Connecting the generator to the network of a country house

A gasoline generator or its diesel analogue, at their low cost, is the most suitable source of emergency power supply for a private home or cottage. Such installations are easy to transport and operate . The electrical installation of a gas generator, as well as its selection, requires a responsible approach. Incorrect connections can cause damage to household appliances or short-circuit wires in the house, not to mention it poses a danger to life. But if you know how to connect a gas generator to the home network correctly, you can restore the operation of electrical appliances quickly and safely.

Using a changeover switch

In fact, this is also a connection to a distribution machine, only without the need to disconnect the input wiring.
A three-position switch is mounted in front of the machine to avoid unscrewing the wiring. The task of this switch is to switch the network power from one branch to another (from an external network or generator). To perform this function, you need to select a switch with 4 input terminals (2 “phases” and 2 “zeros”), since the generator has its own “zero”, and a three-terminal switch will not work in this case. An alternative to a 3-position switch would be to install a pair of two-way machines next to each other, but rotated 180 degrees to each other. The keys of both devices are secured with pins through holes specially provided for this purpose. In operation, when switching the keys, for example, down, such a combination of machines will block the power supply to the network from the external line and open the way for the electric current generated by the autonomous generator. The opposite action with the keys will lead to the passage of current from the power line and blocking the flow of energy from the generator.

For convenience, such a switch should be installed in close proximity to the generating device, since it is launched in a certain sequence:

Direct start of the generator engine.
Warming up the device.
And only then connect the load.

Naturally, it is more convenient to perform these actions and control the process in one place.

To prevent the generator from running in vain, that is, when voltage is already supplied to the backup line, it is necessary to mount a terminal for the lamp in front of the switch. Turning it on will signal the need to turn off the autonomous source and switch to supplying electricity from the main power line.

Rules of use and safety

When using a gasoline generator, the following rules must be observed:

If the device is connected to very sensitive equipment, then it is necessary to use a voltage stabilizer.
If you use the mini-power plant frequently, you need to carefully monitor the degree of wear of certain parts and, if necessary, replace them.
If scheduled maintenance is planned, then it is necessary to use only those brands of fuel and liquids that are recommended by the manufacturer.
Do not store fuel in the tank for a long time. Its downtime can ruin the ignition of the gas generator, thereby reducing its service life.
Carry out switching on and off in the prescribed sequence.
When the generator is starting, it is better to have good lighting around;
If necessary, adjust the valves - the essence of it is that the valve clearances of the gas generator are set in a certain way.
Do not inhale gasoline fumes - they are harmful to health.
If fuel gets on your skin, be sure to wash it off thoroughly with soap and water.
Do not allow flammable objects near the device, and especially do not turn it on in an explosive environment!

How to properly connect a generator to the home network

Connecting a power plant to your home network is possible in several ways. A popular option is to connect the network reserve through a changeover switch or packet switch.

How to connect a generator to the network at home

For the case of automatic connection of a power plant with auto-start, an ATS system (automatic transfer of reserve) is used. It is also possible to connect various household appliances through an extension cord with several sockets. In this case, the extension cable cross-section is calculated based on the total load current.

Installation of a changeover switch

The easiest way to connect an electric generator to your home is to install a changeover switch or packet switch. The batch switch is installed on a DIN rail in the electrical panel of the house. The switch is placed near the electrical panel.

The external electrical network is connected to the upper contacts of the switch, and the lower contacts are used to connect the cable from the power plant. The middle pins connect the home network input. After installing and connecting the changeover switch, put on the protective housing.

Connecting the generator through a switch and automatic transfer switch (ATS)

It is recommended to connect the switch after the electric meter and before the water dispenser. When the mains voltage disappears, the generator is started. After the engine has warmed up, the changeover switch is moved to the lower position (to the contacts going to the generator). After the network appears, the switch is moved to the upper position and the power plant is turned off.

Connecting the power plant via ATS

For automatic control of the power grid and automatic transition to a backup generator in the event of a network failure, there is an ATS device with automatic start-up of power plants. The AVR system monitors the electrical network and, when it disappears, disconnects the magnetic starter from the network and turns on the autostart of the generator.

When the generator reaches its rated speed, another magnetic starter is turned on, which connects the home network to the power plant. When the network is restored, the ATS disconnects the home network from the generator and connects another starter to the external network.

Connecting a 3-phase generator to a three-phase network at home

This transition from the backup generator does not occur immediately after the network appears, but with some time delay until the external network becomes stable. For the case of three-phase networks, it is recommended to install a single-phase generator, and connect all necessary household appliances and equipment to it via a separate backup electrical wiring with a changeover switch.

In a private home, AVR does not always pay off, since it always has to be controlled. With the same success, you can use a changeover switch and start the power plant manually. It is recommended to use a switch in case of rare outages of the external network.

Power plant grounding

For electrical safety purposes, in cases of voltage breakdown on the generator housing, a grounding connection is required. For power plants, you can make a simple ground loop. A piece of steel pipe, a pin or a metal rod with a diameter of 20 mm and 1.5 meters in length, is driven completely into the ground.

Generator grounding

At the end of the grounding conductor it is necessary to weld a bolt for the grounding conductor. As a conductor, a copper stranded flexible wire of 4-6 mm², with external insulation, is used.

The installation location of power plants must be selected taking into account fire safety, noise, precipitation and room temperature.

A simple way to organize auto switching

In order not to manually switch the switch every time there is no electricity supply from the main power supply line of the household, you can make a fairly simple circuit that allows you to automatically switch from an external network to an autonomous one after starting the gas generator.

To install an auto-switching circuit, you will need two starting devices (contactors) that have a cross connection. During their operation, power as well as normally closed contacts will be involved. In addition to this set, if you need to provide the generator with a certain period of time for warming up, it is worth purchasing a time relay.

