\u1ebft b\u1ecb \u0111\u00f3ng c\u1eaft. Ph\u00e9p t\u00ednh n\u00e0y r\u1ea5t \u0111\u01a1n gi\u1ea3n, nh\u01b0ng k\u1ebft qu\u1ea3 ch\u1ec9 ch\u00ednh x\u00e1c khi th\u1ee9 t\u1ef1 pha v\u00e0 \u0111i\u1ec7n \u00e1p \u0111\u01b0\u1ee3c nh\u1eadp \u0111\u00fang. H\u01b0\u1edbng d\u1eabn n\u00e0y cung c\u1ea5p c\u00e1c c\u00f4ng th\u1ee9c cho d\u00f2ng \u0111i\u1ec7n m\u1ed9t pha v\u00e0 ba pha, c\u00e1c v\u00ed d\u1ee5 c\u00f3 l\u1eddi gi\u1ea3i t\u1eeb 15 kVA \u0111\u1ebfn 75 kVA, c\u00e1ch chuy\u1ec3n \u0111\u1ed5i ng\u01b0\u1ee3c t\u1eeb ampe sang kVA, v\u00e0 c\u00e1c b\u01b0\u1edbc ki\u1ec3m tra th\u1ef1c t\u1ebf c\u1ea7n thi\u1ebft tr\u01b0\u1edbc khi s\u1eed d\u1ee5ng d\u00f2ng \u0111i\u1ec7n \u0111\u00e3 t\u00ednh l\u00e0m \u0111\u1ecbnh m\u1ee9c thi\u1ebft b\u1ecb.<\/p>\n\n<h2>kVA c\u00f3 ngh\u0129a l\u00e0 g\u00ec?<\/h2>\n<p>kVA l\u00e0 vi\u1ebft t\u1eaft c\u1ee7a kilovolt-amperes v\u00e0 \u0111o c\u00f4ng su\u1ea5t bi\u1ec3u ki\u1ebfn. M\u1ed9t kVA b\u1eb1ng 1.000 volt-ampere. C\u00f4ng su\u1ea5t bi\u1ec3u ki\u1ebfn bao g\u1ed3m ph\u1ea7n \u0111\u01b0\u1ee3c chuy\u1ec3n \u0111\u1ed5i th\u00e0nh c\u00f4ng c\u00f3 \u00edch v\u00e0 ph\u1ea7n ph\u1ea3n kh\u00e1ng \u0111\u01b0\u1ee3c trao \u0111\u1ed5i b\u1edfi c\u00e1c t\u1ea3i c\u1ea3m \u1ee9ng ho\u1eb7c \u0111i\u1ec7n dung. M\u00e1y bi\u1ebfn \u00e1p v\u00e0 m\u00e1y ph\u00e1t \u0111i\u1ec7n th\u01b0\u1eddng \u0111\u01b0\u1ee3c \u0111\u1ecbnh m\u1ee9c theo kVA v\u00ec s\u1ef1 n\u00f3ng l\u00ean c\u1ee7a ch\u00fang ch\u1ee7 y\u1ebfu li\u00ean quan \u0111\u1ebfn \u0111i\u1ec7n \u00e1p v\u00e0 d\u00f2ng \u0111i\u1ec7n, ch\u1ee9 kh\u00f4ng ch\u1ec9 ri\u00eang h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t c\u1ee7a t\u1ea3i.<\/p>\n<p>kW \u0111o l\u01b0\u01a1\u0300ng c\u00f4ng su\u1ea5t th\u1ef1c. \u0110\u1ed1i v\u1edbi t\u1ea3i c\u00e2n b\u1eb1ng, m\u1ed1i quan h\u1ec7 l\u00e0 <strong>kW = kVA \u00d7 h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t<\/strong>. T\u1ea3i tr\u1ecdng 100 kVA \u1edf h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t 0,8 ti\u00eau th\u1ee5 80 kW c\u00f4ng su\u1ea5t t\u00e1c d\u1ee5ng. Kh\u00f4ng coi kVA v\u00e0 kW l\u00e0 b\u1eb1ng nhau tr\u1eeb khi h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t b\u1eb1ng 1,0.<\/p>\n\n<h2>C\u00f4ng th\u1ee9c t\u00ednh kVA sang Ampe m\u1ed9t pha<\/h2>\n<p>\u0110\u1ed1i v\u1edbi m\u1ea1ch \u0111i\u1ec7n xoay chi\u1ec1u m\u1ed9t pha:<\/p>\n<p><strong>C\u01b0\u1eddng \u0111\u1ed9 d\u00f2ng \u0111i\u1ec7n (A) = kVA \u00d7 1.000 \u00f7 \u0110i\u1ec7n \u00e1p (V)<\/strong><\/p>\n<p>V\u00ed d\u1ee5: m\u1ed9t m\u00e1y bi\u1ebfn \u00e1p m\u1ed9t pha 25 kVA v\u1edbi cu\u1ed9n th\u1ee9 c\u1ea5p 240 V cung