SWITCH 3860569 - Caterpillar

Illustration 1 g00825115
Electrical Schematic of the M1 Series Alternator (35 amp)
Illustration 2 g00825116
Electrical Schematic of the M1 Series Alternator (50 amp)
Illustration 3 g00829818
Electrical Schematic of the HDB Series Alternators The illustrations above show the electrical schematics for the alternators.The alternator has two circuits: the charging circuit and the excitation circuit. The charging circuit functions during normal operation. The excitation circuit functions during normal operation and during start-up. An independent circuit exists for each phase of the stator. The phases are noted as "u", "v", and "w". All alternator schematics are similar except for the 35 amp alternator. The 50 amp alternators, the 65 amp alternator, the 80 amp alternator, and the 95 amp alternator have two extra diodes. The diodes are connected to the neutral point of the stator. The diodes add extra current to the output. The 35 amp alternator lacks the extra diodes. The descriptions that follow show the 35 amp alternator.Charging Circuit
The charging circuit supplies current to the battery and to the electrical systems. The stator windings generate three-phase AC voltage. The positive diodes and the negative diodes change the AC voltage into DC voltage. The DC voltage allows current to flow to the battery terminals.
Illustration 4 g00825118
Charging circuit with phase angle of 120°The flow of current at a 120° phase angle is shown in Illustration 4. The voltage is positive at the output of winding "u". The voltage is zero at winding "v". The voltage is negative at winding "w". The current path is described below:Winding "u", positive diode "u", the "B+" terminal, the "B-" terminal, negative diode "w",