When voltage is created in the home electrical network from an external line, the main input contactor coil will keep the power contacts in the closed state, and the normally closed ones, on the contrary, in the open state.

When the voltage in the power transmission line disappears, the power contacts will open, and the normally closed ones will, accordingly, go into the closed state, which will allow, after a period of time specified by the temporary relay, after the generator is started, to supply voltage to the coil of the backup input contactor. As a result, the power contacts on the backup starter will close, and electric current from the gas generator will flow into the home network.

You might be interested in: Number and layout of sockets in the kitchen

When the centralized supply of voltage to the network of a private house is restored, the coil of the main starter will work, which will lead to the closure of the power contacts of this contactor and the automatic shutdown of power from the gas generator. The owner of the house just has to remember to stop the engine of the device for autonomous generation of electricity.

Through an automatic (distribution) switch

The ideal option is if the panel has an outlet. This method should not be confused with the one described above. On the electrical goods market, some ready-made panels are initially equipped with such outputs (it is recommended to choose them for private households). Sometimes, when assembling the panel yourself, they install an incoming AV, a meter, an RCD and one or two sockets for insurance, so it is convenient to carry out repairs. Then the generator can be connected there without any problems.

You need to be reliably aware that this is not an ordinary power outlet.

The rules must be followed:

the socket must pass at least 16 A or more under the power of the backup device;
AV at the input must be disabled.

If the described elements are not in the shield, then remove the input wires from the switchboard and connect the device directly to it. If RCDs and RCBOs are further installed, the polarity must be observed. Let us remind you: if you connect to the “firefighter” AB in front of the metering device, the circuit will work, but the meter will count its own electricity already produced. The introductory AB is sealed by energy sales, so more often than not the possibility of this option is completely absent. It is necessary to choose exactly the distribution (group, common) AB or RCBO after the metering device.

Algorithm of actions:

Turn off the input machine. After connecting the backup source, it can be activated again, and this will be necessary before installing the control lamp.
Unscrew the clamps on the switchgear terminals and remove the wiring.
In place of the indicated cores, observing the polarity, especially if further than the RCD, RCBO, connect the cores from the generator cable.
You can mount a light bulb on the folded wires, which will indicate the resumption of the main power supply; after installing it, the introductory circuit breaker is turned on.

Gasoline generator and its connection

Initially, it is worth understanding that if a person does not have certain knowledge and skills in connecting and operating such mechanisms, the task will turn out to be too difficult. It would be better not to touch any of the cables or other parts of the system at all, without first consulting with a specialist in this field. Otherwise, you can not only harm the communication system, but also your own health.

By turning to more experienced people for help, anyone who has started installing such a unit will understand that in the end the work will not take much time and effort

It is critical to follow the established installation procedures when performing tasks.

Stages:

Initially, you need to select a room or specially separate part of the room to equip it with a generator. The main characteristics that should accompany this part of the building are good sound insulation and constant ventilation. Before you begin installation, you must carefully study the information specified in the device data sheet and familiarize yourself with the detailed technical specifications.

Important! Safety is the most important thing when choosing a location for equipment. It must be used under proper conditions

Next you need to run the wires from the generator to the panel.
The gasoline sample unit is installed only if there is a changeover switch in the system.

The last point plays a special role. It is mandatory because it has three main ranges - 1-0-2. How it works:

If there is voltage, the switch is in mode – 1;
If the power is turned off, you need to turn off all the machines in a certain order, move the switch to position 0, and then to mode 2.

After following these instructions, you can start turning on the unit.

As soon as the electricity is turned on, you should immediately turn off the gasoline generator. It should not be used for too long. On an electric meter it is quite easy to determine when voltage appears - a special diode begins to glow. While it is turned off, there is no electricity in the network.

Switch Connection

The simplest way to connect a generator is using a switch. The switch operates in three positions. In the initial position, the object is connected to a centralized power grid, without the participation of a gas generator.

When the switch moves to the next position, the object is completely de-energized. The next time you turn the switch, the power to the home network switches to a backup source - a gas generator.

Keep in mind that if the total power of all consumers is 6 kilowatts, then the switch must support at least 30 Amps.

We do not recommend:

Ground one of the generator outputs to the common house PE bus (ground). If your ground “falls off” (a wire rots or a connection comes loose), dangerous voltage will appear on all grounded appliances in your home.
Connect budget generators directly to the load without using network interference filters. Changing the generator speed causes strong interference and voltage surges, which are dangerous for sensitive electronic equipment (automatic gas boilers, expensive household appliances).
Use three-phase generators with a power of up to 10 kW for backup power at home. Phase imbalance will lead to rapid failure of the generator. Use single-phase generators with a phase combination circuit.
Connect inverter generators to a common neutral bus. This can lead to rapid generator failure.
Neglect the rule of grounding the generator housing itself.
Use a non-inverter generator without a solidly grounded neutral of one of its outputs, because this leads to incorrect operation of differential protection devices (RCDs) and errors in the operation of phase-dependent boilers.
Use the generator output for grounding, which is turned off by a single-pole circuit breaker on its body.

We’ll talk about how to properly connect a generator to the network (220/380V) of a country house later.

Choice

The buyer must determine from the very beginning which technical parameters are the most important for him. It is worth taking a closer look at these indicators:

Weight.
Dimensions.
Power.
Fuel consumption.
Noise level.
Duration of work.

Automation and price are parameters that are also being looked at

This is important for those who are interested in how to connect a generator to the home network, the diagram of which is posted on specialized websites

Generator operation

By parameters

Many people first look for an answer to the question of how many phases a generator should have for maximum convenient operation. To do this, you need to understand what electrical appliances will be connected. Three-phase options allow connection to both single- and three-phase devices. Single-phase ones are combined with only one type of consumer. But this does not mean that models with more phases will be better under all circumstances.

