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SUMMARY
The important points of this chapter are summarized in the following paragraphs. You should be
familiar with these points before continuing with your study of test equipment.
A permanent-magnet, moving-coil meter movement (D’ARSONVAL movement) uses the
interaction of magnetic fields to produce movement.
DAMPING is used to smooth out the vibration and to help prevent overshooting of the meter
pointer.
ELECTRODYNAMOMETER movements are usually used in wattmeters. They operate much like
the D’Arsonval meter movement, except field coils are used instead of a permanent magnet.
Electrodynamometer movements measure either ac or dc without the use of a rectifier.
