THE JULIEN ACCUMULATOR And Traction System.
(Originally published in
The Electrical World, Nov.20, 1886.)
There is no question to-day more interesting to the electrician than, and hardly any so important to street railway companies and the urban public as, the application of electricity to the propulsion of tram-cars. A critical stage has been reached in the practical development of this latest field of applied electricity, when all that is offered to notice deserves close study. At the present moment, M. Ed. Julien, engineer and electrician of Brussels, is demonstrating in this city the merits of his system of electric traction, and it is arousing unusual attention. We deem it proper, therefore, to give a description, with illustrations, of this system, concerning which some of the foremost street railway men in America as well as in Europe entertain a very high opinion, one that they are preparing to give evidence of in employing the Julien cars on their respective roads.
At the outset, it may be remarked that M. Julien occupies in Belgium a position giving him no small authority in the matter of traction. Besides being himself familiar with tramway operation and conversant with all the needs of the industry, he has for several years devoted himself specially to the problems of electric traction, and more particularly to the use of accumulators for the purpose. As far back as 1881, he organized the Compagnie l'Electrique for introducing the Faure accumulators and the Brush electric light system in Belgium; and being thus one of the first to study practically and seriously the employment of accumulators on street cars, he is better able than many to appreciate the advantages, and to eliminate or minimize the inconveniences attaching to their use. At the time M. Julien began to experiment, the storage battery had fallen into a good deal of discredit that was to a considerable extent justifiable, and that resulted from the instability of the battery. This condition of affairs, observed M. Julien, sprang from the production of the plates on a wrong principle, industrially speaking - that of the oxidation of the lead supporting the active material applied to its surface by whatever process, whether decomposition or addition. The result in either case was that when the plate was formed by the action of the current, the positive was more and more deeply oxidized, so that after a relatively short time, if the battery were put into continuously active service, the supporting substance was wholly transformed into peroxide, a material of little consistency or conductivity. In that state the battery was inert and useless, and it became evident that such conditions afforded no hope of profitable occupancy of any industrial field. And this may be said to be the consensus of opinion on the part of all the physicists who have studied the subject since the discovery of secondary batteries, that is to say, since the beginning of the century. Though of interest, it is not necessary for us to enter here into a description of the early efforts and attempts made to construct a practical storage battery, but on the contrary, we will proceed at once to describe the methods by which M. Julien has achieved success.
M. Julien has followed a principle directly opposite, it is believed, to that heretofore employed, at the same time taking advantage of what had been determined to be proper in the generation of secondary battery currents. After much laborious research, he recognized the fact that by combining different metals, such as lead, mercury, and antimony, in certain definite proportions, an inoxidizable alloy is formed which is found to be eminently adapted for use as supporting plates in storage batteries. Attempts had already been made to give the supporting plate greater consistency, and to that end Faure, and M.Julien, too, also added antimony to the lead from the beginning of their manufacture, but no attempt had been made to render the plate inoxidizable.
By means of the inoxidizable plate M.Julien has succeeded, it is thought, in removing the old objections to the storage battery, the plates remaining rigid and undregoing no deformation. The active material adheres perfectly to the metal plate, due principally to the nature of the alloy employed. The life of the plates as demonstrated by several instances is a long one, and after nearly two years' use they show no deformation.
Some experiments recently made with the Julien cells by Professor Eric Gerard at the University of Liege, France, under the auspices of the International Commission of the late Antwerp Exhibition, show clearly the results obtained by M. Julien's improvements. The following table shows the result of a test made with twenty-four of the cells:
Duration of charge, ............ 7 hours 33 min.
Electromotive force per cell, ...2.35 volts. Average strength of current per
kilogramme, ..................... 1.86 amperes.
Energy absorbed per kilogramme, .. 10,700 kilogrammetres.
Ampere-hours per kilogramme, ..... 14.
The accompanying illustrations, Figs. 3 and 4, show the record of a test made with twenty-nine Julien cells furnished to the Edison Company of Paris. The curves were traced by a registering instrument designed by M. Huber for that purpose. The cells weighed forty kilogrammes each, and were charged at the rate of fifteen ampere-hours per kilogramme and gave at discharge 13 1/2 ampere-hours, showing an efficiency of ninety per cent. The discharge lasted nearly thirty hours, during twenty-two of which no variation of current strength took place, with a fall in potential of only four volts.
