Tram - SpeedyLook encyclopedia

History

First lines

The tram appeared during first half of the 19th century, mû by the animal haulage. The first trams Hippomobile S are built with the the United States (they circulate in 1832 on the line of New York to Harlem and in 1834 with La Nouvelle-Orléans). See also: List of the horse-drawn vehicles. The first rails, in U projecting, create an important embarrassment and cause some accidents. They are supplanted, as of 1850, in New York, by grooved rails, then, in 1852, by rails stripped of projecting (invented by French Alphonse Loubat). The first tram of France is built in the department of the Loire on the road between Montrond the Baths and Montbrison. It makes 15 km and is brought into service in 1837. Later, in 1853 at the time of the World Fair, a line of test is presented on the course of the Queen, in the VIII {{E}} district of Paris. During the exposure of 1867, a service road was carried out by trams with horse-drawn traction and was called “American way-of-iron”.

The tram develops then in many towns of Europe (London, Berlin, Paris, Milan,…). Faster and comfortable that the Bus (circulating on the ways suitable for motor vehicles), the trams have a cost of exploitation high because of animal haulage. This is why the motor traction is quickly developed: with vapor as of 1873, electric starting from 1881 (presentation of the electric traction by Siemens with the Exposure of electricity to Paris and Berlin). The development of the power supply, complexed by the prohibition of the air lines in certain big cities, becomes true extensive only as from 1895 in Paris and in Paris region (Tramway of Versailles).

Technical modernity that the electricity and especially the weak harmful effects generated by this one represent facilitate its fast adoption, once the difficulties related on the production and the transmission electricity were solved. The first electric tram is put in exploitation at Budapest in 1887, while in Switzerland, the first line (Vevey - Montreux - Chillon), on Riviera of Vaud, is open in 1888. In France, it circulates for the first time at Clermont-Ferrand in 1890.

The golden age

The tram makes considerable great strides of the beginning of the 20th century until during the time of the Entre-deux-guerres, with the multiplication of the lines and the increase in the number of users: it is then the principal urban means of transport. Horse-drawn transport almost disappeared from all the European cities and American around the Années 1910, and the Autobus are still in phase of development, gaining of mechanical reliability, but remaining in on this side services offered by the tram. The Automobile - for little time - is still reserved for easy customers.

In North America, Montreal is characterized by the avant-gardism from the Company from the Trams from Montreal, which makes many technological innovations and concerning the exploitation, such as the first tram entirely in steel, the perception of the tariff as of the rise on board, the first trams articulated, and the first panoramic trams for the tourists.

A disappearance partial and temporary of the urban landscape

The sales development of individual vehicles involves in certain cities the fast disappearance of the tram of the urban landscape starting from the Années 1950. Technological advances of the bus making them more reliable, the latter become serious competitors for the tram, because they do not require the installation of an expensive infrastructure, but are satisfied to borrow the roadway whose maintenance costs are difficult to reflect on the various users.

The public authorities invest then especially in the installation of networks of bus, even in road infrastructures and highway intended for a perceived car from now on as the mark of the Progrès. The priority given to road installations is illustrated by the remarks of Georges Pompidou which declares into 1971 that “the city must adapt to the car”.

The networks of trams are not maintained any more nor modernized, which completes to discredit them with the eyes of the public. The old lines, considered as antiquated, then are replaced little by little by lines of bus.

The networks of trams disappear almost completely from North America, of France, French-speaking Switzerland, the British Isles and Spain. On the other hand, they are maintained - and in certain modernized cases - in Germany, in Austria, Belgium in Italy, with the Netherlands, in Scandinavia, German-speaking Switzerland, with the Japan and in all the Europe of the East. In France and French-speaking Switzerland, only the networks of Lille, Saint-Etienne, Marseilles, Geneva and Neuchâtel survive this period, but they are reduced each one with a single line. With the Canada, only the town of Toronto guard its network of trams to the downtown area, following the pressures of citizens.

