Generator Description

The Delco-Remy CS charging system (CS-121 DIF) is equipped with internal regulator. A Delta stator, a rectifier bridge, rotor with slip rings and brushes are electrically similar to earlier generators. A conventional pulley and fan are used. There is no test hole.

The CS 121 DIF has only two connections: battery positive and "L" terminal to the charge indicator lamp. The charge indicator lamp lights when the ignition switch 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. This 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. At high speeds, the on-time may be 10 percent and the off-time 90 percent. At low speeds, with high electrical loads, on-time may be 90 percent and the off-time 10 percent.