Pic. 9.4. Generator device: 1 - belt pulley; 2 – fan; 3 – basic cover of the generator from the drive side; 4 - stator; 5 - connecting bolt; 6 – rotor with contact rings; 7 - rear support cover; 8 - rectifier unit with diodes; 9 - plastic cover; 10 - voltage regulator with brush holder
Generator - the source of energy in the car (pic. 9.4). When the engine is running, it provides electricity to all units and charges the battery. Depending on the model and equipment, alternators of various capacities can be installed on E-class vehicles.
Power is indicated on the label of the generator. It is driven from the engine by a belt. The generator generates alternating current. Since direct current is required to charge the battery, a semiconductor diode block is installed to convert it to direct current. The latter are very sensitive to high voltage.
Liquid cooled high power generator
Some changes also affected the generator. For the first time, liquid-cooled alternators are installed on the E-Class CDI diesel engines. During operation, the generator releases heat energy to the surrounding coolant, which reduces noise and increases heat output, together with an additional electric heater.
Voltage regulator
The faster the generator armature rotates, the greater the voltage. However, the energy consumers in the car are not adapted to power surges. Therefore, the regulator installed on the generator limits the voltage and at the same time prevents the voltage from being exceeded to charge the battery. The regulator is attached to the generator and regulates the voltage in the on-board network, depending on the ambient temperature and the battery within 13.8–14.5 V. The generator does not require maintenance, since it has no lubrication points. Its brushes are designed for a mileage of 100,000 km. To repair the alternator, contact a Bosch technical center or a workshop.