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Società per la illuminazione di Roma col gas ed altri sistemi
| Firmenname | Società per la illuminazione di Roma col gas ed altri sistemi |
| Ortssitz | Rom |
| Art des Unternehmens | Elektrizitätswerk |
| Anmerkungen | Das älteste von "Ganz & Co." (Budapest) nach dem Wechselstrom-Transformatorensystem (Einphasenwechselstrom 2000 V, herunter transformiert auf 105 V) erbaute größere Kraftwerk. Die "Stazione di Cerchi" ist in der Nähe Tiber neben den Ruinen des "Circus maximus". [Wilkens] gibt 1886 als Inbetriebnahmejahr an; die Kerchove-Maschinen wurden lt. Lieferbuch erst Okt./Nov. 1887 bestellt/geliefert (Empfänger: Ganz & Co.), und die "Erste Brünner" nahm erst 1888 den Bau von Schnellläufern auf. Die vier vierpoligen Erregermaschinen waren mit Dampfmaschinen von Westinghouse bzw. Franco Tosi gekuppelt. |
| Quellenangaben | [Hundertjährige Geschichte der Ersten Brünner Masch.-Fabr.-Ges. (1921) 105] [Referenzliste S. 14] [Wilkens: Elektrische Centralen (1906) 33] [Hedges: Continental electric light stations (1892) 4] |
| Zeit |
Ereignis |
| 1886 |
Inbetriebnahme |
| Produkt |
ab |
Bem. |
bis |
Bem. |
Kommentar |
| Elektrizität |
1886 |
Beginn |
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| Bezeichnung |
Bauzeit |
Hersteller |
| Dampfmaschine |
1886/88 |
Erste Brünner Maschinenfabriks-Gesellschaft |
| Dampfmaschine |
1886/88 |
Erste Brünner Maschinenfabriks-Gesellschaft |
| Dampfmaschine |
um 1887 |
Emm. Van den Kerchove, Mécanicien Constructeur |
| Dampfmaschine |
um 1887 |
Emm. Van den Kerchove, Mécanicien Constructeur |
| ZEIT | 1892 |
| THEMA | Beschreibung |
| TEXT | This important enterprise dates from the autumn of 1886, From the very first, at this central station, a new departure in electric lighting was inaugurated, both with regard to the dimensions and disposition of the plant; the arrangement, however, had been exhibited the previous year, by the contractors, at the Electrical Exhibition, Budapest. The station, which is now equal to a supply of 24.000 sixteen-candle-power lamps, has gradually increased. The first order was for two alternating-current machines of 80.000 watts (2000 volts x 40 amperes), each of which was coupled direct to a horizontal high-pressure engine, running at a speed of 250 revolutions per minute. After a short time, these dynamos were found to be taxed to their full capacity, and a second order was given to Messrs. Ganz, for another double plant of 320.000 watts (2000 volts x 160 amperes), each dynamo being driven direct, as in the smaller set, but requiring engines of 500 H.P. The engines are compound, and drive the dynamos by means of a disc fastened to the main shaft; no fly-wheel is necessary on account of the large diameter of the revolving armature. The low speed of 125 revolutions per minute is found to be quite practicable; and, on visiting the station, an engineer is struck with the great advantage of slow direct driving, and mentally compares the quiet working of these colossi with the too often noisy quick-speed engines or flapping belt-driven dynamos he has been used to at home. The exciting continuous-current machines, of which there are four, arc erected in a separate part
of the station. Each dynamo is directly driven by its own steam engine, in the same way as the alternating plant.
