To find the power of an electric current in terms of horse-power, find the number of watts by multiplying the volts by the amperes and divide the watts by 746 and the result will give you the horse-power of the current.
APPENDIX P
NUMBER, DIAMETER, CAPACITY, WEIGHT, AND RESISTANCE OF PURE COPPER WIRE
| Gage, B. & S. No. | Diameter in 1000ths. | Sectional Area in Circular Mils. | Capacity in Amperes | OHMS | FEET | POUNDS | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Per 1,000 feet | Per Mile | Per Pound | Per Pound | Per Ohm | Per 1,000 feet | Per Ohm | ||||
| 0000 | .460 | 211600. | 312. | .0490 | .2590 | .00007 | 1.5612 | 20497.7 | 640.59 | 12987. |
| 000 | .40964 | 167805. | 262. | .0618 | .3266 | .00012 | 1.9687 | 16255.27 | 507.85 | 8333. |
| 00 | .3648 | 133079. | 220. | .0780 | .4118 | .00019 | 2.4824 | 12891.37 | 402.83 | 5263. |
| 0 | .32486 | 105534. | 185. | .0983 | .5190 | .00031 | 3.1303 | 10223.08 | 319.45 | 3225. |
| 1 | .2893 | 83694. | 156. | .1240 | .6549 | .00049 | 3.9471 | 8107.49 | 253.34 | 2041. |
| 2 | .25763 | 66373. | 131. | .1564 | .8258 | .00078 | 4.9772 | 6429.58 | 200.91 | 1228. |
| 3 | .22942 | 52634. | 110. | .1972 | 1.0414 | .00125 | 6.2765 | 5098.61 | 159.32 | 800. |
| 4 | .20431 | 41473. | 92.3 | .2486 | 1.313 | .00198 | 7.9141 | 4043.6 | 126.35 | 505. |
| 5 | .18194 | 33102. | 77.6 | .3136 | 1.655 | .00314 | 9.9798 | 3206.61 | 100.20 | 318. |
| 6 | .16202 | 26251. | 65.2 | .3954 | 2.088 | .00499 | 12.5847 | 2542.89 | 79.462 | 200. |
| 7 | .14428 | 20817. | 54.8 | .4987 | 2.633 | .00792 | 15.8696 | 2015.51 | 63.013 | 126. |
| 8 | .12849 | 16510. | 46.1 | .6529 | 3.3 | .0125 | 20.0097 | 1599.3 | 49.976 | 80. |
| 9 | .11443 | 13094. | 38.7 | .7892 | 4.1 | .0197 | 25.229 | 1268.44 | 39.636 | 50. |
| 10 | .10189 | 10382. | 32.5 | .8441 | 4.4 | .0270 | 31.8212 | 1055.66 | 31.426 | 37. |
| 11 | .09074 | 8234. | 27.3 | 1.254 | 6.4 | .0501 | 40.1202 | 797.649 | 24.924 | 20. |
| 12 | .08080 | 6530. | 23. | 1.580 | 8.3 | .079 | 50.5906 | 632.555 | 19.766 | 12.65 |
| 13 | .07196 | 5178. | 19.3 | 1.995 | 10.4 | .127 | 63.7948 | 501.63 | 15.674 | 7.87 |
| 14 | .06408 | 4107. | 16.2 | 2.504 | 13.2 | .200 | 80.4415 | 397.822 | 12.435 | 5.00 |
| 15 | .05706 | 3257. | 13.6 | 3.172 | 16.7 | .320 | 101.4365 | 315.482 | 9.859 | 3.12 |
| 16 | .05082 | 2583. | 11.5 | 4.001 | 23. | .512 | 127.12 | 250.184 | 7.819 | 1.95 |
| 17 | .04525 | 2048. | 9.6 | 5.04 | 26. | .811 | 161.29 | 198.409 | 6.199 | 1.23 |
| 18 | .04030 | 1624. | 8.1 | 6.36 | 33. | 1.29 | 203.374 | 157.35 | 4.916 | .775 |
| 19 | .03589 | 1288. | 8.25 | 43. | 2.11 | 256.468 | 124.777 | 3.899 | .473 | |
| 20 | .03196 | 1021. | 10.12 | 53. | 3.27 | 323.399 | 98.9533 | 3.094 | .305 | |
| 21 | .02846 | 810. | 12.76 | 68. | 5.20 | 407.815 | 78.473 | 2.452 | .192 | |
| 22 | .02534 | 642. | 16.25 | 85. | 8.35 | 514.193 | 62.236 | 1.945 | .119 | |
| 23 | .02257 | 509. | 20.30 | 108. | 13.3 | 648.452 | 49.3504 | 1.542 | .075 | |
| 24 | .0201 | 404. | 25.60 | 135. | 20.9 | 817.688 | 39.1365 | 1.223 | .047 | |
