Three-level voltage regulator (functions, installation, advantages)

A modern car is densely saturated with numerous instruments and devices, the performance of which is determined by receiving power from the on-board DC network. When the engine is running, the current source is an electric generator, the rotor of which rotates due to the presence of a mechanical connection with the shaft. The engine speed varies widely, causing the generator output voltage to fluctuate. To reduce voltage variations to the required value, a stabilizer is installed at the output of the rectifier, which is made in the form of a relay regulator.

Car alternator output voltage problem

The list of functions of the generator necessarily includes recharging the on-board battery, which is carried out with a certain current to ensure a long service life. The simplest way to set its value is to slightly exceed the voltage taken from the output of the relay-regulator over the current value of the battery voltage. In this case, a serious problem immediately arises, which is due to the fact that, depending on the ambient temperature, the value of this excess should be different.

An obvious and fairly easily implemented solution to obtain a given output voltage using temperature correction of the regulator response threshold by installing an appropriate sensor is of low efficiency. The reason for this is that the temperature in the engine compartment, due to its proximity to a heated engine, differs from the air temperature, and it is not possible to determine the degree of this difference by simple means.

Another problem in determining the set value of the charging current is due to the fact that even at a constant ambient temperature, the load on the on-board network varies within wide limits. This leads to a “failure” in the battery charge level and difficulty starting a cooled engine after parking.

A good way to solve these problems is to switch to a relay-regulator, which makes the necessary adjustments by discretely changing the voltage that the generator creates. The specified value of the response threshold of this device is set by the driver independently using a three-position toggle switch. Some regulators connect automatically and contain an internal sensor that monitors the instantaneous value of the on-board network voltage. In both cases, the selection of the cutoff threshold is carried out taking into account external factors, primarily the current temperature and operating conditions of the vehicle.

Checking the work

Switch position “min” - for operation at high ambient temperatures (above 20ºС), as well as during operation in particularly difficult conditions (traffic in traffic jams, long climbs in the mountains, etc.);
The middle position of the switch is for operation at ambient temperatures from 0ºС to 20ºС;
The “max” switch position is for operation at low ambient temperatures (below 0ºC), as well as for recharging a discharged battery.

Average load (PTF, dimensions, music and heater fan at first speed)

Maximum load, maximum number of consumers activated

Will you be installing a three-level voltage regulator on your car? Take part in the survey and leave your feedback in the comments.

Let us remind you that another reason for low voltage on the on-board network may be a bad ground.

Share on social networks:

Advantages of using a three-level relay and features of its installation

In practice, three-level regulators designed for the 9th and older VAZ models have become widespread. This is due to the fact that replacing the standard relay with a three-level one provides the following advantages:

stabilization of alarm operation in severe frosts;
increasing the brightness of headlights and interior lighting lamps;
a sharp increase in the efficiency of the heater;
increasing the speed of power windows.

Kits for VAZ “ten” and 14th models are quite common; there are also devices for “Volga” and “Gazelle”. Their use on these vehicles gives a similar effect.

A three-level relay-regulator is purchased in the form of a ready-to-install kit, which includes detailed illustrated instructions. The main elements of the kit are a contact group, a relay itself with a slide-type switch for selecting the stabilization voltage, and connecting wires.

Before starting replacement work, it is advisable to charge the battery and then disconnect its negative terminal.

The contact group of the new device is mounted directly on the seats of the previously dismantled old one; installation does not require the use of adapters and other auxiliary elements. The connecting wire is pulled through the generator cover (you may need to cut a hole in it to the required size), and the relay itself is attached to a free mounting stud with the terminals facing down. When installing, additionally check for reliable ground contact. After installing and assembling the generator, we check it.

Carrying out diagnostics of RN with your own hands

Now we’ll tell you how to check a three-level voltage regulator with your own hands. The procedure for checking the regulator can be carried out both at a service station and in a garage, but we will consider the second option. Testing a voltage regulator of 40 amps or less should be done using a tester - a voltmeter or a multimeter. It should also be taken into account that fault detection in the operation of the launch vehicle should be carried out exclusively with a fully charged battery.

