7.2.4. Check of a current of return of the generator

This test defines, whether there corresponds a current of return of the generator to nominal rate.

Before the beginning of dough execute the following checks and if necessary repair faulty details and units.

Check a condition of the storage battery established on the car.

NOTE The storage battery used at carrying out this check, should be slightly discharged. The loading created by completely charged battery, is not suitable for exact carrying out this check.

Check a tension of a belt of a drive of the generator.

Transfer a key of the lock of ignition to the situation "OFF".

Disconnect a wire from the negative (–) plugs of the storage battery.

Disconnect a regular wire from a conclusion "In" the generator.

Connect the ampermeter (a direct current, with a range 0–100 And) it is consecutive between a conclusion "In" the generator and its regular wire. Be convinced that the wire (–) the ampermeter is connected to the regular wire disconnected from the generator.

NOTE Reliably and densely fix each connection as on conclusions the current of big force will move. Do not use clips (crocodile type) at connection to an electric chain.

Fig. 7.11. Scheme of check of a current of return of the generator

Connect the voltmeter (with a scale 0–20 In) between a conclusion "In" the generator and "weight". Connect (+) a voltmeter wire to a conclusion "In" the generator, and then (–) a voltmeter wire to suitable "weight" (to a body) (fig. 7.11).

Connect a control tachometer according to the instruction of the manufacturer. Connect a wire to (–) the plug of the storage battery.

Leave an engine cowl open.

Be convinced of that the voltmeter shows tension of the storage battery. If the voltmeter shows 0 in, or there was a chain break between a conclusion "In" the generator and (-) the plug of the storage battery, or the fusible insert fused, or bad connection with "weight" takes place.

Start the engine and include headlights of head light.

Include a driving beam of headlights and establish the switch of the electrofan of a heater in the situation "HIGH", then sharply increase frequency of rotation of a cranked shaft of the engine to 2500 ^mines-1 and consider the maximum value of a current of return of the generator (shown by the ampermeter).

NOTE After engine start the charging current quickly falls. Inspect as soon as possible to manage to measure the maximum value of a current of return of the generator.

Indications of the ampermeter should be above limiting admissible value. If indications of the ampermeter are lower than maximum permissible value, and thus the chain of a conclusion of "B" of the generator is serviceable, remove the generator from the car and make its check at the stand.

Maximum permissible value.

the generator 75 A – at least 52,5 And.

the generator 90 A – at least 63,0 And.

NOTE Nominal force of return of the generator is beaten out on the plate attached to the case of the generator. The size of a current of return changes depending on load of the generator and temperature of the case of the generator therefore nominal force of return can be not reached. In similar cases for increase in electric loading (to discharge the storage battery) include for some time a driving beam of headlights or connect system of external illumination of other car. The nominal rate of a current of return of the generator can be not received also as a result of an overheat of the case of the generator or too high temperature of air. In such cases let's to the generator be cooled and execute check repeatedly.

After completion of check of a current of return of the generator gradually lower turns of a cranked shaft of the engine to idling turns, then switch off ignition.

Disconnect a wire from the negative (–) plugs of the storage battery.

Remove the ampermeter, the voltmeter and a control tachometer.

Connect a regular wire to a conclusion "In" the generator.

Connect a wire to the negative (–) the plug of the storage battery.