Abstract: An automotive alternator includes a thermal switch located in a rear chamber of the alternator enclosed by the housing rear wall and circumferential intermediate wall and the stator and rotor. The thermal switch is mounted on the heat-sinking collector tab of a power transistor in the regulator. In high power, low idling conditions with poor interior ventilation, the thermal switch senses heat produced from the rectifier diodes, rotor, stator and regulator to cut-off generation in over temperature conditions. Rings are furnished on the rectifier diode posts to conduct more heat from the diode body and the stator is potted with a special double dip and bake procedure with a thin viscosity two-part epoxy material.