Comparison Kemage KM2500i vs Konner&Sohnen KS 3100iG S

The type of fuel that the generator's engine runs on.

— Gasoline. One of the main types of fuel for internal combustion engines. Gasoline generators are usually cheaper than diesel generators, all other things being equal, but they are more expensive to run due to the higher price of gasoline; in addition, they usually have a shorter resource than diesel ones. Therefore, it is believed that gasoline generators are well suited primarily as a backup power source in case of a power outage.

— Diesel. Diesel generators are usually more expensive than their gasoline counterparts; on the other hand, diesel fuel is cheaper than gasoline, so the increased cost may well pay off with regular use. In addition, diesel generators have a longer resource and a larger power range than gasoline ones. This allows them to be used as both backup and main power sources, including at rather "energy-intensive" objects.

— Gas. The advantages of gas-fired generators are relatively low noise levels and low emissions. On the other hand, the use of gas as a fuel is associated with certain difficulties: it is necessary to connect to a gas pipeline or regularly replace special cylinders, the fuel system is especially sensitive to leaks, etc. Therefore, there are relatively few such models produced, and most of them are stationary high power generators, in which the mentioned disa...dvantages are covered by the advantages.

- Gasoline / gas. Models capable of using both types of fuel indicated. This gives the user the opportunity to choose the option that best suits a particular situation, and also reduces the likelihood of being left without fuel at the most inopportune moment; on the other hand, such models are more expensive than single-fuel ones. The technical features of gasoline and gas are described in detail above.

The rated power of the generator is the highest power supply that the unit is capable of delivering without problems for an unlimited time. In the “weakest” models this figure is less than 1 kW, in the most powerful – 50 – 100 kW or even more ; and generators with welding capabilities (see below) typically have power ratings ranging from 1 – 2 kW to 8 – 10 kW.

The main rule of choice in this case is this: the rated power must not be lower than the total power consumption of the entire connected load. Otherwise, the generator simply will not be able to produce a sufficient amount of energy, or it will work with overloads. However, to determine the minimum required generator power, it is not enough to simply add up the number of watts indicated in the characteristics of each connected device - the calculation method is somewhat more complicated. Firstly, you need to take into account that only the active power of various equipment is usually indicated in watts; In addition, many AC electrical appliances consume reactive power (the "waste" power consumed by coils and capacitors when operating at that power). And the actual load on the generator depends precisely on the total power (active plus reactive), indicated in volt-amperes. There are special coefficients and formulas for its calculation.

...The second nuance is related to the power supply of devices in which the starting power (and, accordingly, the power consumption at the moment of switching on) is significantly higher than the rated one - these are mainly devices with electric motors such as vacuum cleaners, refrigerators, air conditioners, power tools, etc. You can determine the starting power by multiplying the standard power by the so-called starting coefficient. For one type of equipment it is more or less the same - for example, 1.2 - 1.3 for most power tools, 2 for a microwave, 3.5 for an air conditioner, etc.; More detailed data is available in special sources. Starting characteristics of the load are necessary, first of all, to assess the required maximum power of the generator (see below) - however, this power is not always given in the characteristics; often the manufacturer indicates only the rated power of the unit. In such cases, when calculating for equipment with a starting coefficient of more than 1, it is worth using the starting power, and not the rated power.

Also note that if there are several outlets, the specific division of the total power among them may be different. This point should be clarified separately - in particular, for specific types of sockets (for more details, see “230 V sockets”, “400 V sockets”).

The maximum power supply that the generator can provide.

This power is slightly higher than the rated power (see above), but the maximum performance mode can only be maintained for a very short time - otherwise overload occurs. Therefore, the practical meaning of this characteristic is mainly to describe the efficiency of the generator when operating with increased starting currents.

Let us remind you that some types of electrical appliances at the moment of startup consume many times more power (and, accordingly, power) than in normal mode; this is typical mainly for devices with electric motors, such as power tools, refrigerators, etc. However, increased power for such equipment is needed only for a short time; normal operation is restored in just a few seconds. And you can evaluate the starting characteristics by multiplying the rated power by the so-called starting coefficient. For one type of equipment it is more or less the same (1.2 - 1.3 for most power tools, 2 for a microwave, 3.5 for an air conditioner, etc.); More detailed data is available in special sources.

Ideally, the maximum power of the generator should be no lower than the total peak power of the connected load - that is, the starting power of equipment with a starting factor above 1 plus the rated power of all other equipment. This will minimize the likelihood of overloads.

Model name of the engine installed in the generator. Knowing this name, you can, if necessary, find detailed data on the engine and clarify how it meets your requirements. In addition, model data may be needed for some specific tasks, including maintenance and repair.

Note that modern generators are often equipped with branded engines from famous manufacturers: Honda, John Deere, Mitsubishi, Volvo, etc. Such engines are more expensive than similar units from little-known brands, but this is offset by higher quality and/or solid warranty conditions , and in many cases, the ease of finding spare parts and additional documentation (such as manuals for special maintenance and minor repairs).

