Dannatt plates are thick sheets made of
electrical conductor
In physics and electrical engineering, a conductor is an object or type of material that allows the flow of charge (electric current) in one or more directions. Materials made of metal are common electrical conductors. The flow of negatively c ...
s, usually
copper
Copper is a chemical element; it has symbol Cu (from Latin ) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orang ...
, positioned around an
AC magnetic circuit to help guide
magnetic flux
In physics, specifically electromagnetism, the magnetic flux through a surface is the surface integral of the normal component of the magnetic field B over that surface. It is usually denoted or . The SI unit of magnetic flux is the we ...
.
[Philip Beckley, Electrical steels for rotating machines, IET, 2002, , page 28]
/ref>
The alternating magnetic field induces eddy currents in the plates. The orientation of these currents opposes the magnetic field. The magnetic field cannot penetrate through the Dannatt plates and is, therefore, directed along them.
References
Magnetism
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