Electricians' operating and testing manual; (1910)
Horstmann, Henry C. [from old catalog], Tousley, Victor Hugo, 1875- [from old catalog] joint author · Chicago, F. H. Drake & co · leaf 252
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 wTithsoft iron pole piece. 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 flat 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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