Theory For Non-Avr Type Generators - Yamaha EF4500iSE Theory & Diagnostics Manual

Yamaha Generator Theory & Diagnostics Guide

THEORY FOR NON-AVR TYPE GENERATORS

The diagnostic procedures for all non-AVR models
are the same. It will be necessary, however, to refer
to each models service manual for the exact speci-
fication of voltage and resistance readings.
These models depend on residual magnetism within
the rotor to begin the cycle of electricity.
As the rotor turns, the residual magnetism creates a
small amount of AC voltage within the sub-coil. That
voltage is then sent back and forth between the
condenser and the sub-coil.
That AC voltage is then rectified into DC voltage by
a diode known as the rotor rectifier.
The DC voltage then turns the rotor into a large
magnet.
This process is repeated until the engine is
at full speed and the generator reaches it's
rated output.
The non-AVR type generator relies on a
steady engine speed to maintain a constant
voltage.
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