Rebirth

In France

The oil crisis of 1973, and the increasing problems of urban congestion, involve, in France, a reorientation of the policies of displacement towards public transport of mass. While the Métro is privileged in the French metropolises of Lyon and Marseilles which inaugurates it in 1978, the revival of the Tramway in France intervenes with the contest launched by the Secretary of State Marcel Cavaillé in 1975. It is then about a contest to define the future French standard tram having to equip eight cities: Bordeaux, Grenoble, Nancy, Nice, Rouen, Strasbourg, Toulon and Toulouse. French industry will hardly be mobilized for this beginning again contest of the principles then considered as " vieillots". It is Alsthom (famous Alstom) which is retained and it is then requested from 8 towns of study the tram installation of. The expressed interest is weak, the cities then privileging systems considered as " futuristes" , as the system imagined by Pomagalski for Grenoble which will be finally abandoned in 1979 with the profit of the tram.

Nantes did not form part of the ministerial panel, but it then stands as spontaneously candidate. The project is carried out in its term but not without clashes: it is not only necessary to overcome the skepticism of the population but also the reversals political. Nantes will be nevertheless the first French city to obtain a modern tram in 1985, which will be primarily characterized by a circulation in Exclusive right of way, a spacing with normal way and a collecting of current by pantograph and Caténaire. The Tramway of Grenoble inaugurated in 1988 will bring like major innovation the low floor to 350 mm of the plan of bearing, returning this means of transport accessible to the people with reduced mobility (what was then not the case in Nantes) without the need for resorting to the high quays, this last solution being preferred in North America. This material will found the French standard tram which will be taken again in Rouen in 1994 (network named '' Métrobus '') then on the Parisian suburban lines.

Strasbourg, after having studied the light automatic Vehicle a long time (VALLEY), will be the first French city to couple the installation of the tram with a project of requalification urban and questioning of the place granted to the car downtown. Its tram inaugurated in 1994 with the characteristic design, offering broad picture windows making it possible to admire the city, and run on a grass carpet, will quickly become the emblem of the revival of the tram in France and beyond.

Strasbourg, the first French city to be equipped with nonFrench rolling stock, will put a term at the single design. The experiment of Strasbourg will constitute a turning in the reintroduction of the tram in France, which will not then any more only be regarded separately as collective means of transport but a tool with the building authority of the city.

Many other French cities, like Montpellier, will follow quickly, helped in that by a national policy of support for the investments in the transport infrastructures public, which will end in 2003, and will lead to many inaugurations in the years 2000. One can quote in particular Bordeaux, which after having given up the VALLEY, will introduce, in 2003, a tram which can collect the current on the ground in normal exploitation in order to free itself from the socket-outlet by Caténaire in the historical quarters.

Other cities, such Nancy (cf Tram of Nancy) and Caen but nevertheless concerned to obtain transport infrastructures in exclusive right of way, without to face the costs of initial infrastructures related to the tram, will prefer to obtain guided Trolleybus, so called tyred Tramway.

Elsewhere

Geneva (Swiss) had, at the beginning of the 20th century, a network of tram (urban and local) extremely wide (118 km), but which almost entirely disappeared: between 1969 and 1993, it remained only one tram line in circulation. Since, the rebuilding of an urban network of trams is in hand. For more details, to consult the Swiss articles Trams and public Transport Genevese .

With the the United States, one can quote the example of the town of Portland, in the Oregon, which developed a modern network of trams (as much as possible in exclusive right of way) and does not cease extending it, but also a traditional urban line with a modern tram which shares the roadway system with the other users of the street.

the town of San-Francisco also has a very sophisticated system of tram on two scales: in the downtown area a mainly tourist line forms a museum rolling of the tram while making circulate on a few kilometers of the recovered old material of other networks (Italian for example) and the two famous lines of cable-because , of the Tramway to traction by cable more adapted to the slopes, other tram lines modern behaves like a Métro in downtown area and leaves ground to serve the remainder of the agglomeration.