The old type of Zipemowsky transformer, with iron wire wound round the copper coils, has been abolished. The iron part is built up of circular, flat, ring-shaped discs of iron, which are firmly clamped together by iron clamps, which form the support of the instrument. The copper coils are wound upon the segments of the rings between the clamps, the primary coil being underneath the secondary. The transformer has an iron circular disc at top and bottom, fixed to the clamps, and this enables the instrument to be easily rolled about without injury, and facilitates handling. On the top are several porcelain discs, on which are placed the terminals and fusible cut-outs, which are somewhat after the Hedges system, and consist of thin fusible strips of metal held between asbestos millboard, so that they can be slipped in and out with the greatest ease. They are all of ten horse-power, with about four amperes in the primary and seventy-five in the secondary, the working pressure in the secondary
circuit is no volts, but the secondary coil has three terminals, as shown, one half way along the length of wire to enable a three-wire system to be employed when arc lamps are wanted, which consume with their resistances 55 volts each. The small alternators are intended to work locx) 60-watt lamps; they have each 20 poles, and run at 250 revolutions per minute. The steam pressure is 120 lbs. The large dynamos have forty poles each on the revolving field magnets; both field magnets are divided into two series in parallel. The efficiency of these machines is said to be go per cent, including the exciting current; they are so constructed that the cover which contains the armature coils can be drawn away by means of a handle over the electro-magnet ring without the necessity of using any hoisting tackle. The construction of the armature is such that any single coil can be removed in a few minutes or exchanged. The iron plates of which these armature sections are made are T-shaped, so that the centre of the coil is filled with iron; in the smaller machines there is not nearly so much iron in the coils. The energy used in exciting the 600 horse-power machine at full load is said to be 3,5 per cent, of the load. The T-shaped iron plates of the armature are pressed together by bronze press plates (s) and a screw (c"); the wire bobbin is then slid on, and held by screws; these segments are fastened to two traverses (t) by the screws (r), which are in turn screwed with an insulating layer (u) to the side-plates of the framework of the machine. The field magnet wheel consists of U-shaped soft iron sheets (k), so arranged as to form a star, to which is added a similar star, with an insulating layer between, placed in such a way that the interstices between the sheets composing the lower star are covered by the sheets on the upper star; in this way many laminx are put one upon the other, until there are sufficient to form the whole electro-magnet wheel. The pile so formed b then pressed togther to form a compact whole by means of two stiff discs, two bosses (n), and the screws (C). The bobbins (m) are slipped on to the core (k), and held down by
means of the bobbin-holder (h) and screws (c'). The subdivision of the iron in the field magnets is necessitated by the teeth of iron in the armature projecting inwards through the coils. The mercury switch-board is about 8 feet high and 17 feet long. It is divided into four sections, one for each dynamo, and each section connected with the
two poles of the dynamo. Two vertical bars descend from these at each of the six parts allotted to the six circuits; six pairs of horizontal bars are connected to the six pairs of feeders, these pairs being one over the other. At each feeder-section a pair of vertical copper bars descend from the horizontal feeder bars corresponding to that
section. Thus we have at each feeder-section two vertical dynamo bars and two vertical feeder bars, the lower ends all being at the same level. Mercury cups can be raised to connect each dynamo bar with a feeder bar, or lowered to disconnect them. The chief object of the switch-board is to switch any number of dynamos in or out of connection with any feeders simultaneously and instantaneously. Referring to the diagram, in the normal condition the crank (A) and handle (B) would be as shown in the side elevation, one crank to each mercury cup (c). If it be required to put on to the dynamo the feeder No, 6, and take off No. r from the dynamo represented by this part of the switch-board, the handles (B) with cranks (a), corresponding to these feeders, are pushed bodily to the left; the web of each crank is thus made to fit in a vertical slot in the disc (e), which disc is connected to the level wheel (g) by a hollow spindle, to which (c) is keyed, this level wheel gearing with the level wheel (H) keyed on to the shaft (I), running the whole length of the switch-board. The crank of Na 6 would be diametrically opposite that at No. i, since one was disconnected and the other connected to a circuit. The lever (l) is then thrown over against the other stop, causing the crank No. 6 to be raised from its lowest to its highest position and that of No. i to be correspondingly lowered. Steam is supplied by fourteen boilers of the water tube type, the steam pipes being so arranged that any portion can be stopped off in case of accident or repairs. An interesting feature of this central station is the fact that it is the property of the Roman Gas Company, who had the foresight to alter, or rather add to, their
original title, "The Company for the Illumination of Rome with Gas", the words "and other systems"; thus following the example of the many American gas companies, who speedily recognized that the electric light would not only be an important addition to their business, but that, by taking it up themselves, rival companies were practically kept out of the field. Siemens' concentric conductors are used throughout the city. The feeders, which are each 220 square millimetres in section (0*35 square inch), all go to the Piazza Venezia, and then branch off into three mains in different directions. The loss in the secondary circuits due to loss in the feeders at present is only 0,6 volt at the maximum, and that due to the mains is the same, the length of the feeders being 1600 metres. The cables are laid in a wooden box, and this is filled with cement. The sub-station high-pressure system has been thoroughly worked out in Rome. Every nest of about 2000 lamps is served by a sub-station containing a bank of twelve transformers, each of seven-and-a-half kilowatt capacity. Means are provided to cut transformers in and out as the load comes on and off. The great waste of the idle transformer is thus prevented ; and by banking them in this way only half the total number of transformers is required, and it enables these appliances to be used in the most efficient maner ? i.e., at full load. |
| QUELLE | [Hedges: Continental electric light stations (1892) 4] |
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