198001489 - 5530 CURRENT GENERATION

ALTERNATOR

COMPOSITION

The alternator is a rotary machine that transforms mechanical energy into electrical energy.1 - Rotor electromagnetic circuit2 - Fitting rods3 - Rectifier side support4 - Negative heat dissipation plate5 - Positive heat dissipation plate6 - Zener type power press-fit diode7 - Commutator8 - Regulation unit9 - Heat shield cover10 - Rectifier side bearing11 - Rectifier side inner fan12 - Stator electronic circuit13 - Control side support14 - Control side inner fan15 - Control side bearingAs with all electrical machines, it is made up of two basic parts: inductor (rotor) and stator.The rotor for an alternator with internal ventilation is illustrated in the diagram below.

Rotor

The rotor consists of a cylindrical magnetic core, concentric to the drive shaft, with a toroidal coil winding and two opposing magnetic impellers which are magnetized by the winding located in the actual core.The impellers have six talon shaped poles each with reciprocal interpolation producing six alternate North poles and six South poles. There is therefore a single rotor winding which produces the e.m.f. for all the partial magnetic circuits.

Stator

The following diagram shows the stator.1 - Star connection stator2 - Triangle connection statorThe stator consists of a ring shape pack joined by two or more axial seams electrically welded on the outer part. It is normally equipped with thirty six grooves which contain a three-phase winding made from copper wire insulated with vinyl acetate and connected, as necessary, in a star or triangle formation.

Rectifier bridge

The rectifier bridge is illustrated in the diagram.1 - Zener type power diode2 - Dissipation plate3 - Alternator B + terminalBridge specifications

The bridge consists of:

• Zener press-fit diodes.
• Diodes fitted in the dissipator plates electrically welded to the connection terminals.
• Sheared dissipator plates.
• Large dimension dissipators.
• Phase insulation until the connection with the bridge via a rubber cable duct.
• Limitation of excess tension in the case of "+ battery" load disconnection guaranteed by zener diodes.

1 - Normal diode2 - Zener diodeZener diodesThe feature of both diodes, if polarized directly, is to pass the current from the anode to the cathode (V+ I+): then a zener diode behaves like a normal silicon diode.If inversely polarized, the current does not initially pass from the cathode to the anode up to value VZBeyond value VZ the normal diode is destroyed, the zener diode, on the other hand, continues to operate normally because its resistance in these conditions decreases sharply. Zener diodes are therefore voltage stabilizer diodes. Voltages of between 4.7 and 24 Volts are used in cars. It is one of the most important components in the regulation unit.It is often used for protection against polarity inversion or as protection against excess voltage.

SPECIFICATIONS OF INTERNAL VENTILATION ALTERNATORS

The main feature of this type of alternator, with a 115 mm stator diameter, is having dual internal ventilation with the vanes at an angle to guarantee the maximum flow of air and limit noise at the same time.For the same power output alternators with internal ventilation are smaller and lighter than types with external ventilation thereby satisfying current application requirements (there is always less space in engine compartments). In addition to this, in terms of quality, reliability and durability, these alternators meet higher standards than the best competition currently on the market.In depth studies and research have made it possible to introduce measures in production to reduce noise limits produced by various components (fluidynamics, magnetics, mechanics).

Typical voltage curve

The graph below illustrates a typical voltage regulator curve.

TECHNICAL DATA

The types of alternator adopted on this vehicle are summarized in the table.

Engine type	Alternator type
1.4 16V heated	A115IM 14V 45/70A
1.4 16V heated Cold Countries	A115IM 14V 50/105A
1.4 16V air conditioned	A115IM 14V 50/90A
1.4 16V air conditioned Cold Countries	A115IM 14V 55/105A
1.9 JTD 8V	A115IM 14V 50/90A
1.9 JTD 8V Cold Countries	A127IM 14V 70/120A
1.9 JTD 16V	A127IM 14V 70/120A.

BATTERY

SPECIFICATIONS

The main specifications of the batteries used on new models are the active material support plates produced thanks to the calcium lead production technology that has replaced the older antimony lead one.This involves a mechanical stretching process with a continuous lead band resulting in the final production of the grid spread with lead oxide for the positives and metallic lead only for the negatives, rather than the use of casting machines for producing grids through fusion.The use of materials such as lead-calcium-tin alloy guarantees a considerable reduction of the phenomenon of electrolysis in the operation of the accumulator (dissociation of the water into is hydrogen and oxygen components) and the quality of the gases that can escape thereby causing less evaporation of the actual water with a consequent drastic reduction in the maintenance required for this type of battery.

BATTERY TECHNICAL SPECIFICATIONS

The main technical data for the battery is summarized in the table.

Engine type	Battery type
1.4 16V	50Ah - 300 A
1.4 16V Cold Countries	50Ah - 350 A
1.9 JTD 8V	60Ah - 540 A
1.9 JTD 16V	60Ah - 540 A

NEGATIVE BATTERY LEAD TERMINAL

Device for rapid fasteningTo facilitate the removing-refitting of the negative lead from the battery, a new lead with the terminal secured to the negative pole having a rapid release-attachment device controlled by a lever replacing the traditional nut and bolt has been adopted.

Detaching the terminal

Open the lever and detach the terminal.

Take care whilst opening the lever on account of the release device.

Refitting the terminal

Make sure that the release/attachment lever is in the opening position (A).Fit the terminal on the battery pole and press it down fully (end of travel) (B).Tighten the lever (C).

Exert a slight pulling force to check that the terminal is correctly attached.