Electricity comes from the socket. actually. But in an emergency, In the holiday house, Mobile generators do a good job in mobile homes or off-road. This is what you need to know before purchasing.
As with any upcoming purchase of equipment, the question arises when choosing the right generator: What is the machine supposed to do?? In this case, that is the question of consumers, to be operated with self-made electricity. Experts distinguish between resistive, inductive and capacitive loads.
consumer
Ohmic consumers, for example light bulbs, heaters and hotplates, convert the power consumed into light or heat. The specified power in watts is always the power, which the generator must supply.
Inductive consumers, such as power tools, mowing machine, kitchen appliances or water pumps, are devices, powered by an electric motor. Electric motors need the two to build up the electromagnetic field and to run up to the operating speed- up to six times the specified nominal power. The generator must therefore have sufficient reserves, to provide the high starting current. Synchronous generators can easily cope with a starting current, which is three times the rated power. Machines only, that start up under very high loads, such as water pumps or circular saws with particularly large saw blades, you therefore need a generator with a higher output. capacitive consumers, for example lightning systems, as used by professional photographers, need generators with special control.
If several electrical consumers are to be operated with the generator, must the generator power (in kVA) at least the sum of all connection values (kW) correspond to. For the leisure sector, generators with approx 1 kVA. If more powerful electric tools are also to be operated, recommend devices with 2 kVA or more.
Mobile power generators essentially consist of two components, the engine and a generator with control.
Motor
The engines are mostly four-stroke petrol engines, diesel engines are also used in larger models. A few devices can also be operated with gas. These are very suitable for weekend homes or mobile homes, who already need a larger supply of gas for cooking and heating anyway.
Look for a powerful and environmentally friendly motor with high efficiency. The total output of the generator depends very much on the efficiency of the engine (maximal 75 to 80 percent) and the generator off. A power generator with an engine power of 1 kW (1,36 PS) thus supplies at most electricity for consumers 650 W.
Modern OHV engines with overhead valves are characterized by low consumption and few pollutants. The best engines not only meet European regulations, but also the stricter requirements in California. Which of these regulations the device complies with, can usually be recognized by stickers or in the operating instructions.
Generator
The generator converts the kinetic energy generated by the engine into electrical energy. In principle, it works just like the generators in large power plants or the alternator in a car. By rotating magnets (Rotor) electrical voltage is induced in a coil (generated).
asynchronous generators. These comparatively inexpensive power generators are short-circuit proof and maintenance-free. On the other hand, however, they are very sensitive to high starting currents from electric motors. Therefore, they are actually only suitable for ohmic loads.
However, if asynchronous generators are to supply inductive loads with electricity, then you have to factor in a multiple of the rated power as a reserve for starting these devices.
synchronous generators. until
On the other hand, these power generators can be briefly overloaded with three times the specified nominal load. However, they are more complex in construction and require special regulation. That is why they are also significantly more expensive.
The big advantage is their better suitability for inductive loads, a more even output voltage, high synchronization properties and high efficiency. That is why most mobile power generators for private use today are equipped with synchronous generators.
regulation
In order to adapt the output voltage to the consumers connected, modern power generators are now electronically controlled. The electronic control ensures stable voltages and frequencies, which are primarily required for the operation of electronic devices.
A special feature is the inverter control, previously only available on Honda power generators. It not only ensures a perfect frequency- and voltage stability, but also for load-dependent engine management, saves gas, if full performance is not required.
degrees of protection
Depending on the area of application, generators should meet certain protection classes. IP 23 protects against the ingress of medium-sized foreign objects and spray water coming from above (up to an angle of 60°). Such devices should be used primarily in dry areas.
IP 44 protects against contact with objects, that are greater than 2,5 mm, and against splashing water from all directions.
IP 54 Protection against dust and splash water from all directions. These devices are recommended for occasional outdoor use, even when it gets wetter.
noise
When used in the leisure sector, the noise generated by the engine can be very annoying. The compact devices in particular therefore often have special noise insulation, which significantly reduces the noise level. When comparing the devices, pay attention to the guaranteed sound power level and consider, that changes with every increase around 3 dB(Category) doubled the volume.
Who wants to use a generator, to create light in the cottage and watch TV, should best put him in a separate, place in a soundproof room, Or just use it to charge batteries, which silently supply the lamps and the television with the necessary energy in the evening.
On the other hand, the power generator is used to operate power tools such as hedge trimmers, a circle- or use a chainsaw, the noise level is far less disturbing.
weight
If you are looking for a mobile power generator for on the go, Size and, above all, weight also play an important role.
devices up to about 25 kg can still be carried comfortably. For one 40 kg or even 50 kg heavy power generator you actually need your own chassis.