Evolutions

Complementary to the traditional tram, these evolutions make it possible to cover more space or to cross slopes inaccessible to the traditional tram.

Tram-train

The Tram-train is a system which makes it possible the same oar to circulate on tramcar lanes in downtown area and to connect stations located in periphery, even beyond, while circulating on the preexistent regional railway network.

The material used must be compatible with the traditional railroad (indication, power, resistance). The offer of this means of joint transport contributes to a more effective grid of the whole of the network, in particular in the event of combination with the traditional tram. Very developed in the Germanic countries, and in particular with Karlsruhe (Model of Karlsruhe), this system at summer brought into service in Paris region (Line T4, old line of the Egg cups between Bondy and Aulnay) in 2006. The next startups are with Mulhouse in 2010, with Nantes on the Ligne Nantes-Chateaubriant for 2009 and in the Western Lyonese (this last will not roll yet in urban roadway system) like with Strasbourg; project which was normally to be born in 2008 but which was phased: first phase in 2009, clocking of the line concerned and creation of the line F (future urban course of the tram-train), then the phase with the material specific (Citadis Dualis) to horizon 2011/2012.

In the longer term, there exist other projects with Grenoble, Saint-Etienne, the Réunion etc the majority of the projects are concentrated in Île-de-France, Alsace, and the Rhone-Alps.

Interurban

In North America, the tram-train had taken the form of many interurban (the European equivalent was somewhat… - the secondary lines Belgian); many used interchanged goods trains so with the traditional railway networks (they were exploited under a lawful mode identical to the way-of-iron where the side indication and the functioning orders, rather than the Marche at sight dictate the evolutions of the trains; in the same way, the trams circulating were built there to the same anti-collision standards as the conventional railway cars, being governed by the standards of interchange of coaches of AAR).

Nowadays, only the company Chigago, South-Shore & South-Bend remains: it offers a service of suburbs Chicago _South-Bend; its oars still circulate in the middle of the street at many places.

With the Quebec, one could count on “Quebec Railway, Light, Heat & Power” (Quebec _ Holy-Anne-of-Bowsprit) as well as the Montreal & Southern Counties (Montreal _ Granby), which both were subsidiary Canadian National. On these two lines, trains and trams circulated together.

With the Canada , the service of the O-Train, with Ottawa, in a certain manner a Train-tram is, because rolling stock (oars Talent, of Bombardier) is designed for service on railway line (the oars in fact were intended for the Deutsche Bahn) but is used in urban service. It circulates on a traditional railway line like a suburban train and possibly, the plans envisage rails with the downtown area to make part of its way like a tram. However, modified indication (beacons Indusi and engaged Shifting track S) prevents the intrusion of conventional trains during its circulation because the oars Talent do not satisfy the North-American standards of passive protection against the collisions.

In Europe exist also interurban trams. One can quote for example the line of the Tram of the Belgian side, which traverses north in the south the coast of this country, on 68 km, and which plays a tourist part of foreground, which is added with its function of public transport traditional. This line is only many local connection of tram which existed in Belgium to be maintained.

Tyred tram

Food by the ground

Sometimes one reproaches the tram the unaesthetic aspect of the air lines of contact (LAKE), in particular in the historical centres.

The network of the old Parisian trams strongly suffered from this requirement by using the eccentric process of the studs of food (systems Claret-Vuilleumier , Védovélli , Diatto and Dolter ), then of the food by gutter as at Washington DC, American federal capital and other cities like Nice…. The only advantage was of an esthetic nature, from the absence of wire of food, but the disadvantages were legion, at the same time on the level of construction, but also of maintenance and the exploitation.

This preoccupation with a esthetism explains why the tram of Bordeaux, brought into service in 2003, includes/understands several sections with food by ground (APS): it is done by a third rail, located between those of bearing. It is divided into sections isolated from/to each other and which is automatically powering only when one tram runs or is above.

