Electric Lighting: A Practical Exposition of the Art, for the Use of Engineers, Students, and Others Interested in the Installation Or Operation of Electrical Plants, Том 2D. Van Nostrand Company, 1901 |
З цієї книги
Результати 6-10 із 82
Сторінка 39
... maximum drop D , is- Ri = D IC ( N2 - N ) ( 2 ) In the case illustrated in Fig . 16 the current divides , one - half flowing in each direction , so that it is only necessary to substitute for N in the above formulæ , or N 2 and D = RIC ...
... maximum drop D , is- Ri = D IC ( N2 - N ) ( 2 ) In the case illustrated in Fig . 16 the current divides , one - half flowing in each direction , so that it is only necessary to substitute for N in the above formulæ , or N 2 and D = RIC ...
Сторінка 41
... maximum allowable difference between any two lamps being one volt . Hence / 10 , N = 20 , C = .5 , and D = 1. The ... maximum drop with No. 13 wire is found by ( 1 ) to be D = 10 X .00221 × .5 ( 400 — 20 ) = 4.18 volts . In short , for ...
... maximum allowable difference between any two lamps being one volt . Hence / 10 , N = 20 , C = .5 , and D = 1. The ... maximum drop with No. 13 wire is found by ( 1 ) to be D = 10 X .00221 × .5 ( 400 — 20 ) = 4.18 volts . In short , for ...
Сторінка 42
... maximum difference in voltage in the three systems , the relative weights of copper are , roughly , 4 : 1 : 1 , and the total drop , 1 : 1 : 3.09 volts ; while for the same weights of copper , the maximum differences in pressure are ...
... maximum difference in voltage in the three systems , the relative weights of copper are , roughly , 4 : 1 : 1 , and the total drop , 1 : 1 : 3.09 volts ; while for the same weights of copper , the maximum differences in pressure are ...
Сторінка 43
... maximum value of the drop , its average value being 3 RIL . As an example , let it be assumed that Io L = - R = 60 feet . 12 amperes . .02 ohm per foot . = -- V。- % = 40 . .02 x 12 x u 。- u ' : = ( 120 - x ) . 60 If r be successively ...
... maximum value of the drop , its average value being 3 RIL . As an example , let it be assumed that Io L = - R = 60 feet . 12 amperes . .02 ohm per foot . = -- V。- % = 40 . .02 x 12 x u 。- u ' : = ( 120 - x ) . 60 If r be successively ...
Сторінка 44
... maximum when x = L , and having a value 2 R , IL , which is twice as great as in Case I. This demonstrates that , with a tapering conductor having the same resistance per unit of length at the supply point as a cylin- drical one , there ...
... maximum when x = L , and having a value 2 R , IL , which is twice as great as in Case I. This demonstrates that , with a tapering conductor having the same resistance per unit of length at the supply point as a cylin- drical one , there ...
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Electric Lighting: A Practical Exposition of the Art, for the Use of ... Francis Bacon Crocker Попередній перегляд недоступний - 2016 |
Загальні терміни та фрази
alternating current amperes apparatus arc lamps armature arrangement bulb bus bars cable candle-power capacity carbon cent circular mils conductors conduit connected constant current constant potential copper loss core cross-arm cross-section cut-out device diameter difference direct current distribution drop dynamo effect efficiency electric lighting electrical conductors employed energy equal fact feeders feeding-points filament flow frequency full load fuse globe ground heat hence incandescent lamps inch inclosed arc increase inductance insulation iron joint latter length less machines magnetic maximum mechanical metal meter method motor number of lamps ohms one-half open arc operation ordinary parallel phase pipe placed pole polyphase porcelain practically pressure primary produced reactance regulation represented in Fig resistance rheostat rotary rotary converters secondary circuit shown in Fig shunt side single-phase socket supplied switch temperature terminal three-phase three-wire system tion transformers tube two-phase two-wire two-wire circuit usually voltage volts wattmeter watts winding
Популярні уривки
Сторінка 460 - The lower limit is specified for rubber-covered wires to prevent gradual deterioration of the high insulations by the heat of the wires, but not from fear of igniting the insulation. The question of drop is not taken into consideration in the above tables.
Сторінка 11 - W, we find that the most economical area of conductor is that for which the annual cost of energy wasted is equal to the annual interest on that portion of the capital outlay which can be considered to be proportional to the weight of metal used. Professor George Forbes, in his Cantor Lecture, on " The Distribution of Electricity...
Сторінка 459 - Must be so placed in wet places that an air space will be left between conductors and pipes in crossing, and the former must be run in such a way that they cannot come in contact with the pipe accidentally. Wires should be run over, rather than under, pipes upon which moisture is likely to gather or which, by leaking, might cause trouble on a circuit.