At each phase, the maximum load should be no more than 30%. This means that in reality the owners will not be able to use more than a third of the rated power that the outlet initially has. For example, the rated power of a three-phase generator is 6 kW. This means that no more than 2 kW can be removed from a regular 220 V outlet. The load still needs to be distributed over several phases when connecting a single-phase generator to a three-phase network at home.

Note! For power, they also check the parameters of the devices that are planned to be connected

It is important to have a reserve of at least 20-30%. Otherwise, you may encounter problems such as overload and work stoppage. Too much fuel will also be consumed

Too much fuel will also be consumed

Otherwise, you may encounter problems such as overload and work stoppage. Too much fuel will also be consumed.

Type

Synchronous and asynchronous types of devices are available. The choice involves a careful study of the characteristics of each of the existing models.

Asynchronous

Their main problem is their inability to handle so-called peak loads. Although these devices can also be used to maintain normal voltage readings. They are suitable for joint use with equipment sensitive to voltage surges:

Electronic devices.
Computer Engineering.
Medical devices supporting gasoline generators.

Residual magnetization of the rotor is the main source of energy for such devices. Therefore, the service life of asynchronous generators is longer than that of their closest analogues. They do not require the use of cooling systems; the unit housing is completely closed. Thanks to this, protection from dust and moisture is fully guaranteed.

Interesting! The asynchronous generator is immune to short circuits. Therefore, this energy source is the optimal solution for welding machines. But such devices can be very sensitive to overloads. Therefore, it is prohibited to connect them to devices with initially high inrush currents.

Synchronous

The quality of the current in this case is lower when compared with the previous option. Suitable for providing emergency power in various circumstances:

Offices.
Refrigeration units.
Electrical equipment in dachas and country houses.
Construction projects.

Such devices also have some positive qualities:

Resistance to short-term overloads.
Ability to normally withstand peak loads, including mechanical loads.

But protection from moisture, dust and dirt is worse than that of asynchronous structures. After all, in order to cool, such generators need to pass a certain amount of air through themselves. A synchronous generator will be needed if devices operating with reactive loads are used. Then the power will be less.

Changeover switches

Phasing

It has already been mentioned above. It is worth buying three-phase generators only if there is a consumer with the appropriate characteristics in the house. If all the devices are single-phase, then the generator is selected of this type. This even applies to situations where there is a three-phase network connected to the house.

Network connection

Difference between single and three phase connection

All connections, whether in a single-phase or a three-phase network, are made completely identical, with the exception of the number of power wires. The only important nuance concerns the so-called control phase - if you connect the starter to the network, then its main contacts connect and disconnect the power wires from the network, and the power for the electromagnetic coil must also be taken from somewhere.

In a single-phase network there are no problems - there is only one phase and such a question simply does not exist, but in a three-phase network everything is somewhat more complicated - there are L1, L2 and L3. Without going into technical details, there is only one answer - for control circuits you can use any of the phases, but only one. That is, if the KM1 coil is powered from phase L3, then the control of the remaining starters, the “Start” and “Stop” buttons must also be “hung” only on it. This is not difficult to do - just note what color the wire is on the desired phase, and if the cable has single-color conductors, then stick or draw markers on them.

How to connect the generator?

The electric generator can be connected in two ways:

Through a switch (connection to the panel);
Using automatic or semi-automatic reserve input.

The generator is connected to the panel using a changeover or reversing switch:

Before installing it, a cable is laid, depending on the power of the generator.
Then the switch itself is installed in the panel in a special box, protecting it from rust and corrosion.
After that, all that remains is to connect the switch (the main network cable is located on top, the private circuit of the house is in the center, and grounding is below), and start the generator.

Connecting a generator with a semi-automatic automatic transfer switch involves installing two semiconductors in protective boxes that are connected to each other. When the lights go out, you need to start the backup power source, then there will be an automatic transition from the main network to the generator.

Automatic reserve input means turning on the generator automatically, without any intervention.

Generator switching sequence

The main secret of safety is in following these simple rules for turning on the generator. I hung them in front of the counter so I wouldn't forget. Besides, I may not be at home, my wife will turn on)

If there is no light from the street

1. Turn off ENTER (automatic 1)

2. Go to the generator, connect it to a special outlet.

3. Check that the load switch on the generator is turned off. Also, make sure that all heavy loads in the house are turned off.

4. Start the generator, let it warm up and go into operation for at least 30 seconds.

5. Turn on the machine on the generator.

6. Turn on the required load one by one.

If the light was given

1. The appearance of voltage on the street line is indicated by a red indicator under the meter.

2. Turn off the powerful load

3. Turn off the generator, turn off the load switch at its output.

4. Pull the generator plug out of the socket.

5. Turn on the introductory machine No. 1.

What types of generators are there?

Many people think that generators and uninterruptible power supplies are mutually interchangeable and identical. But that's not true. UPS are devices that provide current only for a while. Their work is just enough to save important information on the computer, for example. The generator can produce electricity many times longer.

There is another device that many also confuse with generators. These are voltage stabilizers. They equalize the voltage if surges occur in the network. Stabilizers protect equipment from sudden changes in network voltage, thereby extending the service life of electrical appliances.

Before answering the question of how to connect a generator to the home network, you need to understand which generators can be connected to the home network.

There are three main types of generators based on engine type:

gasoline;
diesel;
gas.

A gasoline generator is used only for a short time; its operation is not suitable for long-term loads. If the main power source is, then gasoline units should be purchased only to maintain the operation of the devices for a short time (up to 12 hours), if there are frequent network outages.

The diesel generator is the most powerful unit. This is, in fact, a diesel station that can continuously generate electricity, or be used as a backup generator for lighting the house.