The working volume of the engine in a gasoline or diesel generator (see "Fuel"). Theoretically, more volume usually means more power, but in fact, everything is not so clear. Firstly, the specific power strongly depends on the type of fuel, and in gasoline units, also on the type of internal combustion engine (see above). Secondly, similar engines of the same power can have different volumes, and there is a practical point here: with the same power, a larger engine consumes more fuel, but by itself it can cost less.

The operating power of the engine installed in the generator. Traditionally stated in horsepower; 1 HP approximately equal to 735 watts.

First of all, the rated power of the generator directly depends on this indicator (see above): in principle, it cannot be higher than the engine power, moreover, part of the engine power is spent on heat, friction and other losses. And the smaller the difference between these capacities, the higher the efficiency of the generator and the more economical it is. However high efficiency affects the cost, but this difference can pay off with regular use due to fuel savings.

A pointer that allows you to monitor the remaining fuel in the generator tank. The simplest such indicators work only with a critical decrease in the level of fuel, warning of the need for refueling; more advanced ones constantly display the remainder. However, anyway, this feature makes it easier to keep track of the fuel supply and reduces the risk of a generator shutdown due to a forgotten refueling.

- DC output (DC 12 V). The presence in the generator of an output with direct power and a voltage of 12 V. The main function of this output is to charge car batteries, as well as power devices originally intended for cars (remember, 12 V is the standard voltage of on-board networks in passenger cars).

- USB port for charging. The generator has a USB connector (one or more) for charging various devices. Most modern smartphones and tablets can be charged from USB; this charging method is also found in many other equipment - from cameras and flashlights to electric screwdrivers and radio-controlled models. The standard supply voltage through this connector is 5 V, but the power may vary and should be specified separately.

- Synchronization with a smartphone. Synchronization with a smartphone allows you to control the operation of the generator remotely. Thanks to this, the user does not need to approach the device to, for example, start or stop it. Additionally, synchronization with a smartphone allows you to monitor the parameters of the generated electric power remotely and in real time. On the other hand, this will require a constant connection to the Internet and specialized software that must be installed on your smartphone.

- Autorun (ATS). A function that allows the generator to turn on automatically under...certain conditions, without user action. Autostart is used mainly when using a generator as a backup power source: while the main power is on, the unit is turned off, and if the mains voltage disappears, the ATS starts the engine, and power to the load begins to flow from the generator. Note that the presence of autostart is indicated only if the generator is initially equipped with an ATS electronic unit; models with the ability to connect such a unit are placed in a separate category (see below).

- Connector for the ATS block. A connector that allows you to connect an external autorun unit (ATS) to the generator; The block itself is not included. See above for more details on autorun; We note here that for some users this function is not initially needed, but it may be needed in the future - for example, if the generator is initially used in the construction of a house, and then it is planned to be installed in the same house as a backup power source. In such situations, this configuration option will be optimal: when purchasing the generator itself, you will not have to overpay for the ATS unit, and later, if necessary, you can buy and connect such a unit separately.

- Automatic voltage regulator (AVR). An automatic regulator that allows you to maintain a constant voltage level at the generator output. Such a regulator smoothes out differences arising from changes in engine rotation speed; This is especially important when connecting devices that are sensitive to power stability. It is worth noting that the presence of AVR is practically mandatory for synchronous generators (see “Alternator”), but in other varieties this function is not found: in asynchronous and duplex units it is not applicable in principle, and in inverter units the role of the regulator is played by the inverter itself, and they do not require additional electronics.

— Display. Own display mounted on the generator body. As a rule, this is a simple LCD screen that can only display numbers and some special characters. However, even such a screen can display various useful information: voltage, frequency, hour meter data, low fuel level warning, failure messages with error codes, etc. Thanks to this, control becomes more convenient and visual.

- Hour meter. A device that counts the total time that the electric generator engine has worked since it was first turned on. This helps to determine the general wear and tear of the engine and the need for its repair/replacement, which can be useful both when using the device for a long time, and, for example, to assess the quality of the product when purchasing a used electric generator. It is usually impossible to reset the hour meter without serious intervention in the design of the device.

— Voltmeter. A device that displays the power voltage output by the generator. The voltmeter can be made in the form of a separate dial scale, or its readings can be displayed on the generator’s own display (see above). In any case, this function allows you to carefully control the operating mode of the unit and reduces the risk that unacceptable voltage will be applied to the load.

- Parallel connection. The presence in the design of the generator of special connectors through which two or more units can be connected to a single electrical network (usually with the help of an additional device). This type of connection is used when one unit is not able to pull the entire load and the connection power exceeds the capabilities of the device itself. Also, a similar scheme has found popularity if one of the units is planned to be used as a backup power source.

- Remote start. Presence in a set of delivery of the generator of the remote control. It is made in the form of a wireless key fob and allows you to turn on/off the device from a distance without going near it.

Sound pressure level in decibels at a distance of 7 m between the noise source and the ear of the equipment operator. Since people do not work in the immediate vicinity of the generator, the parameter will be useful for estimating the noise level at a distance. For example, current European Union regulations require that the sound power of generating sets with a power of more than 2 kW does not exceed 97 dB — at a distance of 7 m, the noise from the generator engine will correspond to a sound pressure of about 72 dB.