. Factory and industrial management. at 14,000 volts to eight sub-stations locatedalong the railway lines running to Indianapolis, Marion and ]\ sub-stations are provided with transformers, rotary convertersand storage batteries for furnishing direct current to the trolley addition there is a portable sub-station mounted upon a car whichmay be taken to any point to help out a local sub-station where the loadis temporarily heavy. Some interesting data have been obtained by the Union TractionCompany, showing the cost of power at the bus-bars. In July, 1901,this amounted to $
. Factory and industrial management. at 14,000 volts to eight sub-stations locatedalong the railway lines running to Indianapolis, Marion and ]\ sub-stations are provided with transformers, rotary convertersand storage batteries for furnishing direct current to the trolley addition there is a portable sub-station mounted upon a car whichmay be taken to any point to help out a local sub-station where the loadis temporarily heavy. Some interesting data have been obtained by the Union TractionCompany, showing the cost of power at the bus-bars. In July, 1901,this amounted to $3, for 953,000 KW. hours, or $.00384 The road has been very successful and a number of exten-sions are contemplated. It may be well to draw attention here to one or two general char-acteristics of these plants which we have omitted to mention. It willbe noticed that in all cases a comparatively low number of alternationshas been adopted. The reasons for this are that with a low frequency THE ENGINEERING JXULCTiUX MOTOR DRIVING HELENA^ MONT. the self-induction and capacity effects of the line are correspondinglyreduced; also, a low frequency is more suitable for the operation ofmotors and rotary converters. However, it should be rememberedwhen designing a plant of this sort that the advantages of one fre-quency over another are only relative and that a small change infrequency one way or the other makes little difference; therefore, theengineer v/ill do well to select a standard frequency, such as 25 or 60cycles per second, in order that he may make use of the standardapparatus in the market. It will usually not be found advisable togo above 60 cycles, since that is high enough for most purposes anapermits of the use of alternating-current arc-lamps. On the otherhand, a frequency lower than 25 is unsuitable, since that is about thelowest at which incandescent lamps can be used without flickering. Another characteristic of very high tension ge
Size: 1724px × 1449px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubj, booksubjectengineering