Battery

In Nice, it was installed in the roof of the tram a battery nickel-metal-hydride able to store energy enough to propel an oar to 30 km/h on several hundred meters. This system, without Catenary S, has the advantage of preserving the places Masséna and Garibaldi, like not obstructing the passage of the tanks of the Carnaval.

Advantages and disadvantages of the tram in terms of town planning

Advantages

The cost of Investissement of the tram is increased, but there remains accessible for a average Ville. A Kilomètre of tram in general represents one the third of the investment for one kilometer of a line of Métro, because there is not to dig; but it is necessary to remake the Voirie and the networks. The operation costs are also important, insofar as it is operating public transport which maintains its installations (ways, electrical installations…) whereas the roadway system is maintained by the community, for the direct benefit of the motorists or the organizations of transport in the buses, which do not pay this service directly.

The air systems, like the Monorail and the light subways (Skytrain and VALLEY - especially its version export), oblige with a town planning dedicated with broad avenues and, as much as possible, of the buildings integrating the stations. At the costs, it is very difficult to obtain them, therefore to compare them.

The Block speed of the tram higher than that of the is drunk, because its Plate-forme is conceived primarily in Exclusive right of way (i.e. excluding the other modes from Circulation) and it takes precedence over the others Véhicule S with the crossroads. This speed makes it gravitational and makes it possible to consider a new organization of displacements in Agglomération. The motor vehicle traffic in downtown area is not encouraged any more, and of the carpark-relay of connection with the tram lines are divided into Périphérie, in order to collect automobile flows moving towards the city. The tariffing of these carparks (coupling with tickets of transport) makes them more advantageous than the cost of one or two hours of Stationnement in downtown area. In certain cases, this system of carpark-relay allows even a time-saver. Nevertheless, the tram has the same disadvantages as the bus and the subway as regards time amplitude, because its circulation stops most of the time between Minuit and the paddle.

Work of installation of the Infrastructure necessary to the tram makes it possible to reconsider fitting-out public and its distribution, by giving a priority to it to a urban landscape pacified by a landscape treatment or a Piéton nisation of strategic spaces in heart of city or district. The construction of a network of tram is thus often coupled with the extension of the sectors Piéton niers with more pushed integration of the needs for the Handicapé S (which do not undergo any more unforeseeable unavailabilities of the additional means of access of the subway, vandalized elevators and escalators). This work also allows a complete restoration of the underground grids less expenses for the owners or owners (pipeline gas or of water old replaced, evacuations of redimensionnées rain water, sewers given on levels…). They also make it possible to install new communication networks (cables, optical fiber) the whole being financed by work of the tram.

The tram, finally, allows reconnecter peripheral districts a long time marginalized compared to the Center-ville.

The place of the tram is where the potential frequentation is too important to be absorptive by a bus (12 m, 18 m or 24 m exceptionally) and too low to justify the high costs of a subway. To note the new trams of Brussels - 43 m length - 258 places offer.

Moreover, the infrastructure of the tram allows, in the long term, the realization of lines of Tram-train, which neither the Autobus and Trolleybus allow, neither the transport guided on tire, nor subways if they are fed by 3rd rail (although, potentially, if a railway system is adopted, of the connections could be made).

An financial advantage is also to note: according to the abundant data by the network of Geneva, the tram is more economic and causes less vibrations than the buses and trolley bus.

Beyond the technical and economic advantages, the tram gets also advantages in terms of Image of the city. One of the imperative reasons of the success which it meets since the years 1980 is related to the idea that it proposes a new image of the cities which choose it. By its visible aspect, its presence in the streets, which clearly differentiates it from the Métro, the tram acts like a powerful vector of renewal of the Représentation of the cities. Moreover, the tram (like besides the bus), makes it possible to the users to remain in contact with the Lumière Nature it, to be able to profit from architectural installations of the city, to be able to visit the districts served as with a tourist system with less expenses and to possibly be able to use to them Cellphone. This is why the manufacturers propose materials whose external aspect adapts to the wishes of the urban decision makers who also seek by this means to act on the image of their city, in a step which can be connected with urban Marketing, but which can also constitute an engine for the Urban renewal.

