Audi A4, S4

since 2000 release

Repair and operation of the car

System of charging - general information and security measures

General information

Bosch generator elements

1 — tension Regulator 2 — the Back casing 3 — the Insulator 4 — the Stator 5 — the Forward bearing 6 — the Condenser 7 — Diode assembly 8 — the Wavy washer of the bearing 9 — the Rotor	10 — Natyazhitel of the bearing 11 — the Back bearing 12 — the Epiploon 13 — the Forward casing 14 — Krylchatka 15 — the Pulley 16 — the Nut 17 — Prostavka 18 — the Spline

The generator of alternating current is installed in the car. At installation of the additional electric equipment check that capacities of the generator was enough for food of this equipment.

The drive of the generator is carried out by a ridge belt from a cranked shaft of the engine.

The generator represents the three-phase synchronous electrical machine with electromagnetic excitement. For transformation of alternating current in constant the rectifier on diodes is built in the generator. Tension is regulated by the built-in microelectronic regulator of tension.

During the operation of the generator the electric current proceeding on an excitement winding creates a magnetic flux round rotor poles. At rotation of a rotor under each tooth of the stator there passes that the southern, North Pole of a rotor and a working magnetic flux passing through stator teeth changes in size and tension. This variable magnetic flux creates the electromotive force in a stator winding. The wedge-shaped form of polar tips of a rotor is picked up in such a way that allows to receive the form of curve electromotive force close to the sinusoidal.

With a high frequency of rotation of a rotor of the generator when tension of the generator becomes more, than 13.6 – 14.6 In, the regulator tension is locked and current does not pass through a winding of excitement. Tension of the generator falls, the regulator opens and again passes current through an excitement winding. The frequency of rotation of a rotor of the generator is higher, the time of the locked condition of the regulator is more, therefore, the more strongly tension at the generator exit decreases. Process of locking and unlocking of the regulator happens with high frequency therefore fluctuations of tension at the exit of the generator are not noticeable, and the constants supported at the level of 13.6 can almost consider it. – 14.6 Century.

The system of charging does not demand periodic service, however a driving belt, the battery and wires with sockets have to be served according to the intervals given in the Head the Current leaving and service.

At inclusion of ignition on a control panel the control lamp signaling about an accumulator discharge has to light up. It has to die away at once after start of the engine. If it does not die away or lights up during the movement, the system of charging is faulty. If the lamp is not lit at ignition inclusion, or the lamp fused, its conducting is torn off or the generator is faulty.

Security measures during the work with the generator

1. Never switch-off the battery or the regulator of tension when the engine and the generator work.
2. Never close the plug of excitement of the generator or the cable fixed on it on weight.
3. Never confuse tension regulator wires.
4. Never turn on tension regulator if it is connected to the weight (instant damage).
5. Never remove the generator if the battery is not switched-off from a contour.
6. At installation of the battery watch that the negative plug was connected to weight.
7. Never use tension indicator which is connected directly in a household network (110 or 220 V). Use only the indicator for 12 Century.
8. Do not check diodes giving of voltage more than 12 V or the megohm meter as it has tension, too high for diodes, and they when checking will be punched (there will be a short circuit). When checking isolation of an electrical wiring the megohm meter it is necessary to disconnect all wires from the generator.
9. If the battery is charged in the established state with the charger, both cables of the battery have to be disconnected. Connect the positive plug of the charger to the positive plug of the battery, and the negative plug of the charger - to the negative plug of the battery.
10. Disconnect all wires from the generator and from the accumulator at electric welding of any details of a body.
11. Check chains and knots of electric equipment and eliminate malfunctions at the idle engine and the disconnected battery.
12. The wrong connection of wires leads to destruction of the rectifier and regulator of tension.