| 25 | .0179 | 320. | 32.2 | 170. | 32.2 | 1031.038 | 31.0381 | .9699 | .030 | |
| 26 | .01594 | 254. | 40.7 | 214. | 52.9 | 1300.180 | 24.6131 | .7692 | .0187 | |
| 27 | .01419 | 201. | 51.3 | 270. | 84.2 | 1639.49 | 19.5191 | .6099 | .0118 | |
| 28 | .01264 | 159.8 | 64.8 | 343. | 134. | 2067.364 | 15.4793 | .4807 | .0074 | |
| 29 | .01125 | 126.7 | 81.6 | 432. | 213. | 2606.959 | 12.2854 | .3835 | .0047 | |
| 30 | .01002 | 100.5 | 103. | 538. | 338. | 3287.084 | 9.7355 | .3002 | .0029 | |
| 31 | .00892 | 79.7 | 130. | 685. | 539. | 4414.49 | 7.7214 | .2413 | .0018 | |
| 32 | .00795 | 63. | 164. | 865. | 856. | 5226.915 | 6.1224 | .1913 | .0011 | |
| 33 | .00708 | 50.1 | 206. | 1033. | 1357. | 6590.41 | 4.8557 | .1517 | .00076 | |
| 34 | .00630 | 39.74 | 260. | 1389. | 2166. | 8312.8 | 3.8496 | .1204 | .00046 | |
| 35 | .00561 | 31.5 | 328. | 1820. | 3521. | 10481.77 | 3.0530 | .0956 | .00028 | |
| 36 | .005 | 25. | 414. | 2200. | 5469. | 13214.16 | 2.4217 | .0757 | .00018 | |
| 37 | .00445 | 19.8 | 523. | 2765. | 8742. | 16659.97 | 1.9208 | .0600 | .00011 | |
| 38 | .00396 | 15.72 | 660. | 3486. | 13722. | 21013.25 | 1.5229 | .0475 | .00007 | |
| 39 | .00353 | 12.47 | 832. | 4395. | 21896. | 26496.237 | 1.2077 | .0375 | .00004 | |
| 40 | .00314 | 9.88 | 1049. | 5542. | 34823. | 33420.63 | 0.9798 | .0299 | .00002 | |
APPENDIX Q
NUMBER OF TURNS OF WIRE THAT CAN BE WOUND IN A GIVEN SPACE
| No. B. & S. or American Gage | COTTON | SILK | ||||||
|---|---|---|---|---|---|---|---|---|
| SINGLE | DOUBLE | SINGLE | DOUBLE | |||||
| Per Square Inch. | Per Square Qu. Inch | Per Square Inch. | Per Square Qu. Inch | Per Square Inch. | Per Square Qu. Inch | Per Square Inch. | Per Square Qu. Inch | |
| 20 | 676 | 42 | 576 | 36 | 841 | 52 | 676 | 42 |
| 21 | 842 | 53 | 625 | 39 | 961 | 60 | 842 | 53 |
| 22 | 1.024 | 64 | 729 | 45 | 1.225 | 76 | 1.024 | 64 |
| 23 | 1.024 | 81 | 900 | 56 | 1.521 | 95 | 1.296 | 81 |
| 24 | 1.600 | 100 | 1.089 | 68 | 1.936 | 121 | 1.600 | 100 |
| 25 | 1.849 | 115 | 1.296 | 81 | 2.304 | 144 | 1.849 | 115 |
| 26 | 2.209 | 138 | 1.440 | 90 | 2.916 | 182 | 2.209 | 138 |
| 27 | 2.500 | 156 | 1.600 | 100 | 3.249 | 206 | 2.500 | 156 |
| 28 | 3.025 | 189 | 1.849 | 115 | 4.096 | 254 | 3.025 | 189 |
| 29 | 3.481 | 218 | 2.025 | 126 | 4.761 | 297 | 3.481 | 218 |
| 30 | 4.356 | 272 | 2.500 | 156 | 6.400 | 400 | 4.356 | 272 |
| 31 | 5.001 | 315 | 2.704 | 169 | 7.769 | 485 | 5.041 | 315 |
| 32 | 5.929 | 370 | 3.025 | 189 | 9.025 | 564 | 5.929 | 370 |
| 33 | 7.089 | 443 | 3.481 | 218 | 11.025 | 689 | 7.089 | 443 |
| 34 | 7.769 | 485 | 3.600 | 225 | 12.321 | 770 | 7.769 | 485 |
| 35 | 8.100 | 506 | 3.844 | 240 | 13.689 | 855 | 8.100 | 506 |
| 36 | 10.000 | 625 | 4.356 | 272 | 17.689 | 1.105 | 10.000 | 625 |
| 37 | 11.025 | 689 | 4.761 | 297 | 20.164 | 1.240 | 11.025 | 689 |
| 38 | 12.321 | 770 | 5.041 | 315 | 23.716 | 1.482 | 12.321 | 770 |
| 39 | 13.689 | 855 | 5.476 | 342 | 27.556 | 1.722 | 13.689 | 855 |
| 40 | 15.625 | 976 | 5.929 | 370 | 32.761 | 2.047 | 15.625 | 976 |
(W. J. Clarke.)