Yamaha EF4500iSE - Inverter Generator, Theory & Diagnostics Manual

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2-1
Generator Diagnostics
CONVENTIONAL GENERATOR DIAGNOSTICS
Introduction
All conventional Yamaha generators, with the excep-
tion to the EDL6500S, are brushless self-exciting
type generators. There are two methods of brush-
less self-exciting generators.
The first method is by using residual magnetism
within the rotor as a source of excitation. These are
models below 4,000 watts and are referred to as
non-AVR type models.
The second method is through the use of a perma-
nent magnet within the Exciter Field Coil. These are
models that are rated at 4,000 watts or higher and
are usually referred to as AVR or Automatic Voltage
Regulator models, which we will cover in detail
later.
The EDL6500S uses the same basic theory to gen-
erate electricity, with the exception to it’s method of
self-excitation. This is done by supplying DC current
from the AVR circuit board to the rotor, through
brushes that ride on a set of slip rings on the rotor.