Charging System - MTD P90 series Shop Manual

P90 Series Vertical Shaft Engines

Charging system

The charging system used on MTD engines consists of
a dual output alternator and a rectifier/regulator.
The charging system has a 5 amp AC output and a
3.75 amp DC output. The alternator consists of two parts;
the rotor and the stator.
• Alternator rotor: The rotor consists of five mag-
nets on the inside of the flywheel that rotate
around a stator that is mounted to the cylinder
block. As the crankshaft and flywheel rotate,
the moving magnets induce a charge in the sta-
tor. See Figure 6.34.
• Alternator stator: The stator consists of copper
field windings around an iron core. The stator is
attached to the engine block beneath the fly-
wheel. See Figure 6.35.
• Rectifier/regulator: The rectifier is a set of four
diodes that convert the AC current into DC cur-
rent. The rectifier also has a regulator circuit
built into it regulates the voltage to a specified
range. See Figure 6.36.
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Magnets
Figure 6.34
Stator
Figure 6.35
Rectifier/regulator
Figure 6.36