Gas generators consume the least amount of fuel, which is why they are considered the most economical generators. They can operate either from a gas cylinder or from a gas main.

Also, both gas and gasoline can be used as fuel in one generator - with the ability to switch. They are called dual-fuel.

There are two more types of generators - inverter and welding. Both gas and gasoline can be used as fuel.

Inverter generators have a distinctive feature - performance adjustment. For example, during a power outage, all appliances in the house are connected to the generator. If you turn off any device, automatic performance adjustment will work, and the generator itself will reduce the load.

Welding generators are designed to power welding machines, mainly manual ones.

The number of phases and the cooling system also depend on the type of generator.

Based on the number of phases, generators are divided into single-phase (output voltage 220 V) and three-phase (380 V). The first are used in residential buildings where there is only one power and ground line. A three-phase generator provides power via three power lines, with one grounding line.

Generators use air or liquid cooling. The first is used on generators or power plants whose power does not exceed 6 kW. Liquid cooling is installed on more powerful generators, the number of engine hours of which is about thirty thousand. It is better to buy such generators on official websites or in specialized stores to prevent interference with the device by unscrupulous sellers.

How to connect a three-phase generator?

In the case of using a switch, a winding is required for each phase separately, that is, a jumper from one phase to another.

How to make a gas generator with a ready-made power plant?

The answer lies on the surface - connect the generator to a gasoline engine. Where can I get it? Any electric motor, with the correct organization of the winding excitation system, becomes a generator.

DC generator

It receives torque from your car's engine and produces 14 volts of DC voltage.

There is no need to invent anything. Just look at the power characteristics and select a small engine from those listed above.

The main condition is a working voltage regulator and preferably “live” windings. However, if you get a burnt copy, it doesn’t matter. Any radio amateur knows how to remove the anchor from the electrical installation of a gas generator.

You can rewind the winding in one evening. In principle, if you can assemble a mini power plant yourself, you can sit down to write a book: “Gasoline generator malfunctions and ways to eliminate them.” This is an extremely useful experience.

A breakdown of a power source in an open field is a problem. And someone familiar with the Kulibin device will be able to restore operation without calling a technician.

The only drawback, however, is significant - the voltage is 12-14 volts. Lighting, charging mobile devices, connecting music and computer - no problem. But for the home you need 220 volts. A voltage converter will help out, for example, from an old uninterruptible power supply.

AC motor

Here the situation is more complicated (albeit cheaper, there is no need to look for a converter). Any electric motor can be turned into a generator by connecting it to a drive.

There are nuances. To excite the windings in generator mode, a capacitor circuit is required (see figure) and precise selection of speed.

If you have read this far, there is no point in explaining how to get one 220V phase from a 3-phase 380V source. This is the topic of a separate article.

To measure revolutions you will need a tachometer. You connect the motor to the network and measure the rotation speed. Add 5%-10% to the obtained revolutions, and you get the optimal shaft rotation speed for exciting the generator windings.

Homemade 220 volt gas generator from a GAZ 21 engine and a 15 kW alternator - video

Automatic generator start via AVR unit

The purpose of such devices is to partially or completely eliminate human participation in the operation of the generator. There are two main types of such devices. The first completely copies the auto-switching system, which operates on two starters, but with the addition of an electronic unit for starting and stopping the generator. A low-current cable is connected to it from the main power supply line, through which the unit receives information about the presence or absence of voltage in the network. Depending on this, it sends a command to the engine to start or stop, and switching between input from the main line or from the generator is performed by the starters themselves. In general, this is the same system as the proposed scheme for self-assembly, but here you don’t have to invent anything - just install a ready-made unit.

The disadvantage of such a block is the same - its purpose is only to start and stop the engine without additional protection.

The diagram itself looks like this:

1. Introductory machine. 2. Electricity meter. 3. Automatic generator start block. 4. Generator. 5. Time relay. 6. RCD. 7. Main input contactor. 8. Backup input contactor.

A more advanced option is a complex system controlled by microprocessor electronics. In general, it works in the same way as a homemade autostart system, but its main advantage is the presence of numerous sensors that monitor all aspects of the generator's operation. If any equipment malfunction occurs, the ATS unit will be able to react adequately - not torment the generator with autostart attempts, but if there is a GSM module, send a message to the owner about the malfunction.

The ATS unit itself is mounted instead of a distribution panel - this does not require much knowledge - you just need to connect wires from the main line, power and control cables from the generator and output to the house to it.

1. Introductory machine. 2. Electricity meter. 3. AVR. 4.Generator. 5. Control cable. 6. Consumer machines. 7. Zero bus. 8. Grounding bus.

Such a unit is a complex set of equipment and its cost in some cases can be equal to the price of a generator. Therefore, its purchase is justified only in case of frequent power outages and for sufficiently powerful generators.

Automatic switching with autostart

From all of the above, it is clear that it is impossible to completely automate the process of switching a house from the network to a generator using simple methods using two or three parts. But it’s too early to give up, since such systems not only exist, but are also quite accessible. Their name is AVR - Automatic Reserve Entry. Such units can come complete with gas generators or be purchased separately.

Their cost, of course, is quite high, but ATSs allow not only to truly automate the process of switching to a generator, but are also able to perform some other functions. Below are just the main ones:

Automatic disconnection from the main network in the event of a power failure.
Starting a gas generator with an alarm for a failed start.
Switching to power from the generator only when it reaches operating mode.
Monitoring and automatic adjustment of voltage and frequency depending on the load.
Overload and short circuit protection.
Engine hour counting.
Switch to the main source when power supply is restored.
Generator stop.
Recharging the starter battery.

