Our fellow citizens often go to summer cottages, which allows them to have a good rest and gain strength in the fresh air before a new working week. With all the advantages of such a weekend, the dacha usually has one unpleasant feature: unreliable electrical networks, which, for various reasons, are prone to failures. Of course, you can solve the problem of loss of electricity with a portable gas generator, but it is quite bulky, heavy and expensive.
In such a situation, it is advisable to look for an alternative energy source, the functions of which may well be taken over by an automobile engine. Of course, the designer of a passenger car does not provide for its use as a drive for an electric generator and does not install a power take-off on it. Therefore, we have to go a different way.
Car inverter and connection options
The 220 V AC source is not connected to the engine, but to the car battery. The source is built according to the inverter circuit and converts the constant voltage of the vehicle on-board network into an alternating 220-volt one. The conversion takes place due to the fact that the internal generator of the inverter is supplied with constant voltage, from the output of which the 50-Hz alternating mains voltage of 220 V is removed.
Car inverters fall into two main groups. Devices of the first group, Figure 2, are connected directly to the battery, the second, less powerful type of cabin-type units is designed to work through a cigarette lighter.
Limiting the power of the car inverter
Regardless of the connection option, the power supply circuit of the inverter in the complex forms a sequential structure, the maximum output power of which is limited by the lowest-power unit in its composition. For clarity, in the diagrams of Figures 2 and 3, it is marked with a red check mark.
For the scheme in Figure 2, the weak link is a generator, the power of which, even for most trucks with a carrying capacity of up to 10 tons, does not exceed two or three horsepower, and in cars it is usually a maximum of 1 - 1.5 hp. The choice of just such a power value is due to the fact that the generator in the peak load mode must charge the car battery and ensure the normal operation of the remaining on-board consumers: high beam lamps, heaters and similar to them.
Taking into account that the inverter as an additional consumer does not have to overload the generator, its maximum power is 1000 W. This is evidenced by a selection of data on car inverters designed for direct connection to the battery terminals and included in the top 10 of the Yandex issue:
- Api-400-03 - 500W
- ENERGY AUTO LINE 120 - 1000 W
- TELEFUNKEN TF-PI02 - 600 W
If the inverter is powered from a car cigarette lighter according to the diagram in Figure 3, then the power is additionally reduced by two to three times.
Main consumers
The list of the main consumers of electricity generated by the inverter is determined by their power and requirements for the quality indicators of the current taken from the output of the device. The latter is set by the principle of operation of the inverter, which, due to internal circuitry limitations, generates the so-called. approximated sinusoid, Figure 4. It has a shape that roughly reproduces a "pure" sinusoid.
The list of consumers that can be connected to a car inverter includes, but is not limited to, such common devices as:
- chargers for tablet and laptop;
- TV set;
- most LED fixtures;
- low-power drill.
A refrigerator, iron, and electric kettle will likely blow the inverter fuse when attempting to connect.
Thus, a car inverter can be considered as an effective temporary hut, but with frequent network failures and constant stay in the country, it would be better to get a full gas generator.