c\u1ea5p:<\/p>\n<p><strong>25 \u00d7 1.000 \u00f7 240 = 104,2 A<\/strong><\/p>\n<p>\u1ede m\u1ee9c \u0111i\u1ec7n \u00e1p 480 V, m\u1ee9c 25 kVA t\u01b0\u01a1ng \u0111\u01b0\u01a1ng v\u1edbi 52,1 A. \u0110i\u1ec1u n\u00e0y minh h\u1ecda l\u00fd do t\u1ea1i sao m\u1ed9t gi\u00e1 tr\u1ecb kVA kh\u00f4ng th\u1ec3 \u0111\u01b0\u1ee3c chuy\u1ec3n \u0111\u1ed5i th\u00e0nh ampe n\u1ebfu kh\u00f4ng bi\u1ebft \u0111i\u1ec7n \u00e1p.<\/p>\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/lbajiele.com\/wp-content\/uploads\/2026\/08\/single-phase-kva-to-amps.png\" alt=\"Single-phase transformer and distribution panel used for kVA to amps calculation\"\/><figcaption>\u0110\u1ed1i v\u1edbi h\u1ec7 th\u1ed1ng m\u1ed9t pha, d\u00f2ng \u0111i\u1ec7n ph\u1ee5 thu\u1ed9c v\u00e0o c\u00f4ng su\u1ea5t bi\u1ec3u ki\u1ebfn v\u00e0 \u0111i\u1ec7n \u00e1p \u0111\u01b0\u1eddng d\u00e2y.<\/figcaption><\/figure>\n\n<h2>C\u00f4ng th\u1ee9c t\u00ednh kVA sang Ampe ba pha<\/h2>\n<p>\u0110\u1ed1i v\u1edbi m\u1ea1ch ba pha c\u00e2n b\u1eb1ng s\u1eed d\u1ee5ng \u0111i\u1ec7n \u00e1p d\u00e2y:<\/p>\n<p><strong>C\u01b0\u1eddng \u0111\u1ed9 d\u00f2ng \u0111i\u1ec7n (A) = kVA \u00d7 1.000 \u00f7 (\u221a3 \u00d7 \u0110i\u1ec7n \u00e1p)<\/strong><\/p>\n<p>V\u00ec \u221a3 x\u1ea5p x\u1ec9 1,732, m\u00e1y bi\u1ebfn \u00e1p ba pha 75 kVA \u1edf \u0111i\u1ec7n \u00e1p 400 V cung c\u1ea5p:<\/p>\n<p><strong>75 \u00d7 1.000 \u00f7 (1,732 \u00d7 400) = 108,3 A<\/strong><\/p>\n<p>\u1ede m\u1ee9c \u0111i\u1ec7n \u00e1p 480 V, c\u00f9ng c\u00f4ng su\u1ea5t 75 kVA n\u00e0y cung c\u1ea5p kho\u1ea3ng 90,2 A. C\u00f4ng th\u1ee9c n\u00e0y gi\u1ea3 \u0111\u1ecbnh m\u1ed9t t\u1ea3i ba pha \u0111\u1ed1i x\u1ee9ng. S\u1ef1 m\u1ea5t c\u00e2n b\u1eb1ng pha \u0111\u00e1ng k\u1ec3 \u0111\u00f2i h\u1ecfi ph\u1ea3i xem x\u00e9t d\u00f2ng \u0111i\u1ec7n theo t\u1eebng pha v\u00e0 c\u00f3 th\u1ec3 l\u00e0m h\u1ea1n ch\u1ebf c\u00f4ng su\u1ea5t kh\u1ea3 d\u1ee5ng c\u1ee7a m\u00e1y bi\u1ebfn \u00e1p.<\/p>\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/lbajiele.com\/wp-content\/uploads\/2026\/08\/three-phase-kva-to-amps.png\" alt=\"Three-phase transformer and industrial switchboard for electrical current calculations\"\/><figcaption>Vi\u1ec7c chuy\u1ec3n \u0111\u1ed5i ba pha s\u1eed d\u1ee5ng \u0111i\u1ec7n \u00e1p gi\u1eefa c\u00e1c d\u00e2y pha v\u00e0 c\u0103n b\u1eadc hai c\u1ee7a ba.