Magneto

Magneto, pronounced mag NEE toh, is an electric generator that provides spark ignition in some internal-combustion engines. Magneto ignitions are used in lawn mowers and in some aircraft and motorcycles. A magneto operates on two basic principles: (1) The movement of a conductor in a magnetic field produces an electric current in the conductor, and (2) A sudden interruption of the flow of the current in the conductor can induce (generate) large voltages.

A magneto consists of a magnet and a conductor made up of one or more coils of wire. The coils may rotate around the magnet, or the magnet may rotate inside the coils. The rotation induces an electric current in the coils. Contacts (connections) touching the coils are then opened, interrupting the flow of current and creating a high voltage in the coils. This voltage produces a spark that ignites fuel in the engine.

Contributor: Glenn A. Burdick, Ph.D., Distinguished Prof. and Dean Emeritus, College of Engineering, Univ. of South Florida.

Magneto

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