Disadvantages

Little or at all interest compared to wire data buses (different from the trolley buses) in exclusive right of way: costs higher, equal flow, equal speed, frequency less, much expensive, pollution equal (except sound)…
Cost of high Investment compared to the Bus, which can also be conceived in Exclusive right of way.
slow Speed compared to the subway and definitely lower flow (about: 7000 passengers/hour to the maximum against more: 12000 for the subway).
dangerous hollow Rails for the cyclists when they divide the same roadway as the tram. This disadvantage can be practically eliminated by insertion from an elastic band in the throat (see § according to).
visual Impact consequence of the air infrastructure (in particular Catenary). The food by the ground, as used on part of the network of tram in Bordeaux, can free from this problem, with the help of a significant overcost and a reliability more reduced than that of the " simples" overhead lines.
Although the tram is intrinsically low noise, the advertisement of the creation of such infrastructures can worry the residents, making difficult their acceptance of the project.
In exploitation, a tormented layout of the line with many curves, an installation and a poor maintenance of the way can cause a sound pollution sometimes indeed.
no flexibility of the way, in particular in the event of work even on a small portion of the way, because the tram cannot change rail, it must be replaced by buses

Technology

Sees

The way is generally embedded in the Chaussée, and, in such case, fact call to grooved rails including/understanding a rut intended to accommodate the there circulating roll wheels of the vehicles.

Formerly, one generally called upon a traditional installation of the Rail S on Traverse S out of treated wood and soles, around which one posed the paving stones of the roadway (or that one drowned in the asphalts or the Béton), but with time, of the more sophisticated methods were elaborate.

Certain networks, like those of Amsterdam, in Holland, have recourse to rails of which the throat is filled with an elastic polymer which makes it possible to prevent that the narrow wheels of the bicycles are caught and cause accidents there. The polymer is easily crushed by the wheels of the trams much heavier.

With the generalization of the exclusive rights of way, one attends an abandonment of the grooved rails, which are hardly used than at the places where the way must be drowned in the roadway and on the level of shuntings, crossings or marked curves which require Contre-rail, the grooved rail appearing cheaper then than the installation of a third rail. The tram-train requires 41GP.

Because of exiguity of urban space where the tram generally evolves/moves, the way often includes/understands very marked curves of weak ray which can go down until a minimum from 17,5 meters and even 15 mêtres in the deposits, on a network in normal Voie. The networks in Narrow gauge railway allow radii of curvature even smaller. Rolling stock is designed to be able to negotiate these curves thanks to Bogie S which can turn on a very full angle.

Shuntings

Because of low speed of circulation of the trams and their tiny weight (compared to railway material said heavy ), shuntings can be much less elaborate and can comprise only one mobile blade (in the combs of the deposits in particular). When that they are established on grooved rails, they can moreover not include/understand contre-rail with the right of the heart, the throat acting as contre-rail. In this case the flap is reloaded to guarantee the dimension of protection of the heart.

In the beginning actuated manually by means of a pointed lever, the most used shuntings were quickly automated by means of a Solénoïde ordered by the call of current on a section isolated from the overhead line (actuation of shunting or not if the tram tensile-tests by crossing the section). However, they can always be actuated manually in the event of breakdown using a " saber" , called " pince" with Brussels or key of needle to SNCV. With an aim of decreasing noise pollutions due to the passage of the wheels on the gaps of the hearts of shunting, the surface of the rail is often lowered punctually so that the wheel carries on the way only by its roll (see diagram) .