<\/figcaption><\/figure>\n\n<h2>C\u00e1c v\u00ed d\u1ee5 nhanh v\u1ec1 chuy\u1ec3n \u0111\u1ed5i kVA sang Ampe<\/h2>\n<table><thead><tr><th>C\u00f4ng su\u1ea5t \u0111\u1ecbnh m\u1ee9c c\u1ee7a m\u00e1y bi\u1ebfn \u00e1p<\/th><th>1 pha 240 V<\/th><th>Ba pha 400 V<\/th><th>3 pha 480 V<\/th><\/tr><\/thead><tbody>\n<tr><td>15 kVA<\/td><td>62,5 A<\/td><td>21.7 A<\/td><td>18,0 A<\/td><\/tr>\n<tr><td>25 kVA<\/td><td>104.2 A<\/td><td>36.1 A<\/td><td>30.1 A<\/td><\/tr>\n<tr><td>30 kVA<\/td><td>125,0 A<\/td><td>43.3 A<\/td><td>36.1 A<\/td><\/tr>\n<tr><td>45 kVA<\/td><td>187,5 A<\/td><td>65,0 A<\/td><td>54.1 A<\/td><\/tr>\n<tr><td>75 kVA<\/td><td>312,5 A<\/td><td>108.3 A<\/td><td>90,2 A<\/td><\/tr>\n<\/tbody><\/table>\n<p>C\u00e1c gi\u00e1 tr\u1ecb n\u00e0y l\u00e0 d\u00f2ng \u0111i\u1ec7n \u0111\u1ea7y t\u1ea3i \u0111\u01b0\u1ee3c t\u00ednh to\u00e1n, kh\u00f4ng ph\u1ea3i l\u1ef1a ch\u1ecdn c\u00e1p ho\u1eb7c c\u1ea7u dao t\u1ef1 \u0111\u1ed9ng. C\u00e1c quy \u0111\u1ecbnh v\u1ec1 \u0111i d\u00e2y c\u00f3 th\u1ec3 y\u00eau c\u1ea7u h\u1ec7 s\u1ed1 d\u00f2ng \u0111i\u1ec7n li\u00ean t\u1ee5c, h\u1ec7 s\u1ed1 hi\u1ec7u ch\u1ec9nh v\u00e0 k\u00edch th\u01b0\u1edbc thi\u1ebft b\u1ecb b\u1ea3o v\u1ec7 ti\u00eau chu\u1ea9n. D\u00f2ng \u0111i\u1ec7n kh\u1edfi \u0111\u1ed9ng c\u1ee7a m\u00e1y bi\u1ebfn \u00e1p v\u00e0 ph\u1ed1i h\u1ee3p ng\u1eafn m\u1ea1ch c\u0169ng \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn vi\u1ec7c l\u1ef1a ch\u1ecdn c\u1ea7u dao.<\/p>\n\n<h2>C\u00e1ch chuy\u1ec3n \u0111\u1ed5i Ampe sang kVA<\/h2>\n<p>\u0110\u1ea3o ng\u01b0\u1ee3c c\u00e1c c\u00f4ng th\u1ee9c khi bi\u1ebft d\u00f2ng \u0111i\u1ec7n v\u00e0 \u0111i\u1ec7n \u00e1p:<\/p>\n<ul>\n  <li><strong>M\u1ed9t pha: kVA = V\u00f4n \u00d7 Ampe \u00f7 1.000<\/strong><\/li>\n  <li><strong>Ba pha: kVA = \u221a3 \u00d7 V\u00f4n \u00d7 Ampe \u00f7 1.000<\/strong><\/li>\n<\/ul>\n<p>V\u00ed d\u1ee5: m\u1ed9t t\u1ea3i ba pha \u0111\u1ed1i x\u1ee9ng ti\u00eau th\u1ee5 200 A \u1edf \u0111i\u1ec7n \u00e1p 400 V:<\/p>\n<p><strong>1,732 \u00d7 400 \u00d7 200 \u00f7 1.000 = 138,6 kVA<\/strong><\/p>\n<p>N\u1ebfu h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t \u0111o \u0111\u01b0\u1ee3c l\u00e0 0,85, c\u00f4ng su\u1ea5t t\u00e1c d\u1ee5ng x\u1ea5p x\u1ec9 l\u00e0 138,6 \u00d7 0,85 = 117,8 kW. C\u00e1c ph\u00e9p \u0111o ph\u1ea3i bao g\u1ed3m c\u00e1c \u0111i\u1ec1u ki\u1ec7n v\u1eadn h\u00e0nh \u0111\u1ea1i di\u1ec7n; m\u1ed9t l\u1ea7n \u0111\u1ecdc ng\u1eafn c\u00f3 th\u1ec3 b\u1ecf s\u00f3t nhu c\u1ea7u c\u1ef1c \u0111\u1ea1i ho\u1eb7c t\u1ea3i ng\u1eaft qu\u00e3ng.<\/p>\n\n<h2>kVA, Watts v\u00e0 H\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t<\/h2>\n<p>\u0110\u1ed1i v\u1edbi h\u1ec7 th\u1ed1ng \u0111i\u1ec7n xoay chi\u1ec1u (AC), vi\u1ec7c chuy\u1ec3n \u0111\u1ed5i kVA sang watt \u0111\u00f2i h\u1ecfi h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t:<\/p>\n<p><strong>Watts = kVA \u00d7 1.000 \u00d7 h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t<\/strong><\/p>\n<p>\u0110\u1ec3 