electrical review and western electric~ review/1909 may 22...of dr. frederick millener, wireless...
TRANSCRIPT
Michael Sol Collection
May 22, 1909 ELECTRICAL REVIEW AND WESTERN ELECTRIC~ 933
not desirable to open a circuit immediately, for example, an overload of veryshort duration on an important feedermight not be harmful, and yet be decidedly dangerous if of a few seconds' dura-
FIG. 200.-HIGH-TENSION OIL CIRCUITBREAKER, SHOWING OIL TANK
AND CONTACTS.
tion. The bellows type of relay, a diagram of which is shown in Fig. 201, is designed to control an oil switch in thismanner. The bellows is at the top andwhen the iron core of the solenoid is actu-
FIG. 201.-TI~fE-LIMITOVERLOAD RELAY.
ated by the coil it can move but slowlybecause of the slow escape of the air fromthe bellows. As the solenoid is drawn inthe bellows moves upward and the operating-circuit terminals below it are closed.
The inverse time-limit relay is so ar-
ranged that the retarding action varie~
inversely with the current flowing, so thatthe greater the current the quicker therelay will respond. Relays are also madethat open the switches when the line current, or one phase of it, reverses. Theuse of various kinds of relays permits theuse of simple oil switches that may beopened at will or automatically undervarious abnormal conditions.
Switchboard design.-The design of aswitchboard is a problem to be workedout for each installation. 1.'here are manyitems to consider and a wide range of selection as to instruments and methods ofconnection. Among the desirable featuresto be observed in laying out a switchboardare: Accessibility of all parts, fireproofconstruction, keeping live parts from thefront of the board, simple and "foolproof"arrangement of circuits, provision ofabundant protective devices, as well as indicating and recording instruments forproper operation of the units and for recording their output. :Many of thesepoints have been touched on already.
The multitudinous pOBsible arrangements of circuits, switches and instruments in a switchboard is a subject verylarge in itself and beyond the scope ofthis series of articles, which have attenlpted to give only an outline of thegeneral principles involved in the gent:'ration and utilization of the alternating-currents most commonly employed at thepresent time.
[THE END.]
---.•.---Lights Controlled by Wireless.
The recent Omaha Electrical Show waslighted through wireless telegraphy during one evening, the first time that alarge lighting current has been controlledwithout wires. The system is a discoveryof Dr. Frederick Millener, wireless expertof the Union Pacific.
Four thousand incandescent electriclamps were controlled from a wireless telegraph station at Fort Omaha, five milesfrom the building. A dozen times duringthe evening Dr. Frederick :Millener turnedon and turned off every light in the bigbuilding from his station.
The current, as sent out from the Government wireless station at the fort, waspicked up by the antennm on the roof ofthe Electrical Building. From this itpassed to a coherer, which in turn set thecurrent to energizing a four-ohm trackrelay. This relay closed a circuit solenoidswitch, thereby turning on a seventy-fivehorsepower current and the lights flashedon.
Electrification of Railways.The question of the further electrifica
tion of the New Haven Railroad is receiving the earnest attention of the officials.The electrification of the New Haven fromthe Harlem River to Stamford, Conn.,cost $5,000,000 in round figures, and theoperation has been sufficiently successfulto warrant an extension of the service.
It is now planned to increase the installation for passenger traffic from Stamford to New Haven, a distance of thirtynine miles; also to increase the installation to provide for the electric operationof freight trains between New Haven andthe Harlem River, as well as the electricalequipment of the branch running betweenNew Rochelle and the Harlem River forboth freight and passengers.
The total cost of such additional installation is placed by electrical engineers atabout $12,000,000.
The question of the saving in operatingcosts of electricity, compared with steam,is still a debatable one, though the bestestimates would indicate a saving in favorof electricity equal to between four percent and five per cent on the total cost ofinstallation of $17,000,000, this latter figure including the cost of the present installation between Harlem River andStamford.
This saving alone might not justifysuch a large expenditure were there ~o
other factors to be considered, such as increased business, ability to handle a largerbusiness to better advantage and the general convenience of not only the travelingpublic, but the general public as well, byreason of the absence of dirt, smoke andexcessive noise.
---.•.--A Broad Charter.
Last week a charter to operate a neighborhood line was granted the EffinghamTelegraph and Telephone Company ofEffingham, Ga. Occasion was taken inthe charter application to reserve theprivilege of establishing a continentalsystem of telephones. The incorporatorsask that they not only be authorized toinstall a local system, but be given theright to extend it into all the towns,cities and counties of Georgia and intoall the cities, towns and counties of allthe other states or territories of theV"nited States, including the Districtof Columbia. The capitalization is $5,000.
It is understood that the company docsnot intend doing a cable business, or"island possessions" would have been included in its field of possible operation.