Identifier: electricalnewsen31donm (find matches)
Title: Electrical news and engineering
Year: 1891 (1890s)
Authors:
Subjects: Electrical engineering
Publisher: Don Mills, Ont. (etc.) Southam-Maclean Publications
Contributing Library: Engineering - University of Toronto
Digitizing Sponsor: University of Toronto

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forty-lour days this outfit handled :!.144,89afeet of logs, or an average of 71,474 feet per day. Theaverage was later increased by adding to the transformercapacity, and ran over 77,000 feet per day. .Another in-teresting installation was made in a country where the logshave to be removed from fairly steep hillsides. In this casethe logging apparatus was of a special type, known as theMcFarlane Skyline System, which uses a one and a halfinch steel cable of which one end is anchored to standingtimber on the crest of the hill, and the other fastened to thehoisting drum of the donkey. The cable may be carriedout a distance of four thousand feet where the logs are ofsuch a weight that they will not cause too great a sag.The logs are brought in by a carrier or trolley, and theentire hillside is cleared within its travel. The motors used in this case are 150 h.p., 600 r.p.m.,taking 60 cycle current at 550 volts. They are totally en-closed, and of heavy duty construction. Control apparatus
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Left—Electrically driven log hoist; Right—Translo used in electric logging The electrical news as is niciiiiiteil on the same slctl, and consists of a seven pointcontroller connected to a liank of resistance grids. Thisalso operates the primary circuit, and tlie drive is thus self-contained. The operator has an ammeter in full view, andtl.is to.ijcther with a time element oil circuit breaker, showshim how far he can gi> with the cable, .\nother 7/. h.p.motor is used to ojicrate a compressor which supplies airfor the brakes. Power Transmitted Through WoodsIn this case power is transmitted at ll.ODd volts from thesawmill power plant, which was .iy2 miles from the lojrgingoperations at the time the installation was made. The lineis run through the woods, usin.g the trees as poles and runsat the lo.g.ging end, into a portable sub-station, mounted onflat cars, as shown in the photograph. The sub-station equip-ment consists of 200 kw. oil-cooled transformers, which arcprotected on th

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