View attachment 3
As regards the life of the batteries already referred to above, it is interesting to note that for more than two years Prof. L. Nothomb, of the War School at Brussels, has lighted his house by means of a battery of Julien cells, which are still in a perfect state. Our readers will also remember that after six months' service on the electric car at Antwerp, and also in the exhibition, the cells were pronounced by the jury testing them to be unchanged.
More than any other application, electric traction has exacted the employment of perfect accumulators. The constructors of secondary batteries have been aware of this fact, and hence, in all probability, it happens that this specific use has been so limited. It is impossible to attempt a traction system without batteries that can be depended upon. The work is the most exacting that a battery can be subjected to. The current drawn off varies every minute, and is always at a strength very high in view of the number of elements employed. The incessant shaking of the car is also a cause of rapid deterioration in ordinary electrodes in which the active material is not highly adhesive. It is necessary also that the battery should be extremely light and should require little attention. All these considerations have been borne in mind, and have, M.Julien thinks, been met in his system.
The first experiments undertaken by M.Julien were made in June, 1881 on French tramways with the Faure battery, being the first known application of the kind, on tramways proper. The car then used differed very little from that now seen in New York. The main object of M. Julien, then as now, was, after having obtained the battery he sought, to get a practical car. In tramway exploitation, it is specially essential that the devices used shall be the simplest, as well as easy of manufacture. This double point M. Julien claims to have reached. Another objective point is the utilization of the existing rolling stock, and that he has also studied out successfully.
The car that is now in operation on the Eighth avenue road is, on a cursory glance, indistinguishable from any ordinary street car of the type familiar in New York streets, and capable of carrying from seventy to eighty people. It was built by John Stephenson for the Vienna Exposition of 1873, and thus by a strange and happy turn of events returns to the place of its departure after thirteen years absence. The batteries are placed under the benches; the motor and the running gear are placed beneath the car floor. Under each platform is a regulating apparatus controlled by a hand-lever covered by a circular box. All the mechanism has been devised so as to be easy of operation by men who have had neither electrical nor mechanical training; and this ensures the employment of men accustomed to the road and to street car work generally. The operating parts comprise simply the motor, which is connected by rope gearing to a countershaft, and this in turn is connected with the driving axles by a link-chain of special contrivance. The armature makes from 800 to 900 revolutions per minute, while the wheels make 100 - at normal speed. The car is started up, by turning the lever, without the slightest shock. The movement is, in fact, remarkably smooth and pleasant, and the car can be stopped instantaneously. "The rate of speed is controlled both by the number of elements and by manipulation of the mechanism itself. It is noteworthy that M. Julien depends in no way upon artificial resistances. The rapidity of movement is controlled by the batteries, and full speed, half speed, full stop, and reverse motion are all obtained by the merest turn of the lever. To the regulator are brought the connections of all the sections of the battery, working alternatively in series and in parallel. All the cells discharge uniformly, and can, therefore, be recharged together. Without this provision, the charging of a large number of batteries would be a matter of enormous complication, if not an impossibility, in a regular service. The motor has an ingenious commutator, rendering attendance and inspection very easy, as well as a simple method of changing the rate of armature rotation. Into details we are not at liberty to enter just now. It may, however, be said that, as a whole, as a system, the apparatus is well adapted to the ends it serves. Nothing has been left undone, and all the parts work automatically, rapidly and economically.
The car is well lighted by two incandescent lamps fed by the batteries. The brake is worked by hand, M. Julien considering it unwise to add complication or use up current, by resorting to electricity in this item.
When the car leaves the stable, the recharging of the batteries is effected on a series of benches, on each side of the indoor tracks, as shown in Figs. 5 and 6. The exchange of a charged for an exhausted battery does not occupy more than four or five minutes, and as they are pushed into place, the cells automatically make connection.
