Three-phase current generator

Two types of generators

Opel installs alternators from Bosch and Delco Remy. They differ from each other only in design, they are mounted on the engine in the same way.

Power

Depending on the model, generators with a capacity of 70, 90 or 100 A are installed in the Vectra. To determine the power of the generators, you need to multiply the indicated maximum current by the rated voltage of 14 V, you get 980, 1260 or 1400 watts.

You have already noticed: the alternator does supply 14V at 12V in the on-board network. Since only with such a small difference in voltage can current flow to the battery in order to charge it.

However, the transmission ratio from the crankshaft belt pulley to the generator belt pulley is chosen so that about «⅔» generator power.

Generator Handling and Precautions

The three-phase current generator, in addition to its rather high power, has a decisive advantage: it supplies current already at idle engine speed. In addition, its graphite brushes withstand mileage well in excess of 80,000 km. As the name implies, it produces alternating current, which we cannot use in a car, because. a battery can, of course, only store direct current. Therefore, three diode rectifiers are built into the generator, which convert the three-phase current into a pulsating direct current. These diodes are sensitive to high voltages and therefore you should consider the following points:

When the generator is running, neither remove nor connect any wire between the battery and the generator. This can lead to an increase in tension (voltage peaks) And «overheat» diode.


The alternator must not operate without a properly connected and serviceable battery. The battery serves as a buffer for the generator to some extent during voltage peaks.

All wiring connections between alternator, battery and body metal or engine block (weight) must be durable. Even a rocking contact can lead to dangerous voltage surges.

When fast charging the battery (can not be used for charging at home) and during electric welding work on the body, both wires must be disconnected from the battery in order not to damage the generator diodes.