Charging System: Description and Operation

The Delco-Remy CS charging system has several generator models available, including the CS-128D. The number denotes the outer diameter, in millimeters, of the stator lamination.

CS generators are equipped with internal regulators.

CS generators use a new type of regulator that incorporates a diode trio. A Delta stator, a rectifier bridge, and a rotor with slip rings and brushes are electrically similar to earlier generators. A conventional pulley and fan are used. There is no test hole.


Unlike three-wire generators, the CS-128D may be used with only two connections: battery positive and an "L" terminal to the charge indicator lamp.

As with other charging systems, the charge indicator lamp lights when the ignition is turned to RUN, and goes out when the engine is running. If the charge indicator is ON with the engine running, a charging system defect is indicated. The indicator light will glow at full brilliance for several kinds of defects, as well as when the system voltage is too high or too low.

The regulator voltage setting varies with temperature and limits the system voltage by controlling rotor field current. Achieve correct average field current for proper system voltage control by varying the on-off time. At high speeds, the on-time may be 10 percent and the off-time 90 percent. At low speeds, with high electrical loads, the on-time may be 90 percent and the off-time 10 percent.