chuy\u1ec3n \u0111\u1ed5i watt sang kVA:<\/p>\n<p><strong>kVA = Watt \u00f7 (1.000 \u00d7 h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t)<\/strong><\/p>\n<p>T\u1ea3i tr\u1ecdng 50 kW \u1edf h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t 0,8 y\u00eau c\u1ea7u 62,5 kVA. \u1ede h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t 0,95, n\u00f3 y\u00eau c\u1ea7u 52,6 kVA. Vi\u1ec7c c\u1ea3i thi\u1ec7n h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t c\u00f3 th\u1ec3 l\u00e0m gi\u1ea3m d\u00f2ng \u0111i\u1ec7n tr\u00ean \u0111\u01b0\u1eddng d\u00e2y v\u00e0 gi\u1ea3i ph\u00f3ng c\u00f4ng su\u1ea5t, nh\u01b0ng c\u00e1c t\u1ee5 b\u00f9 ph\u1ea3i \u0111\u01b0\u1ee3c \u0111\u00e1nh gi\u00e1 v\u1ec1 s\u00f3ng h\u00e0i, c\u1ed9ng h\u01b0\u1edfng v\u00e0 qu\u00e1 \u0111\u1ed9 \u0111\u00f3ng c\u1eaft.<\/p>\n\n<h2>D\u00f2ng \u0111i\u1ec7n s\u01a1 c\u1ea5p v\u00e0 th\u1ee9 c\u1ea5p c\u1ee7a m\u00e1y bi\u1ebfn \u00e1p<\/h2>\n<p>M\u00e1y bi\u1ebfn \u00e1p c\u00f3 c\u00f4ng su\u1ea5t kVA x\u1ea5p x\u1ec9 nh\u01b0 nhau \u1edf c\u1ea3 hai ph\u00eda, ch\u01b0a t\u00ednh t\u1ed5n hao, nh\u01b0ng d\u00f2ng \u0111i\u1ec7n c\u1ee7a n\u00f3 thay \u0111\u1ed5i t\u1ec9 l\u1ec7 ngh\u1ecbch v\u1edbi \u0111i\u1ec7n \u00e1p. M\u1ed9t m\u00e1y bi\u1ebfn \u00e1p ba pha 1.000 kVA c\u00f3 cu\u1ed9n s\u01a1 c\u1ea5p 10 kV v\u00e0 cu\u1ed9n th\u1ee9 c\u1ea5p 400 V c\u00f3 d\u00f2ng \u0111i\u1ec7n \u0111\u1ea7y t\u1ea3i x\u1ea5p x\u1ec9 l\u00e0:<\/p>\n<ul>\n  <li>Ch\u00ednh: 1.000.000 \u00f7 (1,732 \u00d7 10.000) = 57,7 A<\/li>\n  <li>Th\u1ee9 c\u1ea5p: 1.000.000 \u00f7 (1,732 \u00d7 400) = 1.443 A<\/li>\n<\/ul>\n<p>Do \u0111\u00f3, t\u1ee7 \u0111i\u1ec7n h\u1ea1 th\u1ebf v\u00e0 c\u00e1c thanh d\u1eabn \u0111i\u1ec7n mang d\u00f2ng \u0111i\u1ec7n l\u1edbn h\u01a1n r\u1ea5t nhi\u1ec1u so v\u1edbi thi\u1ebft b\u1ecb ch\u00ednh trung th\u1ebf. LBAJI's <a href=\"https:\/\/lbajiele.com\/vi\/san-pham\/35kv-oil-immersed-power-transformer\/\">M\u00e1y bi\u1ebfn \u00e1p ng\u00e2m d\u1ea7u 35 kV<\/a> c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c c\u1ea5u h\u00ecnh cho c\u00e1c x\u1ebfp h\u1ea1ng d\u00e0nh ri\u00eang cho d\u1ef1 \u00e1n, trong khi c\u00e1c d\u1ef1 \u00e1n \u0111\u00f3ng g\u00f3i c\u00f3 th\u1ec3 t\u00edch h\u1ee3p thi\u1ebft b\u1ecb m\u00e1y bi\u1ebfn \u00e1p v\u00e0 ph\u00e2n ph\u1ed1i v\u00e0o m\u1ed9t <a href=\"https:\/\/lbajiele.com\/vi\/san-pham\/ybm-12-high-and-low-voltage-preinstalled-substation\/\">Tr\u1ea1m bi\u1ebfn \u00e1p l\u1eafp gh\u00e9p s\u1eb5n YBM-12<\/a>.