How to choose a generator - 10 questions and answers

Hello Sergey! Most generators are a 2-phase electric machine in the output socket of which there are 2 phases with an amplitude of 115 volts. Question: which of them must be earthed to get 220 volts? Almost ALL generators at the output have a so-called approximated sine wave, or meander, heating boiler pumps, refrigerator engines do not want to work with such electricity. The ringing is standing, it’s already laying ears. Question: what to do? How to make a relatively normal sine wave out of this miserable semblance of electricity. I do not think that you have not encountered such a problem with your experience.Sincerely, Valery.

ValeryI support! I myself have a problem with starting a grinder with speed control on the generator. Does not start!

Hello, Valery. Thanks for the question, quite relevant. Experience, thank God enough :) Yes, indeed, if you check with a probe, then any of the "holes" will glow. But what about what you checked the voltage? Regarding the case? Then where your generator “breaks” into the case, since the generator (alternator) coil is isolated. We connect the Zero city, provided that you do not "tear" it when connecting the generator to one of the poles, BUT, before that, you should definitely check if one of the terminals is grounded to the case, since it met generators in which one of the terminals was shorted to the case, that is, it turned out to be a dead-grounded neutral system, TN-C. If it so happens that you are "tearing" a city zero, then one of the conclusions is grounded, as a result, we get L-N in the socket.

Regarding the rumble of engines, yes, unfortunately, this is the case, especially for low-end models. In Normal Generators, this is not so noticeable.

The quality of voltage is particularly demanding modern boilers. If they refuse to work with the generators, we defeat them with an additional resonant filter, which smoothes out all kinds of “garbage” generated by the generator or the online UPS, the main thing is that it (the UPS) picks up the generator.

Viacheslav,
And what power do you have angle grinder and generator? If they are approximately the same in power, then the generator may not extend your grinder, given the large inrush currents of the grinder.

Angle grinder 750 W, 2.2 kW generator. If you connect a watt 150 lamp in addition to the angle grinder, then it starts.

The usual 750 W angle grinder (without speed control) starts normally.

The main issues have been addressed, but direct current gas generators with an inverter are common on the market, I ask you to highlight the topic of generators with a pure sine wave and a modified sine wave, what is the difference (principle of operation) and which generator is better to take for what purpose, how cheaper (generator with an inverter + smoothing filter or sinusoidal generator).

Viacheslav,
For angle grinders with soft starters. To understand why the generator does not pull easily, just remember Ohm's law :). How does a soft start in grinders work? Voltage is applied to the motor gradually. Now we substitute the values, knowing the power of your grinder. I = P / U / For example, when you press a button on the engine, a voltage of 100V begins to flow, the engine power is 750 watts. 750/100 = 7.5 A, and this is approximately 1.6-1.7 kW ...

When choosing a generator, there are several points that must be considered. One of the conditions is the generator power, nominal and maximum. The next question is the type of fuel for the generator - gasoline, diesel, liquefied or natural gas. Another factor is the operating time from one tank of fuel. You should also choose the type of start of the electric generator - manual, from the lace or the generator can be started by an electric starter. It is also worth deciding on the type of load transfer from the network to the generator and vice versa. Will this happen automatically or will it need to be switched manually using a special load switch.

Generators are available in various output capacities - from a small portable 800 W unit in the form of a small suitcase, to huge units that can provide electricity to a hospital, school and other institutions during a power outage (1000 kW or more).

A small portable 800-1000W generator can light eight to ten 100-watt light bulbs or provide energy equivalent to these light bulbs.

The most popular generator is from 3,000 to 5,000 watts (3 to 5 kW). Generators of such power are able to provide power to the most necessary appliances in our house. When the generator is working, you should refuse to use an air conditioner, heater or electric stove, as they are too powerful for our 5 kW gasoline generator. From a generator of this power, we can use lighting, a refrigerator and a freezer, a microwave and a small pump for water. When using a generator, try to reduce energy consumption to a minimum, turn off the lights and equipment when they are not needed. If the maximum permissible load is exceeded, in the best case, the protection on the generator will work, in the worst case, the generator will fail. When the generator is operating at maximum permissible power, in addition to increased fuel consumption, increased wear of the unit itself occurs.

In order to determine how powerful a generator you need, you need to add up all the power of electrical appliances that you are going to turn on at the same time. Also, when calculating, it should be noted that not all devices can work simultaneously. An example is a pump or a refrigerator, which are turned on as needed.

In addition to the devices that you intend to use, there are many devices that everyone forgets about: watches, devices with power supplies such as modern televisions with remotes that use a small amount of energy, even when they are supposedly in sleep mode To determine how much power (power) using the device, check the label on the device itself or the instruction manual.

Sergei.,

There is something else, it seems to me. If the generator did not draw in power (and I have 2.2 kW), then the ATS would be turned off. And here the angle grinder is trying to start and stops, or turns at low speeds. The situation changes if you connect an additional 700-1000 watts of load to the generator, then the angle grinder with speed control starts and works as it should. Disable add. load and the angle grinder stops. Other tools also work, such as a grass trimmer.

According to the last comment. The problem is most likely in the voltage regulator. If AVR is installed, then it does not have time to apply voltage to the armature, as a result of which excitation does not occur, if the unit is standing, it is worth looking at the capacitance, in what condition it is or whether it corresponds to the required rating. You stupidly does not start excitement with a heavy load.