The statistics are stubborn and undeniable figures, and they show that the sales of 12000 running watt generator are constantly growing, and not somehow, but exponentially. Those who studied well at school understand what is at stake: in 2014, generators were sold twice as much as in 2013. In 2015, it was twice as much as in the previous one. And according to the interim results of this year, generators have already become an indisputable hit of sales and covered the volumes of the last year by half, and after all, almost half a year ahead, and the peak of sales of mini-power plants falls precisely in the autumn-winter period.

The media are shouting with might and main that the growth in generator sales means that Ukrainians are very frightened by the power outages and are afraid of a gas cut. Boilers are purchased to heat water, and electric heaters are purchased to heat houses. That is, even more electricity is needed, and the coal supply at Ukrainian thermal power plants seems to be at zero, and all nuclear power plants are undergoing repair and maintenance. In general, oh, how hard it is, The only right way out is to buy a generator. Or diesel if you need a long-term trouble-free operation.

Everything is correct. The only thing we disagree with is that the smart and practical Ukrainian buyer, that is, you, is driven by fear. Buying a generator for a backup supply or for a constant supply of electricity is not fear, but a serious and thoughtful decision of a sober-minded person. After all, a power outage even for a couple of hours forces the owners to postpone household chores, it is impossible to cook food in houses with an electric stove, children are forced to prepare school lessons by candlelight or another weak additional lighting. In general, all home comfort is spoiled. If electricity is lost at the enterprise, in the working office premises, then the situation is even worse. Production stops, all computer operations are interrupted, and this is all a waste of a lot of money and the disruption of important transactions.

When buying, the question often arises: How to choose a generator of the required power and with the necessary functionality? Choosing a generator is a tricky science. But this, nevertheless, is not a Chinese literacy, and everyone who understands why he needs a unit can master a few simple rules when choosing a backup power plant. We have selected the most important ones for you.

## LET’S START BY CALCULATING THE TOTAL POWER OF ELECTRIC APPLIANCES

If we put aside brands and various functions, it turns out that the price directly depends on its power. The more powerful, the more expensive. But never be guided by the price, it is better to start the selection by calculating the required power. If you save money and choose with less power, then it may simply not be enough. And the electrical appliances either simply will not turn on, or overload will occur and it will begin to “twitch” and “choke”, or even completely fail. This is one mistake, and the second is choosing a very powerful generator. In this case, part of the capacity is not used, the fuel is burned, and a lot of money is wasted. Therefore, first, we begin to calculate the required power. For this:

- We list on a piece of paper all electrical appliances in the house, opposite each write its power in watts. The power of each electrical device is indicated on the tag or in the device’s passport.
- We divide all electrical appliances into vital and those that can be temporarily dispensed with. The most necessary ones are lighting, a refrigerator, an electric stove, in winter – heaters, a starting block for a gas boiler. … A water pump, a boiler, a computer are also very important for the comfort in the house. But vacuuming, ironing, and washing from the generator, it already borders on luxury.

**Vital****Secondary****Low priority**

- We select for ourselves all electrical equipment that will work constantly and simultaneously. The sum of its capacities is the power you really need. Also, highlight interchangeable electrical appliances, that is: you can turn off the computer and watch TV, or iron or wash without turning on the lights or the electric stove. Add all this up as well. But this is only a rough estimate.
- What is the inrush current ratio? An important nuance when choosing a generator is the starting current ratio. It is often indicated by the manufacturer directly on the device or in the datasheet and denoted cos φ (“cosine phi”). Its essence is that a little more power is needed to start the device than to operate it. Therefore, the power of each selected unit of electrical equipment must be multiplied by this coefficient. The result will be a larger number. But this does not apply to all electrical appliances. If the device needs current only to heat it, then its cos φ is equal to 1 or slightly more. It is not important when calculating power. This technique includes light bulbs, heaters, irons, boilers, kettles, electric stoves. But if the electrician performs other functions (makes something spin, move, or starts complex circuits), then the “cosine phi” can be 2 or 3. In a welding machine, for example, 4. Such a factor must necessarily be multiplied by the power of the device in order to obtain the number of the required starting power. For example, a vacuum cleaner has a starting current ratio of 1.5. If the power of the vacuum cleaner is 2 kW, then to start it needs: 1.5×2 = 3 kW. If you “left” 2 kW of power for the vacuum cleaner, then it simply will not turn on, because it needs 3 kW to start.

Don’t forget about the power reserve. For normal operation of the generator, without overloading, it is necessary to create more “power in reserve”. To do this, add 20% to the total capacity. Such stock will save you from breakdowns and will be salutary even when you buy some new electrical equipment. For stationary power plants, it is better to add as much as 30%, because their work will not be interrupted.