<\/p>\n\n<h2>T\u1eeb T\u1ea3i T\u00ednh To\u00e1n \u0110\u1ebfn K\u00edch Th\u01b0\u1edbc M\u00e1y Bi\u1ebfn \u00c1p<\/h2>\n<p>Vi\u1ec7c c\u1ed9ng th\u00eam m\u1ecdi c\u00f4ng su\u1ea5t \u0111\u1ecbnh m\u1ee9c (kW) tr\u00ean nh\u00e3n th\u01b0\u1eddng l\u00e0m ph\u00f3ng \u0111\u1ea1i nhu c\u1ea7u b\u00ecnh th\u01b0\u1eddng, trong khi ch\u1ec9 s\u1eed d\u1ee5ng t\u1ea3i \u0111o \u0111\u01b0\u1ee3c trung b\u00ecnh c\u00f3 th\u1ec3 \u0111\u00e1nh gi\u00e1 th\u1ea5p c\u00e1c \u0111\u1ec9nh t\u1ea3i. M\u1ed9t b\u1ea3ng bi\u1ec3u t\u1ea3i c\u00f3 th\u1ec3 b\u1ea3o v\u1ec7 \u0111\u01b0\u1ee3c s\u1ebd t\u00e1ch bi\u1ec7t c\u00e1c ph\u1ee5 t\u1ea3i li\u00ean t\u1ee5c, gi\u00e1n \u0111o\u1ea1n, d\u1ef1 ph\u00f2ng, \u0111\u1ed9ng c\u01a1, phi tuy\u1ebfn t\u00ednh v\u00e0 ph\u1ee5 t\u1ea3i trong t\u01b0\u01a1ng lai. \u00c1p d\u1ee5ng c\u00e1c h\u1ec7 s\u1ed1 nhu c\u1ea7u v\u00e0 h\u1ec7 s\u1ed1 \u0111a d\u1ea1ng \u0111\u00e3 \u0111\u01b0\u1ee3c t\u00e0i li\u1ec7u h\u00f3a, quy \u0111\u1ed5i c\u00f4ng su\u1ea5t t\u00e1c d\u1ee5ng th\u00e0nh kVA v\u1edbi c\u00e1c h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t th\u1ef1c t\u1ebf, \u0111\u1ed3ng th\u1eddi ki\u1ec3m tra ch\u1ebf \u0111\u1ed9 kh\u1edfi \u0111\u1ed9ng ho\u1eb7c ch\u1ebf \u0111\u1ed9 l\u00e0m vi\u1ec7c theo chu k\u1ef3.<\/p>\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/lbajiele.com\/wp-content\/uploads\/2026\/08\/transformer-load-sizing-calculation.png\" alt=\"Calculator and load documents beside electrical equipment for transformer sizing\"\/><figcaption>L\u1ecbch tr\u00ecnh m\u00e1y bi\u1ebfn \u00e1p ph\u1ea3i t\u00ednh \u0111\u1ebfn nhu c\u1ea7u, \u0111\u1ed9 \u0111a d\u1ea1ng, th\u1eddi gian kh\u1edfi \u0111\u1ed9ng \u0111\u1ed9ng c\u01a1 v\u00e0 c\u00f4ng su\u1ea5t trong t\u01b0\u01a1ng lai.<\/figcaption><\/figure>\n\n<p>Sau khi ch\u1ecdn m\u1ee9c c\u00f4ng su\u1ea5t kVA ti\u00eau chu\u1ea9n s\u01a1 b\u1ed9, h\u00e3y x\u00e1c minh:<\/p>\n<ul>\n  <li>h\u1ed3 s\u01a1 t\u1ea3i th\u00f4ng th\u01b0\u1eddng v\u00e0 kh\u1ea9n c\u1ea5p;<\/li>\n  <li>nhi\u1ec7t \u0111\u1ed9 m\u00f4i tr\u01b0\u1eddng, \u0111\u1ed9 cao v\u00e0 ph\u01b0\u01a1ng ph\u00e1p l\u00e0m m\u00e1t;<\/li>\n  <li>s\u1ee5t \u00e1p khi kh\u1edfi \u0111\u1ed9ng \u0111\u1ed9ng c\u01a1;<\/li>\n  <li>hi\u1ec7u \u1ee9ng nhi\u1ec7t \u0111i\u1ec1u h\u00f2a t\u1eeb b\u1ed9 chuy\u1ec3n \u0111\u1ed5i, h\u1ec7 th\u1ed1ng UPS v\u00e0 t\u1ea3i \u0111\u00e8n LED;<\/li>\n  <li>m\u1edf r\u1ed9ng trong t\u01b0\u01a1ng lai v\u00e0 v\u1eadn h\u00e0nh song song;<\/li>\n  <li>d\u00f2ng ng\u1eafn m\u1ea1ch kh\u1ea3 d\u1ee5ng \u1edf ph\u00eda th\u1ee9 c\u1ea5p;<\/li>\n  <li>Ph\u1ed1i h\u1ee3p b\u1ea3o v\u1ec7 th\u01b0\u1ee3ng ngu\u1ed3n v\u00e0 h\u1ea1 ngu\u1ed3n.<\/li>\n<\/ul>\n\n<h2>Nh\u1eefng l\u1ed7i t\u00ednh to\u00e1n th\u01b0\u1eddng g\u1eb7p<\/h2>\n<ol>\n  <li><strong>S\u1eed d\u1ee5ng c\u00f4ng th\u1ee9c m\u1ed9t pha cho ba pha.