Mercedes M-Class W163

since 1997 release

Repair and operation of the car

System of a charge - general information and security measures

On all considered models the generator of alternating current is used. At installation of additional electric equipment check that there was enough power of the generator for providing new consumers with the electric power.

The drive of the generator is carried out by a wedge-shaped belt from a bent shaft of the engine.

The generator represents the three-phase synchronous electrical machine with electromagnetic excitement. For transformation of alternating current in constant the diode rectifier is built in the generator. Adjustment of tension is carried out by the built-in microelectronic regulator.

During the operation of the generator the electric current proceeding on an excitement winding creates a magnetic flux around rotor poles. At rotation of a rotor there is a periodic change of its magnetic poles under each tooth of the stator, as a result, the magnetic flux passing through teeth, continuously changes in size and tension. This variable magnetic flux creates the electromotive force (EMF) 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 close to sinusoidal a form of curve EMF.

With a high frequency of rotation of a rotor when its output tension of the generator begins to exceed 13.6-14.6 B, the regulator of tension is locked and current does not pass through a winding of excitement. When tension decreases, the regulator opens again, providing freedom of a transmission of current through an excitement winding. The frequency of rotation of a rotor is higher, the longer the regulator remains locked and, that respectively tension at the generator exit decreases stronger. Process of locking and unlocking of the regulator happens with high frequency therefore output fluctuations remain almost imperceptible and the constants supported at the level of 13.6-14.6 Century can consider tension of the generator.

The system of charging does not demand periodic service, however check state/replacement of a driving belt, the rechargeable battery and its electrical wiring has to be made on a regular basis according to the Schedule THAT (see the Head of the Power supply system and production of the fulfilled gases).

At inclusion of ignition on a combination of devices the control lamp of a charge has to be activated quickly (see the Head Governing bodies and methods of safe operation). If the lamp is not disconnected later short time after implementation of start of the engine or activated in the course of functioning of the last, it is necessary to make check of a condition of components of system of a charge. The refusal of activation of a lamp at inclusion of ignition testifies to its exit out of operation, damage of the corresponding electrical wiring, or violation of serviceability of functioning of the generator (including break of a driving belt).

Security measures at service of the generator

• Never switch-off the battery or the regulator of tension at the working engine;
• Never close the plug of excitement of the generator or the cable fixed on it on weight;
• Do not confuse an order of connection of an electrical wiring of the regulator of tension;
• Remember that turning on of the regulator of tension closed on weight leads to an instant exit it out of operation;
• Never remove the generator at the connected battery;
• Do not confuse polarity of connection of the rechargeable battery;
• Never use when checking onboard electric equipment tension measuring instruments / лампы-пробники, connected to household network (110/220 B);
• When checking a condition of diodes do not give on them voltage more than 12 V and do not apply the mega-ohmmeters which also have high output voltage, - breakdown of diodes will lead to short circuit. Remember that when checking isolation of an electrical wiring by means of a mega-ohmmeter it is necessary to disconnect everything from the generator all electrical wiring;
• At charging of the rechargeable battery without removal from the car track it that both wires were disconnected from it. Do not confuse polarity of connection of the charger;
• Before carrying out on the car of any electrowelding works do not forget to disconnect an electrical wiring from the generator and the rechargeable battery;
• You make any checks of chains and knots of an onboard electrical wiring at the idle engine and the disconnected rechargeable battery;
• Remember that violation of polarity of any connections is accompanied by risk of irreversible failure of the rectifier and regulator of tension of the generator.