So, how to check the generator voltage regulator using a tester:

First of all, you need to open the hood and turn the key in the lock, turning on the ignition.
Next, the power unit is started. The engine should idle for some time; to obtain more accurate diagnostic data, it is recommended to turn on the optics. The engine speed when running should be around 2.5-3 thousand. For the internal combustion engine to switch to this operating mode, you usually need to wait about 10 minutes.
Then the tester probes are connected to the battery terminals. When you connect the tester, diagnostic indicators should appear on its display, ideally they should be approximately 14.1-14.3 volts.

If the check shows other values, be they higher or lower, then you need to start repairing the generator unit. But as practice shows, the problem usually lies precisely in the launch vehicle, so most likely it will have to be replaced. Before you begin diagnostics, make sure that the belt is properly tensioned . During diagnostics, contacts must not be closed, as this may cause deformation and failure of the rectifier unit.

Types of regulator relays

Before you independently repair the voltage regulation device, you must take into account that there are several types of regulators:

external – increase the maintainability of the generator
built-in – in the rectifier plate or brush assembly
regulating by minus - an additional wire appears
positive regulating – economical connection scheme
for alternating current generators - there is no function for limiting the voltage on the excitation winding, since it is built into the generator itself
for DC generators – an additional option for cutting off the battery when the internal combustion engine is not working
two-level - obsolete, rarely used, adjustment by springs and a small lever
three-level – supplemented with a special comparison device board and a matching indicator
multi-level - the circuit has 3 - 5 additional resistors and a tracking system
transistor - not used in modern cars
relay – improved feedback
relay-transistor - universal circuit
microprocessor - small dimensions, smooth adjustment of the lower/upper threshold of operation
integral - built into brush holders, therefore they are replaced after the brushes wear out

Attention: Without modification of the circuit, the “plus” and “minus” voltage regulators are not interchangeable devices.

DC generator relay

Thus, the connection diagram for the voltage regulator when operating a DC generator is more complicated. Since in the parking mode of the car, when the internal combustion engine is turned off, it is necessary to disconnect the generator from the battery.

During diagnostics, the relay is checked to perform its three functions:

Battery cut off when the car is parked
limiting the maximum current at the generator output
voltage adjustment for field winding

Any malfunction requires repair.

Alternator relay

Unlike the previous case, diagnosing the alternator regulator yourself is a little simpler. The design of the “automotive power station” already includes the function of cutting off power from the battery while parked. All that remains is to check the voltage at the excitation winding and at the output from the generator.

If the car has an alternating current generator, it is impossible to start it by accelerating down a hill. Since there is no residual magnetization on the exciting winding here by default.

Built-in and external regulators

It is important for a car enthusiast to know that they measure and begin to regulate the relay voltage at a specific location where they are installed. Therefore, built-in modifications act directly on the generator, while external modifications “do not know” about its presence in the machine.

For example, if a remote relay is connected to the ignition coil, its work will be aimed at regulating the voltage only in this section of the on-board network. Therefore, before you learn how to test a remote-type relay, you should make sure that it is connected correctly.

Control by “+” and “–”

In principle, the control circuits for “minus” and “plus” differ only in the connection diagram:

when installing the relay in the “+” gap, one brush is connected to “ground”, the other to the regulator terminal
if you connect the relay to the “–” gap, then one brush needs to be connected to the “plus”, the other to the regulator

However, in the latter case, another wire will appear, since the voltage relay is an active type device. It requires individual nutrition, so “+” must be supplied separately.

Two-level

At the initial stage, mechanical two-level voltage regulators with a simple operating principle were installed in the machines:

Electric current passes through the relay
the resulting magnetic field attracts the lever
the comparison device is a spring with a given force
When the voltage increases, the contacts open
less current flows to the exciting winding

Mechanical two-level relays were used in VAZ 21099 cars. The main disadvantage was working with increased wear of mechanical elements. Therefore, these devices have been replaced by electronic (contactless) voltage relays:

voltage divider made of resistors
The zener diode is the master device

Complex wiring and insufficient voltage control have led to a decrease in demand for these devices.

Three-level

However, two-level regulators, in turn, also gave way to more advanced three-level and multi-level devices:

the voltage goes from the generator to a special circuit through a divider
the information is processed, the actual voltage is compared with the minimum and maximum threshold values
the mismatch signal regulates the current flowing to the exciting winding

Relays with frequency modulation are considered more advanced - they do not have the usual resistances, but the frequency of operation of the electronic key is increased. Control is carried out by logical circuits.