<\/strong> Ph\u01b0\u01a1ng tr\u00ecnh ba pha y\u00eau c\u1ea7u \u221a3 khi s\u1eed d\u1ee5ng \u0111i\u1ec7n \u00e1p d\u00e2y v\u1edbi d\u00e2y.<\/li>\n  <li><strong>Nh\u1ea7m l\u1eabn gi\u1eefa kW v\u00e0 kVA.<\/strong> Bao g\u1ed3m h\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t khi chuy\u1ec3n \u0111\u1ed5i c\u00f4ng su\u1ea5t t\u00e1c d\u1ee5ng v\u00e0 c\u00f4ng su\u1ea5t bi\u1ec3u ki\u1ebfn.<\/li>\n  <li><strong>Nh\u1eadp sai \u0111i\u1ec7n \u00e1p.<\/strong> X\u00e1c nh\u1eadn xem b\u1ea3n v\u1ebd cung c\u1ea5p \u0111i\u1ec7n \u00e1p d\u00e2y-\u0111\u00e2y hay \u0111i\u1ec7n \u00e1p d\u00e2y-trung t\u00ednh.<\/li>\n  <li><strong>Xem d\u00f2ng \u0111i\u1ec7n t\u00ednh to\u00e1n nh\u01b0 k\u00edch th\u01b0\u1edbc c\u1ea7u dao.<\/strong> \u00c1p d\u1ee5ng ti\u00eau chu\u1ea9n \u0111i d\u00e2y hi\u1ec7n h\u00e0nh, ch\u1ebf \u0111\u1ed9 t\u1ea3i, d\u00f2ng kh\u1edfi \u0111\u1ed9ng v\u00e0 nghi\u00ean c\u1ee9u ph\u1ed1i h\u1ee3p b\u1ea3o v\u1ec7.<\/li>\n  <li><strong>B\u1ecf qua hi\u1ec7u su\u1ea5t.<\/strong> C\u00f4ng su\u1ea5t \u0111\u1ea7u v\u00e0o (kW) l\u1edbn h\u01a1n c\u00f4ng su\u1ea5t \u0111\u1ea7u ra (kW) do thi\u1ebft b\u1ecb c\u00f3 t\u1ed5n th\u1ea5t.<\/li>\n  <li><strong>B\u1ecf qua s\u00f3ng h\u00e0i v\u00e0 hi\u1ec7n t\u01b0\u1ee3ng m\u1ea5t c\u00e2n b\u1eb1ng.<\/strong> D\u00f2ng \u0111i\u1ec7n hi\u1ec7u d\u1ee5ng (RMS) v\u00e0 t\u1ea3i trung t\u00ednh c\u00f3 th\u1ec3 v\u01b0\u1ee3t qu\u00e1 \u01b0\u1edbc t\u00ednh c\u01a1 b\u1ea3n c\u00e2n b\u1eb1ng \u0111\u01a1n gi\u1ea3n.<\/li>\n<\/ol>\n\n<h2>\u00c1p d\u1ee5ng k\u1ebft qu\u1ea3 v\u00e0o vi\u1ec7c l\u1ef1a ch\u1ecdn thi\u1ebft b\u1ecb \u0111\u00f3ng c\u1eaft<\/h2>\n<p>D\u00f2ng \u0111i\u1ec7n to\u00e0n t\u1ea3i t\u00ednh to\u00e1n thi\u1ebft l\u1eadp m\u1ee9c y\u00eau c\u1ea7u d\u00f2ng \u0111i\u1ec7n li\u00ean t\u1ee5c t\u1ed1i thi\u1ec3u, nh\u01b0ng vi\u1ec7c l\u1ef1a ch\u1ecdn thi\u1ebft b\u1ecb \u0111\u00f3ng c\u1eaft c\u0169ng ph\u1ee5 thu\u1ed9c v\u00e0o m\u1ee9c s\u1ef1 c\u1ed1, \u0111\u1ecbnh m\u1ee9c c\u00e1ch \u0111i\u1ec7n, v\u1ecf b\u1ecdc, y\u00eau c\u1ea7u v\u1ec1 h\u1ed3 quang n\u1ed9i b\u1ed9 v\u00e0 ch\u1ebf \u0111\u1ed9 v\u1eadn h\u00e0nh. Ph\u00e2n ph\u1ed1i trung th\u1ebf c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng <a href=\"https:\/\/lbajiele.com\/vi\/san-pham\/kyn28a-12-armouring-removable-ac-metal-enclosed-switchgear\/\">T\u1ee7 \u0111i\u1ec7n c\u00f3 th\u1ec3 th\u00e1o r\u1eddi KYN28A-12<\/a>, trong khi c\u00e1c m\u1ea1ng v\u00f2ng nh\u1ecf g\u1ecdn c\u00f3 th\u1ec3 s\u1eed d\u1ee5ng <a href=\"https:\/\/lbajiele.com\/vi\/san-pham\/lbhb-12v-630-20-environmentally-friendly-gas-insulated-ring-main-unit\/\">T\u1ee7 RMU c\u00e1ch \u0111i\u1ec7n b\u1eb1ng kh\u00ed LBHB-12<\/a>. B\u1ea3ng danh m\u1ee5c thi\u1ebft b\u1ecb cu\u1ed1i c\u00f9ng n\u00ean \u0111\u01b0\u1ee3c \u0111\u1ed1i chi\u1ebfu v\u1edbi s\u01a1 \u0111\u1ed3 \u0111\u01a1n tuy\u1ebfn v\u00e0 nghi\u00ean c\u1ee9u s\u1ef1 c\u1ed1.