The generator works in conjunction with a non-contact transistor voltage regulator 13.3702-01

Voltage regulator 50.3702 can be installed on some cars

The measuring element of the regulator is the zener diode VI, which controls the transistors.

The output transistor changes the current (average value) in the generator field winding circuit and thereby maintains the generator voltage within the specified limits.

Voltage regulator specifications

GAZ-2705 voltage regulator

The regulated voltage should be 13.8-14.5V at the generator speed from 2800 to 12000 min -1, load from 5 to 40 A; temperature from –20 to +80° С.

The voltage drop at the “Sh” and “-” terminals of the regulator at a current of 4 A in the excitation winding circuit and a temperature of 20 ° C is not more than 1.6 V.

The voltage regulator has protection against a possible short circuit in the excitation winding circuit.

Maintenance and repair

Maintenance of the voltage regulator consists in checking its parameters.

Checking can be done directly on the car or at the stand.

To check, you must have a DC voltmeter with a scale of up to 20-30 V and a division value of 0.1-0.2 V.

At an average engine speed (1700-2000 min -1), turn on the low beam and measure the voltage in this mode.

The voltage at the "+" terminal of the voltage regulator should be 13.8-14.5 V at a regulator temperature of 20 ° C.

If, when checking the voltage regulator, the voltmeter reading does not fit within the above limits, the voltage regulator should be replaced.

For the normal operation of the generator and voltage regulator system, the condition of the electrical wiring between the generator, voltage regulator and battery, as well as the reliability of their connection to the case, is very important.

Therefore, before finding malfunctions in the operation of the generator or voltage regulator, it is necessary to carefully check the condition of the specified electrical wiring and the correct connection of the wires.

Defects found during the wiring check (wire breaks, insulation failure, short circuits, soiled tips, etc.) must be eliminated.

The absence of charging current can be caused by the operation of the electronic protection of the voltage regulator in the event of a short circuit in the circuit of the generator excitation winding.

After the short circuit is eliminated, the operation of the regulator is automatically restored.

Voltage Regulator Test

Repair and adjustment of the voltage regulator must be carried out by qualified specialists.

To do this, you need a test bench E242 or make a bench equipped with an electric motor for rotating the generator 161.3701 with a smooth change in frequency up to 3000 min -1 , a battery, a resistor (tube or wire) to create a current load of up to 20 A and a device for testing semiconductor devices.

GAZ-2705 voltage regulator

Scheme of the simplest stand for testing the voltage regulator is shown in fig. 3.

To check, turn on switch 5 and gradually increase the generator speed to 3000 min -1. Then turn on switch 6 and resistor 7 to create a load of 20 A at current indicator 2.

The voltage regulated by the regulator will show the voltmeter 3.

If, when checking on the stand, the voltage regulator gives an over or under voltage, by selecting the resistor R1 (see figure) to achieve an adjustable voltage in the range of 13.8-14.5 V at a regulator temperature of 25 ° C.

If the regulator does not provide normal excitation of the generator, check the voltage drop at the “Sh” and “–” terminals of the voltage regulator at a current in the excitation winding circuit of 4 A.

The voltage drop should not exceed 1.6 V. An excessive voltage drop indicates a regulator failure.

Resistor 5 must have a resistance of 4 ohms before the switch is turned on. After establishing a current of 4 A, according to the current indicator 4, turn on switch 3.

Voltmeter 7 should show a voltage of no more than 1.6 V.

If the regulator does not regulate the voltage of the generator, then first of all it is necessary to check the zener diode, and then the rest of the semiconductor devices.

If the regulator does not provide normal excitation of the generator (current is not supplied to the excitation winding circuit), then first of all it is necessary toImo check the output transistor and, if necessary, the rest. Faulty semiconductor devices must be replaced.