In France it is the rut of the grooved rail which is raised in order to raise the wheels of the tram. This type of hearts said to " ruts porteuses" is generally selected for the oblique crossings with weak tangent. For the connections, the transfer of weight is done in a traditional way as for the apparatuses in flat-bottom rail.

Propulsion

In the beginning, the trams were horse-drawn. These vehicles were besides déraillables , the coachman carrying out his horses in a direction almost perpendicular to the way, which enabled him to approach the pavement to take on board passengers there. The réenraillement was done then all alone, the coachman carrying out his tram towards the axis of the way.

The steam traction was sometimes employed, either by means of small locomotive S whose connecting rod assembly was generally dissimulated in order not to frighten the horses, or by means of autonomous trams provided with a steam engine.

With an aim of eliminating the harmful effects caused by smoke and the vapor, the traction with the compressed air also had established among.

But all these technologies were erased after the bright demonstration of the electrification by Frank J. Sprague of the network of trams of Richmond (Virginia), had proven, since 1887, that the electric traction was the average ideal of propulsion of the trams.

Initially controlled by together with couplings series/parallel various shuntings, the control of the electric traction was quickly ensured by Semi-conducteur S of power, as soon as their reliability was sufficient to offer a service to high availability.

One will quote some train-trams with propulsion gasoline or diesel. The town of Ottawa (Canada) exploits in particular since 2001 a line of light train called O-Train by means of 3 oars diesel of 72t “Talent BR643 DMU” (Bombardier), as pilot scheme on 8 kilometers (5 stations), before the setting in construction of 2 complete lines. The railway terminology not being an exact science, the traditional trams are also called “light trains” by this network (see this site).

The town of Lausanne (Swiss) exploits a dual-mode tram line, the TSOL (Tram of Lausannois South-west), provided with a diesel auxiliary engine allowing a minimal exploitation in the event of rupture of power supply, as well as the evolutions with the deposit which is deprived of contact system. In fact, in spite of the name of tram, it is rather a light subway, and is today called line M1 in the plan of public transport lausannois.

Some accumulator trams will be also noted.

Braking

The Freinage was ensured a long time by a screw brake handled by the coachman, then the machinist and the wattman (or guard-engine). The weight and speeds increasing, it was quickly decided to call upon the air-operated brake, supplied with a compressor provided with a surge tank. The majority of the trams apply a direct brake, rather than a continuous brake, the trams being seldom exploited out of oars.

Motor coaches PCC made great use of brakes with electric drives, which made it possible to be freed from the compressor.

Certain trams circulating on lines with abrupt profile were equipped with electric brakes, either rheostatic, or with recovery, making it possible to go down from long slopes without overheating the brakes dangerously. The regenerative braking is used more and more, allowing considerable energy saving.

A new promising system is in the course of experimentation: the storage of energy in super condensers, allowing to improve the energy assessment considerably, to even cross portions deprived of air food, a way cheaper than with accumulator batteries, or the APS used by the town of Bordeaux.

Trams PCC

The design of the trams lived a revolution during the Années 1930 when, in 1931, a conference bringing together several presidents of American companies of trams, the Electric Railway Presidents Conference Committee worked out the specifications of the Tramway PCC, the goal being to offer to the travellers comfortable means of transport likely to divert them car.

Power supply

If the networks of trams currently use the electrical energy produced by the large national producers, it was not the case at the end of 19th or the beginning of the 20th century.

At that time, the companies produced they-even them electricity, and resold the possible surplus with local subscribers.

Air food

The first electric tram was supplied by a carriage running on two wire air, and connected to the tram by a flexible cable. This method was named troller (English word trawl , meaning Chalut ), which gave the word trolley . This method was not entirely satisfactory, the carriage tending too often to run off the line.

Then the pole finished by a caster was developed with throat in which came to be embedded the wire of food. Certain networks possibly substituted a wiper for the caster.