<\/p>\n\n<div id=\"rank-math-faq\" class=\"rank-math-block\">\n<div class=\"rank-math-list\">\n<\/div>\n<\/div>\n\n\n<!-- lbaji-dataforseo-gaps:start -->\n<section class=\"lbaji-serp-gap\"><h2>Chuy\u1ec3n \u0111\u1ed5i m\u1ed9t pha sang ba pha<\/h2><p>D\u00f2ng \u0111i\u1ec7n m\u1ed9t pha b\u1eb1ng kVA \u00d7 1.000 \u00f7 v\u00f4n. D\u00f2ng \u0111i\u1ec7n ba pha b\u1eb1ng kVA \u00d7 1.000 \u00f7 (1,732 \u00d7 \u0111i\u1ec7n \u00e1p d\u00e2y v\u1edbi d\u00e2y). H\u1ec7 s\u1ed1 c\u0103n b\u1eadc hai c\u1ee7a ba l\u00e0 ngu\u1ed3n g\u00e2y l\u1ed7i ph\u1ed5 bi\u1ebfn nh\u1ea5t. H\u1ec7 s\u1ed1 c\u00f4ng su\u1ea5t l\u00e0 kh\u00f4ng c\u1ea7n thi\u1ebft khi \u0111\u00e3 bi\u1ebft kVA, nh\u01b0ng n\u00f3 l\u00e0 b\u1eaft bu\u1ed9c khi gi\u00e1 tr\u1ecb ban \u0111\u1ea7u l\u00e0 kW.<\/p><\/section>\n<section class=\"lbaji-serp-gap\"><h2>M\u1ed9t quy tr\u00ecnh m\u00e1y t\u00ednh \u0111\u00e1ng tin c\u1eady<\/h2><p>Ch\u1ecdn s\u1ed1 pha tr\u01b0\u1edbc, nh\u1eadp kVA v\u00e0 \u0111i\u1ec7n \u00e1p v\u1eadn h\u00e0nh th\u1ef1c t\u1ebf, t\u00ednh to\u00e1n kh\u00f4ng l\u00e0m tr\u00f2n s\u1edbm, v\u00e0 d\u00e1n nh\u00e3n xem k\u1ebft qu\u1ea3 l\u00e0 d\u00f2ng \u0111i\u1ec7n s\u01a1 c\u1ea5p hay th\u1ee9 c\u1ea5p. L\u1eb7p l\u1ea1i ph\u00e9p t\u00ednh \u1edf c\u1ea3 hai ph\u00eda c\u1ee7a m\u00e1y bi\u1ebfn \u00e1p. K\u1ebft qu\u1ea3 l\u00e0 d\u00f2ng \u0111i\u1ec7n \u0111\u1ea7y t\u1ea3i; kh\u1ea3 n\u0103ng mang d\u00f2ng c\u1ee7a d\u00e2y d\u1eabn, h\u1ec7 s\u1ed1 t\u1ea3i li\u00ean t\u1ee5c, suy gi\u1ea3m c\u00f4ng su\u1ea5t theo nhi\u1ec7t \u0111\u1ed9 xung quanh v\u00e0 quy t\u1eafc thi\u1ebft b\u1ecb b\u1ea3o v\u1ec7 \u0111\u00f2i h\u1ecfi c\u00e1c b\u01b0\u1edbc ki\u1ec3m tra ri\u00eang.<\/p><\/section>\n<!-- lbaji-dataforseo-gaps:end -->\n<!-- lbaji-references:start -->\n<section class=\"lbaji-technical-references\" aria-labelledby=\"technical-references-heading\">\n<h2 id=\"technical-references-heading\">T\u00e0i li\u1ec7u k\u1ef9 thu\u1eadt v\u00e0 \u0111\u1ecdc th\u00eam<\/h2>\n<p>C\u00e1c ngu\u1ed3n \u0111\u1ed9c l\u1eadp sau \u0111\u00e2y h\u1ed7 tr\u1ee3 c\u00e1c ti\u00eau chu\u1ea9n, thu\u1eadt ng\u1eef, ph\u00e9p t\u00ednh v\u00e0 b\u1ed1i c\u1ea3nh an to\u00e0n \u0111\u01b0\u1ee3c th\u1ea3o lu\u1eadn trong h\u01b0\u1edbng d\u1eabn n\u00e0y:<\/p>\n<ul><li><a href=\"https:\/\/www.nist.gov\/pml\/owm\/si-units-electric-current\" target=\"_blank\" rel=\"noopener nofollow\">C\u00e1c \u0111\u01a1n v\u1ecb SI c\u1ee7a NIST \u0111\u1ed1i v\u1edbi d\u00f2ng \u0111i\u1ec7n \u0111i\u1ec7n t\u1eed<\/a> \u2014 C\u00e1c \u0111\u1ecbnh ngh\u0129a c\u00f3 th\u1ea9m quy\u1ec1n v\u00e0 m\u1ed1i quan h\u1ec7 gi\u1eefa ampe, v\u00f4n, o\u00e1t v\u00e0 \u00f4m.