Despite the developed modern electrical networks, even today power outages - Not unusual. Rural and country houses and dachas especially suffer from these problems. An excellent way out of this situation can be to use a gasoline or any other generator as a backup source, but for this it is important to know the generator connection diagram.
Content
- Varieties of connection schemes
- What is Rocker Switch
- Semi-automatic connection of a backup source
- Auto switch with auto start
Varieties of connection schemes
Existing schemes of varying complexityavailable for use in private homes and apartments can be divided into three categories:
- Manual switching.
- Semi-automatic connection.
- Automatic connection with auto start.
Depending on your capabilities and tasks, you can choose any of them. But before considering specific schemes for connecting a generator to a house network, it is necessary to determine the general rules for switching backup sources, regardless of the switching method used:
- Efficiency. The connection of a backup source should be provided with a minimum of simple and unambiguous switching, which can be done even in the absence of lighting.
- Safety for humans. All switches must be completely safe for the operator - switches and switches must be used of a closed type and placed at face level. This ensures electrical safety and excludes injuries.
- Safety for equipment. The circuit must reliably protect the equipment of the house and substation from abnormal situations - the wrong sequence switching, sudden appearance or disappearance of the main or backup power supply, short circuit, overload and etc.
- Visibility and simplicity. If the switching system is not fully automatic, then it should be as clear and simple as possible. This will not only eliminate operator errors, who are most likely to be a layman, but also make the circuit more reliable and maintainable.
In order to power the house from a backup source, it is necessary, first of all, to disconnect it from the main one. Moreover, this must be done so that both sources do not turn out to be connected in parallel. Otherwise, when the main supply voltage appears, an accident will occur caused by the supply of the opposite voltage.
In other words, the main network and the generator will “fight”. To exclude such situations, the so-called rocker switches or rocker switches must be used without fail.
What is Rocker Switch
Unlike a conventional switch, this device allows you not only to turn on or off, but to switch the circuit.
Switch working principle
Both designs use a switch. In the first case (picture on the left) you can light one of the lamps with one click, in the second - connect the lamp to any power source. Please note: in neither case, the switching contacts of the breaker are closed with each other. This is the main property of the rocker switch (knife switch).
Rocker switch (left) and switches
As you can see from the photo, the switch differs from the switches only in design, but the principle of operation is the same for them. How will the diagram of connecting the generator to the network at home using a circuit breaker look like? For this you will need double pole switch and nothing more.
How to connect the generator to the network at home (diagram)
One turn of the AB knob, and the consumer (house or apartment) switches to power supply from the backup source, while simultaneously disconnecting from the main one. The last point is very important - if voltage appears in the main network, it will not "meet" the generator voltage in any way. If your house uses a three-phase network, then the connection diagram of the electric generator will differ from the one given only by the number of poles of the changeover switch.
Semi-automatic connection of a backup source
Since the need to switch to a backup source arises under quite certain conditions (loss of the main power supply), organize automatic switching of sources at all not difficult. To do this, it is enough to use electromagnetic switch or a relay of appropriate power. As an example, we can take the REK77 / 3, which has three switching groups and withstands current up to 10 A (2.2 kW).
Electromagnetic relay REK77 / 3
The diagram for connecting an electric generator using such a relay will look like this.
Semi-automatic network switching scheme
As you can see from the diagram, the relay coil is connected to the main power source - the network. In the presence of mains voltage, the relay is activated and power is supplied to the load. As soon as there is a loss of voltage, the relay will release and switch the load to power from the generator (the figure shows just such a state). When the standard power supply is resumed, the circuit will return to its original position - the standard one.
The only, but serious drawback of such a scheme is the absence of an autostart of the generator, which plays the role of a backup source. That is why this design is called semi-automatic - the switch has occurred, but the generator will have to be started manually. But if you have generator with electric starter, then this problem can be partially solved by using a free relay group.
How to connect a gas generator to the network at home (circuit with autostart)
Now, if the main voltage is lost, relay K1 will not only switch the load, but also supply 12 V to the generator starter and timer, which will periodically start the gas generator. As soon as the generator is started (voltage appears at its output terminals), relay K2 will work and turn off the autostart system. Of course, this scheme is extremely simple and has a lot of disadvantages. Firstly, it will not drown the generator when switching back. Secondly, if the generator does not start for one reason or another (cold, poor start control, etc.), then the system will simply drain the battery, eliminating the possibility of starting the generator at all.
Auto switch with auto start
From all of the above, it can be seen that it is impossible to completely automate the process of switching a house from the network to the generator using simple methods using two or three parts. But it is too early to give up, since such systems not only exist, but are also quite affordable. Their name is ATS - Automatic Reserve Entry. Such units can be supplied as a complete set with gas generators, or 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 mains in case of power failure.
- Gas generator start with alarm signaling of failed start.
- Switching to power from the generator only when it enters operating mode.
- Monitoring and automatic regulation of voltage and frequency depending on the load.
- Overload and short circuit protection.
- Calculating engine hours.
- Switching to the main source when renewing energy supply.
- Stopping the generator.
- Recharging the starter battery.
As you can see, the list of functions performed by the AVR is quite wide, but structurally, alas, it is very complicated. Today, almost all such devices include microcontrollers and only a specialist with the appropriate knowledge and experience can assemble the ATS with his own hands. That is why the independent production of a full-fledged autorun system will not be considered in this article.
Is it difficult to independently connect a generator with ATS to the house network? Not at all. The device comes with detailed installation instructions with all the diagrams that any electrician can easily understand. The general structural diagram of connecting the automatic system to the house network will look like this.
General structural diagram of connecting the generator to the network of a country house
