Charging System: Description and Operation

With Integral Regulator

The Alternator is belt-driven by the engine and generates power to keep the Battery fully charged and to operate electrical systems in the vehicle.

Alternator output is variable and depends on the speed at which the alternator rotor spins, as well as the amount of current passing through the rotor winding. Current flows through the rotor wining is controlled by a Regulator that is built into the Alternator.

The Alternator generates alternating current, which is passed through a series of rectifier diodes and converted to direct current.

Without Integral Regulator

The Battery, Alternator and Voltage Regulator make up the Charging System. With the Ignition Switch in RUN, battery voltage is applied through the solid-state electronic control of the Boltage Regulator. The electronic control applies battery voltage to the Alternator field.

With current in the field and the rotor turning, the Alternator stator produces a DC voltage at B+ terminals (to Battery). If the Alternator output voltage is greater than the Battery terminal voltage, current will flow from the Alternator to the Battery, as well as to the vehicle electrical load.

If the Alternator voltage is less than the battery terminal voltage, current will flow from the Battery to supplement the alternator output in supplying the vehicle electrical load.

Charge Indicator

With the Ignition Switch in START, or RUN, battery voltage is present at the Charge Indicator.

If the Alternator is not generating power, the Regulator inside the Alternator grounds the Charge Indicator through circuit 904 (LG/R). The Charge Indicator illuminates.

When the Alternator is generating power, the Regulator inside the Regulator inside the Alternator applies battery voltage to the Charge Indicator through circuit 904 (LG/R). With battery voltage present at both ends of the Charge Indicator, there is no current flow and the Charge Indicator does not illuminate.