. Electric railway review . e line a bank of 800-kilowattoil-insulated water-cooled Scott connected transformers stepup the current to 33,000 volts pressure for transmission tothe Naval Academy Junction substation, miles distant. Here the potential is stepped down by four transformers oflike capacity and fed to the trolley wires extending four waysfrom the junction. The substation which is illustrated is ofample size to receive two more transformers. To provide direct current for the shops and yards at thejunction and for the street trackage in Baltimore and An-napolis there are two sync
. Electric railway review . e line a bank of 800-kilowattoil-insulated water-cooled Scott connected transformers stepup the current to 33,000 volts pressure for transmission tothe Naval Academy Junction substation, miles distant. Here the potential is stepped down by four transformers oflike capacity and fed to the trolley wires extending four waysfrom the junction. The substation which is illustrated is ofample size to receive two more transformers. To provide direct current for the shops and yards at thejunction and for the street trackage in Baltimore and An-napolis there are two synchronous motor-generator sets insubstations at each of these places. These motor-generatorsets take 6,600-volt current from the trolley at 6,600 volts andregenerate it as 600-volt direct current. The units at Baltimore and Annapolis have 300-kilowattsingle-phase motors, while those in the Naval Acadamy Junc-tion substation have two-phase motors. Normally these oper-ate on the secondaries of the step-down transformers for one. Washington Baltimore & Annapolis—Waiting Room in Balti-more Terminal Station. phase and on the incoming trolley from Washington for theother phase. They operate equally well, however, on eithersingle phase. There is a tendency for these machines to bal-ance the voltage between the two phases, which feature isvaluable under some conditions of loading. All the substation apparatus is of General Electric manu-facture. Telephone and Signal Systems. The telephone system comprises a pair of No. 10 gal-vanized-iron wires mounted on 3 by Zy2 inch brown porcelain5,000-volt insulators and having connected to this pair at eachstation and at booths along the lines Kellogg Switchboard &Supply Company telephone sets with 5-bar generators and2,000-ohm ringers. The telephone wires have a single-pintransposition on every fifth pole. Each set of telephone in-struments is protected from high voltages by a General Elec-tric 109-Y one-to-one telephone transformer. On the east
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectstreetr, bookyear1906