<\/li>\n<li><a href=\"https:\/\/www.nist.gov\/pml\/special-publication-811\/nist-guide-si-appendix-b-conversion-factors\/nist-guide-si-appendix-b9\" target=\"_blank\" rel=\"noopener nofollow\">H\u01b0\u1edbng d\u1eabn c\u1ee7a NIST v\u1ec1 c\u00e1c h\u1ec7 s\u1ed1 chuy\u1ec3n \u0111\u1ed5i \u0111i\u1ec7n SI<\/a> \u2014 H\u1ec7 s\u1ed1 chuy\u1ec3n \u0111\u1ed5i ch\u00ednh th\u1ee9c cho \u0111i\u1ec7n, t\u1eeb t\u00ednh, n\u0103ng l\u01b0\u1ee3ng v\u00e0 c\u00e1c \u0111\u1ea1i l\u01b0\u1ee3ng li\u00ean quan.<\/li>\n<li><a href=\"https:\/\/www.osha.gov\/laws-regs\/regulations\/standardnumber\/1926\/1926SubpartV\" target=\"_blank\" rel=\"noopener nofollow\">Y\u00eau c\u1ea7u v\u1ec1 an to\u00e0n \u0111i\u1ec7n c\u1ee7a OSHA<\/a> \u2014 B\u1ed1i c\u1ea3nh an to\u00e0n khi \u00e1p d\u1ee5ng c\u00e1c t\u00ednh to\u00e1n \u0111i\u1ec7n v\u00e0o c\u00f4ng vi\u1ec7c truy\u1ec1n t\u1ea3i v\u00e0 ph\u00e2n ph\u1ed1i \u0111i\u1ec7n.<\/li><\/ul>\n<\/section>\n<!-- lbaji-references:end -->","protected":false},"excerpt":{"rendered":"<p>Converting kVA to amps is one of the most common calculations in transformer, generator, cable and switchgear selection. The arithmetic is simple, but the result is only correct when the phase arrangement and voltage\u2026<\/p>","protected":false},"author":6,"featured_media":2402,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[58],"tags":[84,85],"class_list":["post-2406","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-electrical-engineering-guides","tag-electrical-calculations","tag-kva-calculations"],"blocksy_meta":[],"acf":[],"_links":{"self":[{"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/posts\/2406","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/comments?post=2406"}],"version-history":[{"count":6,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/posts\/2406\/revisions"}],"predecessor-version":[{"id":2691,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/posts\/2406\/revisions\/2691"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/media\/2402"}],"wp:attachment":[{"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/media?parent=2406"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/categories?post=2406"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/tags?post=2406"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}