. The Street railway journal . and there will be no rheostaticlosses. As may be seen from Figs. 4 and 5, the motor voltage isentirely independent of the trolley voltage. A standard motor Trolley direct-current motors of the same capacity. In general, alsothe regulator and transformer for a four-motor equipment will,together, weigh approximately the same as a single motor. Acomplete equipment, including all apparatus, will weigh ap-proximately 15 per cent more than a direct-current equipmentof the same capacity. Since the weight of an equipmentusually forms only about one-fourth of the total we
. The Street railway journal . and there will be no rheostaticlosses. As may be seen from Figs. 4 and 5, the motor voltage isentirely independent of the trolley voltage. A standard motor Trolley direct-current motors of the same capacity. In general, alsothe regulator and transformer for a four-motor equipment will,together, weigh approximately the same as a single motor. Acomplete equipment, including all apparatus, will weigh ap-proximately 15 per cent more than a direct-current equipmentof the same capacity. Since the weight of an equipmentusually forms only about one-fourth of the total weight of car,equipment and load, however, an alternating-current carshould in general exceed the weight of a direct-current car byless than 5 per cent. For single cars, run at speeds not over 60 m. p. h., and withtrolley voltage of approximately 1000, it is proposed at presentto use standard direct-current trolleys, except that an insu-lating base will be provided. Protection in handling the trolley Trolley For Small Equipments. FIG. 4.—DIAGRAM OF CAR CONNECTIONS FOR LARGEEQUIPMENTS voltage of 250 has been adopted for single-phase railwaymotors, regardless of the trolley voltage used. In general, the lights in the car will be supplied by a smallauxiliary transformer reducing the trolley voltage to approxi-mately 50 volts. If electric heaters are desired, these may beoperated from the main auto-transformer. The air compressorfor supplying brakes and operating the induction regulator willbe operated by a series alternating-current motor taking cur-rent from the lighting transformer. As a rule, the motors will be connected permanently inparallel, both in two and four-motor equipments. The use ofvoltage control makes series-parallel connections unnecessary FIG. -DIAGRAM OF CAR CONNECTIONS FOR SMALLEQUIPMENTS rope will be afforded by insulators between the rope and thetrolley, and by having a grounded metallic end on the part ofthe rope which is handled. For very high speeds, o
Size: 2812px × 889px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectstreetr, bookyear1884