As you can see, the list of functions performed by the ATS is quite wide, but, unfortunately, structurally it is also very complex. Today, almost all such devices contain microcontrollers, and only a specialist with the appropriate knowledge and experience can assemble an ATS with his own hands. That is why the independent production of a full-fledged autostart system will not be considered in this article.

General block diagram of connecting a generator to a country house network

Grounding

The very principle of operation of the generator involves the periodic occurrence of static electricity on its body, therefore all permanently installed devices necessarily require a separate grounding circuit.

The ideal option is to create a full-fledged grounding loop, but in general you can get by with the simplest method, for which you will need a metal rod 1.5-2 meters long, a steel bolt or clamp connection and a soft copper wire. A bolt is welded to the iron rod, and the pin itself is driven the entire length into the ground. The copper wire is screwed with one side to the bolt (or clamped with a clamp), and the other to the generator housing - the grounding is ready.

These are all the main ways to connect a gas generator to the network at home and possible nuances. The presented diagrams will help determine whether it is worth installing autostart systems or whether it will be easier to do with manual switching. Of course, when installing each individual generator, ATS unit or homemade autostart system, additional questions may arise, but they will have to be resolved in each case separately, depending on the device model and the home electrical circuit diagram.

Switches are required

Having a separate switch, although it will be used infrequently, will make the home's electrical circuit safe for both users and the equipment connected to the power supply. Although the simplest solution is a regular outlet through which you can power the entire home network. Moreover, the connection to electric generators is also made through sockets installed on their housing. However, everything depends on the power of the electric generator.

If its power is more than 2-3 kW, a regular outlet may overheat and become unusable. But even more powerful contacts will only partially solve the problem. For an optimal scheme, emergency load shedding is necessary. There will also be a high probability that when mains voltage is applied, there will be a back-to-back connection between the generator and the supply network. And this can lead to damage to the electric generator.

The changeover switch, although not automatic, in one of its three positions will redirect consumers to the electric generator. Moreover, a counter connection will never work, since this is physically impossible in this switch. In the middle position, the home electrical network is de-energized. Even when the electric generator is running and there is voltage in the mains, you can switch between these two sources of electricity without problems.

Connecting a reversing switch in a single-phase electrical network

The blue wire of the network and generator (see image above) must be passed through the contacts of the circuit breakers. The network and the electric generator need their own separate circuit breaker. The generator connection diagram must include a grounding loop or grounding from a pipe or steel profile with a length of 2 meters. A good grounding option is a water well pipe.

If the house is connected to a three-phase network and the electric generator is single-phase, the circuit shown below is recommended.

Connection diagram of a single-phase electric generator with a three-phase home network

In conclusion, we will give our own recommendations for choosing a generator connection diagram. Let us remind you once again that you need to start building such a scheme from the statistics of power outages in a specific place. Manual switching to an electric generator is cheaper. Also a cheaper option is to use uninterruptible power supplies for specific equipment. An electric generator is most effective when heating with electricity when outages are regular and long.

UPD: Connecting the boiler to the generator.

Often a generator is purchased to be used in winter to power the heating system boiler. There are some peculiarities here.

For imported phase-dependent boilers, it is important that the power system has a solidly grounded neutral, i.e. neutral and ground are connected together, and when connecting, the polarity is observed (phase-zero)

In the case of a portable generator, which is discussed in the article, there is neither zero nor phase. They must be made artificially - one output of the generator will be a phase (L2), and the second (N2) will be placed on the ground, i.e. ground.

In addition, as is known, boilers are very sensitive to the voltage form. And at the output of a conventional generator, the sine wave is “dirty”; if necessary, I will take an oscillogram. First of all, this happens because... The alternator that generates electricity is brushed, and because of the brushes sparking, failures, and similar unpleasant things occur.

It is because of this that Off-line and Smart UPS are not suitable for boilers. There at the output there is a quasi-sine with a bunch of harmonics, the oscillograms can be viewed here. And for boilers, Online UPS (double conversion uninterruptible power supplies) is used. For such a UPS, the shape, magnitude and frequency of the input voltage are not particularly important, because it cooks a constant voltage from all this mess, from which it then electronically receives a pure sine wave. And if the boiler is powered through such a UPS, then you can use a regular generator for its backup power.

For boilers and other sensitive equipment, it is recommended to use inverter generators - this is a generator plus an online UPS. The inverter generator includes a regular generator, which is controlled by a controller, and an inverter, which produces pure sine wave - what boilers need.

Classification of gasoline generators

The gas generator can operate according to a synchronous or asynchronous scheme. In a synchronous type generator, the rotation of the starter's magnetic field is identical to the rotor.

Such a unit responds faster to power surges and provides smooth power thanks to the inductive coils on the rotor (fluctuations do not exceed 5%). Such generators are more expensive. The equipment is sensitive to moisture.

The rotor of an asynchronous generator is hidden in a sealed housing. Unlike a synchronous device, it is more protected from adverse natural factors. The rotation of the rotor and starter in asynchronous installations does not coincide.

The rotor is ahead of the starter. When the load changes, the voltage sags, which is unacceptable in the operation of a gas boiler. The equipment is not recommended for use to power high-precision instruments.

The automation unit will allow you to start the generator on time without human intervention. Even if the owners are absent when the lights go out, the heating will not freeze

The equipment also differs in the way it is turned on. The unit is started manually. After the power supply is restored, you need to turn off the device yourself. Automatic models spontaneously react to power outages. Shutdown also occurs autonomously.

The device for providing uninterruptible power supply can be frame and inverter. Frame models are most widespread in everyday life. They are distinguished by their large dimensions (from 60 cm) and solid weight (from 40 kg).

Frame gas generators are recommended for stationary use. Due to the impressive weight, it is unwise to move this type of equipment for one-time power supply.

