Audi A3

since 1997 of release

Repair and car operation

Audi A3
+ Maintenance instruction
+ Current leaving and service
+ Engine
+ Systems of cooling, heating
+ the Power supply system and production of the fulfilled gases
- Engine electric equipment
   + System of electronic control by ignition and injection
   - Charge and start systems
      Storage battery
      Removal and installation of the storage battery
      Check of the storage battery
      The generator - general information and security measures
      Check of the established generator
      Removal and generator installation
      Check and replacement of brushes of the generator and tension regulator
      Starter - general information
      Check of system of start of the engine
      Removal and starter installation
      Check, removal and installation of the traction relay of a starter
+ Manual box of gear shifting
+ Automatic transmission and models with a full drive
+ Coupling and power shafts
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment
+ Elektroskhema


The generator - general information and security measures


In the car the generator of an alternating current is established. At installation of the additional electric equipment check, that capacities of the generator was enough for a food of this equipment.

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

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

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

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

Before making any works on charging system, it is necessary to familiarize with the following security measures:

1. Never disconnect the battery or a tension regulator 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 wires of a regulator of tension.
4. Never include a tension regulator if it is connected to weight (instant damage).
5. Never remove the generator if the battery is not disconnected from a contour.
6. At installation of the battery watch, that the minus plug was connected to weight.
7. Never use the indicator of tension which is connected directly in a household network (110 or 220 In). Use only the indicator for 12 Century.
8. Do not check diodes tension giving more than 12 In or a megaohmmeter as it has too high tension for diodes and they at check will be punched (there will be a short circuit). At check of isolation of electroconducting by a megaohmmeter it is necessary to disconnect all wires from the generator.
9. If the battery is charged in the established condition by the charger, both cables of the battery should be disconnected. The positive plug of the charger to connect to the positive plug of the battery, and the negative plug of the charger from an otriyets
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 storage battery.
12. The wrong connection of wires leads to destruction of the rectifier and a tension regulator.