ENGG 201 Study Guide - Midterm Guide: Ac Power, Slip Ring, Ohmmeter
3 Oct 2017
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Dc machines: explain the function of a split-ring commutator in a dc generator. The split ring commutator in a dc generator mechanically rectifies the current: explain the function of a split-ring commutator in a dc motor. The split ring is used in dc machines: the slip ring is a perfect rounded ring; Copper is suitable material for the coils, commutator of dc machines. The reasons include: best conductor with less resistance, higher efficiency and lower voltage drop, high melting point, flexible and shapeable. Elec349 midterm review questions: compatible, low cost. It is important that the brushes of a dc generator always placed at the neutral points to produce output induced voltage and reduce sparking. Moving the brushes off the neutral points reduces the output voltage and produces sparking: with the aid of a diagram of a two pole dc generator, briefly explain how armature reaction occurs in dc generator.
