Article October 16, 1902 Issue

Speed Tests of Steam and Electric Trains

A series of tests have recently been carried out on the experimental track of the General Electric Company at Schenectady. These tests were made with a view to determining the relative efficiency of steam and electric traction in suburban passenger service. The primary object of the test was to make a comparison of the rate of acceleration of the same train when hauled by an engine and by a pair of electric motor cars, such as would be used were the suburban lines to be equipped with third-rail electric traction. For the purpose of the test, a train of six cars was made up, which included five standard passenger coaches preceded by a dynamometer car.

The engine selected was one of the big tank engines especially designed for suburban service, provided for this purpose with large heating surface and cylinder capacity, and small-diameter six-coupled drivers. For the electric test two General Electric motor cars, one weighing 73,000 pounds and the other 70,000 pounds, were used. These cars are 54 feet over all in length, and are equipped with four motors, the two cars together giving about the same weight on drivers as the steam locomotive. The test was therefore, perfectly fair, the acceleration being directly comparable for trains of equal weight. The drawbar pull, speed, and the time were recorded by the same dynamometer car in all cases, the engine simply being unhitched and the two motor cars coupled up for the alternate trials. In carrying out the tests, the train of six cars with its engine or its electric motors, as the case might be, was started from rest and run over one mile of track, the acceleration being made as rapidly as possible with the power available. These runs were repeated, dropping off one car at a time, and a careful record was kept of the speed attained in ten seconds, twenty seconds, thirty seconds, etc. The total weight of the train behind the engine or electric cars varied from one hundred and fifty-seven tons down to twenty-three tons.

The comparison of results proves that the electric motors can better utilize the weight upon their drivers during acceleration than a steam locomotive, the motor covering the same distance in the same time with less energy expended, and at less maximum speed than a steam locomotive, owing to its being able to maintain its maximum accelerating rate for a longer period.

Send a comment to the editors

NEXT IN THIS ISSUE

Article

The Cedars of Lebanon