Comparison Briggs&Stratton 3750A vs Briggs&Stratton Pro Max 3500A

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 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.

Fuel consumption of a gasoline or diesel generator, and for combined models — when using gasoline (see "Fuel").

A more powerful engine inevitably means more fuel consumption; however, models with the same engine power may differ in this indicator. In such cases, it is worth considering that a model with a lower flow rate usually costs more, but this difference can quickly pay off, especially with regular use. In addition, knowing the fuel consumption and tank volume, you can determine how long one refueling will last; at the same time, in inverter models at partial load, the actual operating time may be noticeably higher than the theoretical one, see "Alternator" for details.

The time during which the generator is guaranteed to operate without interruption.

This parameter is indicated exclusively for liquid fuel models with a built-in tank, and according to the simplest formula: tank capacity divided by fuel consumption. However, in some models, data may be provided for a certain load level (which is specified in the notes); at a higher or lower load, the operating time will be shorter or longer, respectively. As for specific numbers, in most modern generators the operating time is up to 8 hours - this is quite enough for backup power and occasional use. More reputable models are capable of working for 8 – 12 hours, and an indicator of 13 hours and above is typical mainly for professional solutions.

We also note that, theoretically, many generators can be refueled without shutting down, but in practice it is better to take breaks and not exceed the stated time of continuous operation - this will avoid overheating and increased wear.

- 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.

The electric generator has wheels for moving from place to place. Most often, the design provides for a pair of wheels and a pair of parking supports: during working hours, the supports play the role of brakes, and when moving, they need to be raised above the ground and the generator rolled on two wheels; however, there are models on 4 wheels. Anyway, this feature greatly simplifies transportation: it is much easier to roll the unit than to carry it on weight. This is especially true in light of the fact that the weight of a modern generator can exceed 100 kg: several people will be needed to carry such a weight, while wheels often make it possible to manage by one person.

The total weight of the unit - as a rule, excluding fuel; The full fill weight can be easily determined by knowing the tank capacity.

In general, more powerful generators inevitably turn out to be heavier, but models with similar characteristics can differ noticeably in weight. When assessing these differences and generally choosing an option based on weight, it is worth taking into account the specific application of the generator. So, if the device will often be moved from place to place - for example, when used “on the road” - it may be worth paying attention to lighter units that are more convenient to transport. However, it is worth considering that the downside of a lightweight design is often an increased cost or a reduced degree of protection. But for stationary use, you can not pay much attention to this parameter - or even the opposite: choose a heavier (and, as a rule, more advanced and functional) option.

Regarding specific numbers, it is worth noting that modern generators in general are quite massive. So, a small weight for such equipment is considered not only up to 20 kg, but even 20 – 30 kg ; Many units weigh 150–200 kg, or even more, and the weight of stationary industrial models is already measured in tons.