Electricians' operating and testing manual; a hand book for men in charge of electrical apparatus, repair men, trouble men, lamp trimmers, and electricians generally (1916)
Horstmann, Henry Charles, Tousley, Victor Hugo, 1875- joint author · Chicago, F.J. Drake & co · leaf 256
impracticable for general use. In Figure 154 is shown the well known Weston in-strument. A permanent magnet M, constructed of aspecially prepared steel having the property of retain-ing its magnetism for an indefinite time, is fitted W7thsoft iron pole pieces. In the space between the polepieces,… … Figure 154 that the resistance to turning due to friction be re-duced to a minimum the coil rests in jewel bearings.Two fiat spiral springs, one above the coil and one be-low it, serve the double purpose of providing a torqueagainst which the coil must act and also carry thecurrent to the movable…
Electrical engineering · Electric testing
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
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