The adoption of the pole forced the networks to resort to the return of the current of traction by the rails, which introduced several disadvantages. The stray currents involve the galvanic Corrosion rails and often of metal structures in the vicinity (pipes, structures of viaduct, etc), as well as interferences with a possible indication by track circuits. The danger of electrocution for the occupants of the tram during a derailment, this last seeing its metal parts normally ground connection carried to the potential of the feeder, which exposed the occupants to electrocution if they were simultaneously to pose a foot on the roadway (with the ground) and the other on a metal part of the tram under tension (normally with the ground).

The pole requires the use of Aiguillage S with the junctions.

Other European networks adopted the bow, which makes it possible to do without shuntings on air wire.

The most modern networks, as for them, adopted the pantograph. It will be noted that it is difficult to make cohabit trams with pantographs and pole, the Californian network of PROVIDED (San-Francisco) while having made the painful one discovered at the time of the startup of modern motor coaches at the beginning of the Années 1980. However, the towns of Brussels (line of Tervuren, when it functions like line museum, in addition to its normal exploitation) and Lisbon made a success of co-education pole/pantograph, without notable concern.

If trams and Trolleybus cohabit, it is necessary carefully to isolate the wire from the trolley bus, the return of the current being done by this way.

Supply surface

The air food poses an esthetic problem and for the passage of the heavy loads, it at various times was proposed various supposed systems to make it possible to do without the air wire.

One will note the various systems of trams with studs (Diatto, Dolter and Claret-Vuilleumier), where contacts with the short-nap cloth of the roadway allowed a rail of contact assembled under the case to supply the tram, the electrical circuit being closed, in theory, that at the time of the passage of the tram on the stud. That was carried out either by means of Relais, of mobile contactors, or a Magnetic field emitted by the tram (which had also the advantage of cleaning the roadway of any metal remains, but the disadvantage of causing short-circuits)… These systems tested in Paris were seriously damaged at the time of raw of the Seine in 1910, and the replacement of the power supply was carried out by the installation of an air line, authorized temporarily… which lasted until the suppression of the Parisian network in the Thirties!

This method was forgotten during nearly one century following the invention of the underground gutter. The APS used with Bordeaux at the beginning of the 21e century takes as a starting point one of these systems (relay feeding the rail of contact by section, according to the advance of the tram located immediately at the top).

Underground food

The towns of Paris, Lille, Bordeaux, Nice, Brussels, London, New York and of Washington were provided with trams with gutter.

This system made it possible to bring the food under the level of the roadway, in a gutter located either at the center of the way, or beside the one of the two rails. The current was collected by a “plow” suspended under the tram. In the case of the side gutter, this plow could move from one side to another of the tram.

As it collected the current by two drivers located inside the gutter, that had the advantage of removing the stray currents. But the complexity of its construction justified its use only at the places where it was absolutely essential, mainly by concern of preserving the historical centres of the cities of the concentration of posts and of not very esthetic air lines, one found.

The gutter having to cut the rail to the crossings and shuntings, that generated an additional wear at these places, and an increased noise.

With Brussels there existed in several places of the crossings of two lines with gutters of different technology because exploited by different dealers. Defects in the system of an owner such as for example the magnetizing of the plow because of metals employed and friction against the rails of contact had as a consequence that this type of plow collected metal remains, which fell into the gutter from the competitor to the crossings. That gave place to " wars of caniveau" who obliged the owners to assign an agent to each crossing to place boards there on their gutters at the time of the passage of the trams of the competitor… Suppression of the electric traction by underground gutters with Brussels date of the 12/5/1942.

In addition, the use of the gutter was very constraining. Indeed, the plow could be deployed or withdrawn only with the right of the trap doors. Thus, at the time of a defect of the gutter at a place of the line, it was necessary to deploy an air wire on the whole of the section in gutter if one did not want to stop the service during repair.

The rigidity of operation of this system, the constraints which it generated and the heaviness of its maintenance involved its suppression in the few cities which had obtained.

See too

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