Inverter models are more compact than frame models. They are recommended to be used for power supply of complex electronic devices, the operation of which depends on voltage stability.

Inverter gas generators are compact and light weight. They are easier and more convenient to connect to a heating unit as needed and use to solve various problems

The equipment is divided by phase. The voltage in a single-phase generator is up to 400 Watt. They are used to power several household appliances simultaneously.

Three-phase generators cannot be operated at low temperatures due to the fact that the oil in them instantly solidifies. Under suitable conditions, the equipment can operate for up to 10 hours.

Distribution board diagram with a “network-generator” switch

Details Published: 04 June 2015

In dacha areas, garden plots, the private sector and similar places, frequent power outages are common. Here they can turn off the lights for an hour, for the whole day or for a longer time. This creates quite a few problems, since people can no longer imagine life without electricity. He has things working at home: a refrigerator, a TV, room lighting, a pump for watering the garden, and the like.

Gasoline power plants are very popular in such places. Turn off the lights, start the gas generator and continue to enjoy life. The power plant must be connected to the distribution board through a special outlet. Below I look at the diagram of a distribution board with a “mains-generator” switch, which allows you to switch to power supply from a gas generator when the external network is lost and back.

Here I am considering manual switching, which is carried out using a reversing switch. All diagrams show an ABB OT40F3C switch. This is a high-quality and reliable reversible switch. It has three positions:

the handle is turned to the left - the contacts on its left side are closed, and on the right side they are open;
the handle is in a vertical position - all contacts are open (both right and left);
the handle is turned to the right - the contacts on its right side are closed, and on the left side they are open.

If what is written is not entirely clear, then look at the latest diagram and you will immediately understand how it works.

It is worth noting that if you take such a reversing switch for a higher current, then the switch handle is not included in the kit. It must be purchased separately.

Below is a simple single-phase switchboard diagram with a mains-generator switch. This is plenty for a small dacha or garden house. If you have a large house, then you need to revise the ratings of the input machine and increase the number of group lines. Everything is individual here.

It is very convenient to use a network indicator in such panels. For example, the signal lamp LS-47. Why is she needed here? Let's say the lights are turned off and you start the power plant. Everything is working.

Next, how to determine whether there is voltage in the network or not? You won’t run to the switchboard every half hour and use an indicator to check whether the light is on or not. This is not convenient and is forgotten over time. So you can miss this moment and “sit” on the gas generator until the evening. And gasoline is expensive these days.

In such a situation, the mains voltage indicator will immediately show you when the light comes on

It will just light up and you will immediately notice it. It is clearly visible from afar even through the transparent cover of the shield. As soon as the warning light came on, they immediately turned off the power plant and switched the switch to mains mode

As soon as the warning light came on, they immediately turned off the power plant and switched the switch to mains mode.

Below is the same diagram of the distribution board, but with an LS-47 signal lamp.

If you want to protect yourself and your dacha from current leaks, then you need to install an RCD. Below is a diagram with one common protective device. If you want more, then go ahead and fight. Here you can fantasize endlessly.

For a better understanding of the operation of such a circuit, I schematically showed the state of the contacts of the reversing switch with red lines and the direction of the current with red arrows.

Below is the work from an external network.

And here the work from a gas generator is already presented.

And these are already two diagrams of the operation of this switchboard in one. It looks like a cartoon. Like?

At the request of site visitors, I am posting below a 3-phase electrical panel diagram with a “network-generator” switch

Also don't forget to smile:

A drunk man goes home and hits his head on every lamppost. Then an acquaintance meets him and asks: “Why are you hitting the pillars like that, why are they bothering you?” Can't get around? “That’s not the point at all, it’s just how I determine the way home.” - Didn't understand. - What’s incomprehensible here? Here are 3 more pillars along this street, then 7 more along another - and I’m home.

Switching manually is at least cheaper...

When the electrical network already exists and it is necessary to connect automation to it to control the electric generator, difficulties arise that are difficult to overcome. Therefore, when modifying your home electrical network, it is better to choose a circuit with manual switching. To do this, in an electrical panel that is already in use, an option is used to install a changeover switch. It is best to use compact models of this switch. Some of them are shown below in the image.

Changeover switches from ABB

But they can only be used if all the necessary cables have already been laid to the electrical panel, or they can be laid under existing conditions. And, of course, a place is needed on the DIN rail to place the switch. Let us also clarify that such a switch belongs to expensive switches. Therefore, based on prices, we can instead recommend a switch of a classic design, shown in the image below.

Switch with switch

This switch is installed between the electricity meter and the distribution board. Where exactly is determined in each specific case. But the most important thing when choosing switching equipment is that it makes no sense to invest in expensive components. Backup power operates randomly and most often for short periods of time. Redundant switches perform a small number of switches. That is, they wear out minimally. Therefore, the simplest option is a circuit with a changeover switch.

Circuit with changeover switch (3 phases with common neutral)

Connection diagram of a single-phase generator to a three-phase network

Let's consider the key points of connecting a single-phase generator to a three-phase network. Recently, this topic was created on the forum, and I decided to give a more detailed answer, as well as discuss this issue on the blog, since many readers do not visit the forum.

Connecting a single-phase generator is relevant for private houses and cottages that want to have an independent power source.

Many luxury houses (cottages) have three-phase input due to high power consumption. Here the question may arise: what kind of generator is needed? A three-phase generator of the required power suggests itself.

Generator for a private home

Is a three-phase generator really necessary?

I will not give a definitive answer to this answer, however, I assume that a single-phase generator will be cheaper than a three-phase one.

I have already told you why three-phase input is bad. The main problem is that it is very difficult to achieve uniform phase distribution. Perhaps the generator does not tolerate operating modes very well when there is constant phase imbalance.

But how can we convert our three-phase shield into a single-phase one?

