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Alternator

Every combustion engine car has an alternator. Without it, the battery would quickly run out of power, the engine would stop and the car would not start. What is an alternator and how is it built?

An alternator is a generator of alternating current, often three-phase. It is used to convert mechanical energy into alternating current. In an alternator, current is generated in the stationary stator wiring by the rotating magnetic field of the rotor.

It is commonly used as a power source in motor vehicles. To ensure operation with a battery that requires DC voltage, the alternator has a built-in rectifier on silicon diodes and also contains a built-in voltage regulator.

Alternator housing

  1. Fitting brackets
  2. Housing
  3. Stator
  4. Housing
  5. Rotor magnetic pole
  6. Electric voltage regulator
  7. Slip rings
  8. Rectifier
  9. Vent
  10. Winding
  11. Rotor shaft
  12. Pulley

Typical signs of alternator failure

Battery charge indicator lights steadily

Battery charge indicator flashing intermittently

No battery charge light when the ignition is switched on (with the engine switched off)

Battery discharging rapidly

Battery voltage too low

Noise coming from the engine, increasing in volume as the engine speed increases and disappearing as soon as the V-belt is removed

Most common problems

Cracked housing with no protection against external factors

Dirt and contamination leading to seizure

Worn bearings

Worn brushes

Winding short circuits

Faulty voltage regulator