Electrical engineer's pocket-book: a hand-book of useful data for electricians and electrical engineers (1901)
Foster, Horatio A. (Horatio Alvah), 1858-1913 · New York, D. Van Nostrand co.; London, E.& F.N. Spon, ltd. · leaf 553
eral feet of water without affecting the operationof the system. Xlie Contact Kuttons are made of cast iron. They are about 4J inchesin diameter, and, when installed on paved streets, project about five-eighthsof an inch above the pavement and offer no obstruction to traffic. This issufficiently… … Fig. 101. Section of Combination Unit.The Combination Units. The bell and pan are entirely inclosed in a cast-iron switch-box. This boxand the contact buttons are made into a complete unit as shown in Fig 20.Each unit consists of three separate castings. The cylindrical cast-ironbox, which incloses…
Electrical engineering
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