Everything is very simple. Scheme for automatically connecting a single-phase generator to a three-phase network:

Connection diagram of a single-phase DG to a three-phase network

For this we need only 2 contactors, not counting the auxiliary elements.

In normal mode, consumers are connected to a three-phase network through the KM1 contactor. If the main power is turned off, the generator starts. Starting can be done using the additional contact of the KM1 contactor. Contactor KM1 is turned off, and contactor KM2 is turned on and combines phase 3 into one.

If you do not need automatic starting of the generator, then instead of this ATS you can use, for example, a cam switch for the appropriate power. The connection diagram is similar to KM2. Here we must use either two manual switches or 1 switch, and turn off the supply network with an input circuit breaker.

Which solution is preferable? The choice is yours.

I also advise you to review my old articles:

I recommend reading:

“Scheme for connecting a single-phase generator to a three-phase network”

“At the same time, do not forget that the power of a single-phase generator will be at least 2 times greater than a three-phase one.”

They didn’t write about the zero cross section.

I don't understand the question about power.

The cross section of the zero is not less than the cross section of the phase wire. For example, VVG-3×16.

Why will the power of a single-phase generator be at least 2 times greater than a three-phase one?

About zero. Which cable to lay from the automatic transfer switch to the distribution board with a three-phase input with a power of 15 kW. Emergency diesel is acceptable at 15 kW.

Single-phase diesel respectively.

You calculate the current, select the machine, and then select the cable cross-section. At 15kVA - VVG-3×16

But then how will there be power from the network in three-phase mode?

The supply cable from the three-phase network will be your own, for example SIP4-4×16 or SIP4-4×25.

from the support to the ATS and from the diesel engine to the ATS everything is already clear. What kind of cable is placed from the AVR to the distribution board? And why is the power of a single-phase generator 2+ times greater than the power of a three-phase generator?

After AVR, you will have group lines. There should be no intermediate shields.

When you transfer all electric motors to one phase, the total Kc should decrease, therefore the power of the single-phase generator will be Pantryk:

There should be no intermediate shields.

If the ATS is built into a panel with group devices, then yes, there will be devices right away. And if the AVR is a separate design. It includes two cables (one from the diesel engine and one from the support) and one goes to the panel with group devices. So I’m talking about the zero of such a cable. Or for example, I have a two-story mansion and the allocated power is 30 kW, and I set the diesel to the same 15 kW. At the same time, I have a switchboard for the second floor. It is three phase. It comes with a 5x4 cable. And now we apply common-mode voltage to all phases. What happens to zero? In the particular case with one input distribution board, nothing bad will happen because The tire section is quite sufficient

But in the general case of using a single-phase generator in a three-phase network, it is worth paying attention to the zero cross-section in three-phase cables and groups

I did not consider all the nuances in detail, and did not become attached to a specific object. We always need to look at what currents we will have and, depending on them, select machines and cable sections.

If you have a project, we can discuss it in more detail on the forum.

Gas generator connection single and three-phase

The connection diagram for a three-phase power generator to a house or dacha in the presence of the same network implies similar connections as with a single-phase system. The only peculiarity: it is necessary to make more connections, since in this case the number of wiring strands is increased.

There is an important nuance: if you use a starter, then its contacts are intended for power wires, they will not be enough for the coil, you need to decide where to get the power for it.

Connecting a single-phase generator to the same network does not have the described complexity - there is only one phase, such a question simply does not arise. With three phases - L1, L2 and L3 - everything is more complicated. The solution is briefly simple: for the control circuit it is permissible to take any of the phases, but only one. For example, if the KM1 coil is powered from L3, then the control for the remaining starters, the start/stop keys, is also “hung” only on it. This is easy to do: mark with a marker or remember the color of the wire with the desired phase

We will consider phase mismatch briefly, since this is a separate topic. Connecting a three-phase gas generator to a single-phase network is possible, for example, using one of the power cores and a working zero. But the power is reduced by 3 times, and gasoline is consumed as usual. And if you separate 3 single-phase connections, phase imbalance may occur. Therefore, more complex schemes are used.

Connecting a single-phase generator to a three-phase home network is also possible. There are many schemes, but the simplest is this: parallel combination of 3 phases and connection to 1 phase of the power plant. At each phase the load will be distributed evenly.

Selection guide: you definitely need to buy a three-phase generator if the house has one and three-phase consumers at the same time, which often happens in private housing. Usually the product has a 380 V and a 220 V socket, that is, it can simultaneously power two types of devices.

Grounding

It is necessary to ground the backup source - a static charge arises on the case. It will be necessary to construct a separate grounding loop. It is ideal if it is possible to create a full-fledged structure, but a simple method is also suitable. You will need a metal rod 1.5–2 m, a bolt or clamp (metal), soft copper wire (large cross-section from 4 mm²). The core is connected with a clamp to the pin. Or they weld a bolt and attach it to it. The rod is driven into the ground, the other end of the wire is fixed to the generator housing.

So, the presented diagrams will help the user decide whether it is worth assembling autostart systems, buying an automatic transfer system, or getting by with manual start.

Which battery should I put on the generator so that the station starts up without problems in the cold?

Elektron72

If the generator is standing outside in the cold, then I recommend replacing the standard gel battery with a regular car acid battery of higher capacity. To charge the battery, if the ATS (automatic transfer switch) does not have its own charger, connect an ordinary 2-3 A switching power supply and set it to 13.7 V.

At temperatures of -30 degrees Celsius and below, almost all gasoline generators do not start or start with difficulty.

If you want a guaranteed start of the station in severe frosts, take a car battery with a capacity of 55-65 Ah. Or place the generator in an insulated and heated place.