Disadvantages of electrical equipment of the VAZ 2110

Where, exactly, do all the complaints about the battery come from? A good well-maintained battery will last five to seven long winters and no questions will arise about it if you charge it correctly, discharge it correctly and at least slightly monitor its condition. In the case when the battery is charged directly on board the car, which most often happens, the charging current strongly depends on the number of consumers on board.

The more of them, the stingier the generator becomes and pays less and less attention to the battery. He also needs to feed the voracious fog lights, a powerful audio system, additional comfort equipment, refrigerators, glass, mirror and seat heaters, and you never know what else the tuners come up with. And the generator is designed taking into account the rated charging current, without taking into account the additional load. As a result, the battery sits on starvation rations, is constantly undercharged, especially in winter, the plates crumble and after two years of grueling work asks to be thrown into a landfill. We blame the battery, of course. Only in vain.

Which TRN is suitable for LADA

Generator, article number	Automobile	TRG, article number
26.3701, 37.3701, 371.3701, 372.3701	VAZ-2107, -2108, -2109, -2110, OKA	67.3702-01
3002.3771, 332.3771, 3202.3771, 3212.3771, 4302.3771, 94.3701, 9402.3701, 9422.3701, 3740.3771-38, 3743.3771-61, 3747.3771- 93, eld-a-21214, LG01214	VAZ, GAZ	67.3702-02
4052.3701, 409.3701, PRAMO “ISKRA” 5102.3771, -10, 5112.3771, -10, 5122.3771, -10, -30, 5142.3771, AAK 5727	VAZ, GAZ, UAZ with generators PRAMO “ISKRA” 5102.3771, 5122.3771	67.3702-04
G222	VAZ-2104, -2105, -2107	67.3702-09
26.3701, 37.3701, 371.3701, 372.3701	VAZ-2107, -2108, -2109, -2110, OKA	67.3702-11
3002.3771, 332.3771, 3202.3771, 3212.3771, 4302.3771, 94.3701, 9402.3701, 9422.3701, 3740.3771-38, 3743.3771-61, 3747.3771- 93, eld-a-21214, LG01214	VAZ, GAZ	67.3702-12
generators with an additional three diodes, the excitation winding of which is connected to the positive circuit	673.3702

Standard regulator diagram

The usual voltage regulator circuit provides diodes of different levels. However, their barriers may differ significantly. This is primarily due to a sharp change in voltage in the system. The current should also be taken into account. Among other things, the regulators have radiators.

Their main task is to cool the diodes. The position of the device is directly controlled using a toggle switch. The voltage regulator circuit also contains an electric drive strip, which closes the circuit.

Dismantling and checking voltage regulators on a VAZ 2107

First, let's decide on the tools and devices that will be needed for the job. Here they are:

household multimeter;
open-end wrench 10;
flat screwdriver;
Phillips screwdriver.

Sequence of work

If the driver suspects that the voltage regulator is broken, then the first thing he should do is check the voltage supplied by the battery.

If it drops below 13 volts (or, conversely, rises above 14 volts), then this indicates a breakdown of the regulator.

Video: checking the voltage regulator on a VAZ 2107

Like any other device, the voltage regulator can break down suddenly. And it’s especially difficult for the driver if the breakdown occurs far from home. There is nothing surprising here: drivers who constantly carry spare regulators with them need to look further. But even in such a difficult situation, there is still a way to get home (or to the nearest service center). But you won’t be able to get there quickly, because every hour you’ll have to crawl under the hood and remove the terminals from the voltage regulator. And then, using a suitable piece of insulated wire, connect the positive terminal of the battery and contact “Ш” on the regulator. This is done so that the charging current does not exceed 25 amperes. After this, the regulator terminals return to their place, and the car starts. You can drive it for about 30 minutes, and you should turn on the maximum number of energy consumers - from the headlights to the radio. And after 30 minutes you should stop again and do the entire above procedure again, since without this the battery will simply recharge and boil.

So, even a novice car enthusiast can check the voltage regulator on a VAZ 2107. All that is required is the ability to use a multimeter and a screwdriver. Following the recommendations listed above will allow the car owner to save about 500 rubles. This is how much it costs at a car service center to check and replace the voltage regulator.

Source