. The Street railway journal . higher rateis advisable, say 120 lbs. per ton, where maximum speedreached is 46J miles per hour and energy 65 watt hoursper ton mile. These values reduced by means of theratio found above gives miles per hour maxi-mum speed reached with 120 lbs. per ton tractive effortand requiring an energy expenditure of 65 watt hoursper ton mile as the constants of a train making per hour schedule speed with ten seconds stops overaverage distances of 2,000 feet between stops. All values of watt hours per ton mile given on curvesheets are net, that is they
. The Street railway journal . higher rateis advisable, say 120 lbs. per ton, where maximum speedreached is 46J miles per hour and energy 65 watt hoursper ton mile. These values reduced by means of theratio found above gives miles per hour maxi-mum speed reached with 120 lbs. per ton tractive effortand requiring an energy expenditure of 65 watt hoursper ton mile as the constants of a train making per hour schedule speed with ten seconds stops overaverage distances of 2,000 feet between stops. All values of watt hours per ton mile given on curvesheets are net, that is they represent only the actual en-ergy consumed in accelerating the train and overcomingtrain friction and hence representing the useful output ofthe motive power. The efficiency of the motors and theirmethod of control entail additional losses which it is notthe intention of the present article to discuss, so that theenergy values given do not represent station capacity ofgenerating apparatus until the efficiency of acceleration,. area inclosed by a is four times b, and maximum speedreached and duration of run in seconds are both double. Thus a ready means is provided for ascertaining theenergy required and maximum speeds reached for anynumber of stops per mile and average speed while trainis in motion. Flaving plotted complete sets of curves forone stop per mile for all conditions of accelerating andcoasting, any similar run may be reduced in the inverseration of v7 n the square root of number of stops per mile a X = ViT where x may be the maximum speed reached, length oftime power is applied, duration of run in seconds, etc.,depending upon the value of a taken. For example, aroad is operating a train with stops every 2,000 feet, andit is desired to maintain a schedule speed of miles perhour including ten seconds stops, wanted the tractive ef-fort, maximum speed reached, and average energy out-put of the motors. Deducting the time lost in stopping,the average speed is i84 m
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectstreetr, bookyear1884