Our readers well remember that a highly favorable and flattering report was made relative to the Julien car by the special jury at the Antwerp Exhibition in 1885, when it achieved a notable triumph over several systems and carried off the prize, both on the ground of efficiency and on that of economy. The report of the jury was noticed at great length in The Electrical World od March 20, 1886. The jury of ten comprised representatives of the governments of France, England, Germany and Belgium, as well as a number of experts. The competition lasted from May 3 to Oct. 31, 1885, and was participated in by the Julien car, the Krauss locomotive engine separated from the carriage, the Wilkinson locomotive, also separated, the Rowan engine and carriage combined, and the Beaumont compressed air engine. The report of the jury covered twenty-three points of comparison, embracing the whole range of operation, and was favorable to the electric car in a most remarkable and significant manner. It was especially noted that the accumulators had been in use prior to the trial, and that at the end of the competition they showed no sign of deformation, deterioration or polarization. The weight of the car was 5,654 lbs.; the weight of the accumulators was 2,460 lbs., and the weight of the machinery was 1,232 lbs. The car could carry fourteen passengers inside and twenty outside.
The jury also made special and appropriate note of the fact that the dynamo used for charging the accumulators had an efficiency of only sixty-one per cent., a figure far below the average with modern machines, American dynamos attaining over ninety per cent.
M. Julien calculates that for a daily run of 100 kilometres, or about sixty-five miles, at the rate of six and one-half miles per hour, it would require about seven and one-half horse-power per car when run singly, and only ten horsepower (i.e., five horse-power for each) when two cars are run together at the same speed.
From this the coal consumption will be easily computable. On the most liberal basis of calculation, the cost with accumulators appears to be far below two-thirds that of cable or horse traction.
So far, as regards the advantage to the street car company. There are also great and direct advantages to the public in the use of the electric car as compared with horses. The service is more expeditious; the streets are less crowded and much cleaner; the motion is easier, and the cars are better lighted. Large stables no longer spread over large blocks required for human occupancy, and the whole change is in the direction of improving the condition of the city. Now that the first steps have been taken, the revolution, for it is nothing else, in methods of urban travel, will go on with tremendous rapidity.
It is not alone in Antwerp that M. Julien has given evidence of the value of his system. In Paris he has cars running daily and regularly between the Palais de l'lndustrie and the Place de la Concorde. The awarding committee of the International Exposition of Industrial Arts and Sciences has just given him a diploma of honor, in keeping with that conferred in Belgium. At Hamburg, M. Huber, who holds the right to use the Julien system in Germany, has been running a service since the month of April last, and the two cars have up to date required no repairs. At Brussels, the tramway company is now engaged in equipping to operate one of its lines by the Julien system, after a thoroughly satisfactory trial of two years. The confidence of local capital in the change has been exemplified in the quotations of the stock. Negotiations for control of the system are, it is stated, now pending in London, Paris, and Vienna, as well as for Italy, Spain, and Portugal. The Belgian papers to hand report that Mr. Hargreaves, a Brazilian engineer, who has acquired the rights for South America, is now organizing a staff in Brussels and building his cars to serve as models. The movement is evidently a general one, and deserves attention for that, if for no other reason. In New York a corporation has been formed under the name of the Julien Electric Company, to extend the use of the system all over the United States, and it has now, under the personal supervision of M. Julien, inaugurated the operation of street cars with accumulators, after the manner illustrated by the car described above.
A subject of this nature demands very full treatment, and although we have now devoted considerable space to it, approaching developments will, without doubt, necessitate further and even more exhaustive discussion.
Fig. 1 shows the car now running in New York. Fig. 2 shows a set of accumulators, on the receiving bench in the car stables. Fig. 6 shows a bench without accumulators, and Fig. 5 a bench on which a set has been placed. It will be seen at a glance that the change from horses to electricity, as motive power, can be progressive, and therefore far from costly. Thus on a road with one hundred cars, ten can be "changed over" and equipped for the system, and the price for which the eighty or one hundred horses rendered unnecessary can be sold will more than cover the initial outlay. This is an important consideration with many, and will have its influence in all probability in bringing about the change more quickly.