Gen_Master

For a gasoline engine, for a confident start in the cold, it is important that the air filter is clean, the fuel is fresh, the battery is charged, the spark plugs are not flooded, and the oil is selected according to the season.

Why do you need to turn off the generator engine by closing the fuel supply valve?

Listen to the advice of a portal user who professionally maintains power plants.

Genmos

Most often, the generator does not start due to a malfunction of the fuel system. Therefore I recommend:

Keep the carburetor dry.
Turn off the generator by turning off the fuel valve until all the fuel is used up.

This way, there will be no gasoline left in the carburetor, and the electrical part of the station will cool down more evenly. This is especially useful for three-phase generators. How many times has it already happened? The client bought the station about 5 years ago. I filled the tank with gasoline. Never started the generator or changed the fuel. The lights were turned off, but the generator would not start. A man calls me and asks what should he do? And every time, the reason is in the carburetor and in the fuel system. To maintain the generator’s combat condition, I advise:

Start it once a month and run it under load for 30 minutes.
Turn off by turning off the fuel valve.
Change the oil according to operating hours or once a year.
When purchasing a new generator, run it at 50% power.

Important nuance : in winter, it is not recommended to keep the generator tank half empty or leave fuel at the bottom. Fill the tank full . Why? At subzero temperatures and sudden thaws, the metal from the inside, if the tank is half empty, fogs up. Then this frost melts and water gets into the gasoline.

Selection of electric generator

A home power plant consists of an internal combustion engine and a rotating generator that produces electricity. The most common are four-stroke models with a maximum speed of 3 thousand revolutions. The volume of the fuel tank in domestic models is 10-15 liters. The main selection criterion should be the area of use. Generators can act as the main source of energy, but more often they are a reserve in an emergency.

When choosing, you should pay attention to some parameters:

motor resource;
power;
efficiency;
convenience.

When connecting, it is important to ensure the coordinated operation of 3 elements:

home network - consumer;
centralized supply chain;
cable from the reserve.

Before connecting, determine the following points:

safe and economical location of the electric generator;
frequency of power failures in the general network, need for automation;
calculated power consumption taking into account reserve and losses.

A suitable connection diagram must be provided.

A continuous supply of energy is quite expensive; a private home rarely needs such provision. Important consumers of electricity, such as a computer, can be connected to an uninterruptible power supply.

First of all, it is necessary to calculate the power of energy consumed. It is the sum of the load capacities that are planned to be connected. Additionally, a margin of 30% of the total value is added. This is required to take into account the starting currents of motors of household appliances, which are 2-3 times higher than permissible. You can select a unit based on its estimated power.

Calculation example. The house has a washing machine 2 kW, refrigerator – 0.5 kW, electric stove – 3 kW, general lighting – 0.5 kW, TV and computer – 0.5 kW. The total power is 6.5 kW, but when taking into account the reserve, the calculated value will increase to 8.5 kW.

The connection diagram for a gasoline generator to the home network should be as simple as possible. The main thing is that it is correct and allows the unit to be provided with the required load.

About direct connection via socket

The fastest and easiest way to organize a constant supply of current. It is enough to purchase a special extension cord with plug connections, or make it yourself. Manufacturers do not recommend using such solutions, but many buyers prefer them due to their simplicity.

The method consists in the appearance of voltage in other sockets, if you organize a parallel connection of all consumers in the home network, and then apply “phase” or “zero” to one of the sockets.

This scheme also has disadvantages, although there are not very many of them:

It is impossible to track the moment when the standard electrical network began to work stably again, the restoration was completed.
It is necessary to use additional devices for protection.
The input machine is always turned off.
There is too much stress on the wire.

If a gasoline generator is connected directly through an outlet, then the supply of energy from external sources must be completely excluded. To do this, machines are turned off at the entrance. Otherwise, the neighbors will simply use the electric current, free of charge.

The increased load leads to the fact that gasoline units simply stall.

Note! If the home line is designed in accordance with all standards, an RCD is additionally used for protection. When connecting gas generators to the network, it is important not to reverse the polarity of the wires. Sometimes it is recommended to keep track of what is connected to which terminals.

The system will shut down if the connection is incorrect. Everything will have to be redone.

Automation

Necessary equipment

To technically correctly connect the generator to the home network, you do not need many devices. Here are just a few of the requirements that must be met:

Connecting the generator to the house

Providing separate input. It is recommended to choose copper wires with a cross-section of at least 4 mm2 for this purpose. They are laid starting from the input distribution device and ending with a specially equipped installation site.
Changeover switch. Recently, a large number of similar devices have appeared that can be used for personal needs. The main thing is to choose mounting on a 35 mm DIN rail; this is one of the most universal solutions. TDM-63 is an example of the cheapest brands. But there are better and more reliable devices - E200 from ABB, SFB from Hagger. Manufacturers themselves often write instructions describing how to connect the generator to the home network. .

Important! The switching and connection scheme for most devices is universal and simple. The common bus of outgoing loads is often connected to the lower part. Two separate inputs are connected on the reverse side, where the paired contacts are. The control key has three positions in general. The circuits are open when it is medium. Any manufacturers now allow the production of multi-pole devices. This makes it easier to work with three-phase networks, grounding or grounding systems of increased complexity.

A three-position or changeover switch has a main principle - a load switch. This leads to the fact that the design does not initially provide for a thermal or electromagnetic release. Each input requires additional protection using a machine. The maximum current for the latter is determined based on the permissible load along the supply line. It doesn't matter which bus the connection is made to.

A pair of two-pole circuit breakers can be used to independently manufacture the simplest version of changeover devices. You just need to follow a few simple steps:

Place the devices nearby.
One is turned upside down.
Then the keys are connected together, for which a steel pin is inserted into the standard hole. The rule is relevant for any type of electric current generator .

Connecting devices to the network