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Brushed vs Brushless DC Motors

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Brushed DC Motors

Brushed DC Motors consist of a motor and a controller, which permanently supplies the motor with direct current. Inside the DC motor, the so-called armature plate, a magnetic field is generated via windings. Due to the magnetic field of the housing magnet, the armature starts to rotate by attraction and repulsion between both magnetic fields.

This rotation continues until two pairs of magnets with the same polarity face each other. Now the polarity of the current is reversed in the armature winding via brushes, which serve as current supply, and the collector, which serves as a mechanical switch. This allows the armature to continue rotating by attracting and repelling the newly polarized magnetic fields.

During this process a lot of heat and sparks are generated by friction, which leads to wear and tear of the collector and brushes and finally to motor wear and tear. This in turn can cause the motor to overheat very quickly and lose power and torque.

Brushed DC motor have several advantages. For example, multi-motor systems require only one controller and switching effects run very smoothly.

Due to the simple construction of the motor, it is very cheap to buy and can be easily repaired and maintained.

Because of the friction of the brushes inside the motor, the motor also gives a very good sound. Due to the massive construction the higher weight often contributes to the optimal center of gravity of the RC.

Due to the constant friction of the DC motor brushes and the wear of the carbon brushes inside the motor, the brushed motors have a limited life span and speed, and have a lower performance level than brushless motors. The wear and tear of the motor must be counteracted by regular maintenance.

 Replacing old, worn collector carbons is very important. Short old carbons must be replaced immediately, as they can easily jam in the guide and in the worst case damage the collector. Cleaning the collector increases the conductivity and thus also the motor power. The heat development can also be reduced. Furthermore, it should be noted that driving in the wet will wear out the motor even faster and should be checked after every rain ride.

brushed motorsdc motor

Brushless DC Motors

Brushless DC motors do not have carbon brushes which change the poles in the motor, but have a controller which takes over this task.

In a 3-pole motor, the controller generates a so-called rotating field by switching a DC voltage to two of three motor coils, whereby the third motor coil serves as a sensor line and determines the respective position of the rotating permanent magnet. Due to the magnetic field of the permanent magnet and the magnetic field of the motor coils, the permanent magnet begins to rotate by attraction and repulsion of the magnetic fields. This rotation continues until two pairs of magnets with the same polarity are almost opposite each other. Now the controller changes the voltage on the motor coils and the process starts all over again.

brushless dc motor

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dc motor

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In addition, brushless motors are differentiated between internal and external rotor DC motors:

  • With internal rotor DC motors the inner part, the permanent magnet, of the motor rotates and the outer shell, the motor housing, is fixed. With internal rotor motors, the motor coils are mounted in the fixed motor housing. The permanent magnet is attached to the rotating rotor, which is also connected to the drive shaft. Due to this design, internal rotors achieve a higher speed, but have less torque than external rotor models.
  • With external rotor models, the motor housing rotates and the inner part of the motor is fixed. Here the permanent magnets are attached to the rotating motor housing. The drive shaft is thus connected to the outer housing (motor bell) and rotates with it. Inside the motor, the so-called stator, the motor coils are attached around which the motor bell rotates.

Brushless DC motors have a rather lower heat development, because they do not have carbon bristles inside the motor and therefore no frictional energy is generated. Nevertheless, it is recommended to install a motor cooler, as the motor housing of brushless DC motors gets warm.

Most brushless DC motors also have a very high efficiency in terms of battery life and performance.

The maintenance requirements for brushless motors are minimal. The only thing to be considered is that when you buy the motor it is well sealed against water and dirt and the rotor is properly spaced in the housing. The ball bearings should be re-oiled regularly and checked for stones and sand.

Conclusion:

An engine that is in good shape and works flawlessly is a pleasure. Maintenance and care are essential for every DC model. For beginners and hobby riders, an inexpensive brushed motor is certainly a good option. For advanced model builder, the more expensive brushless motors offer a good possibility to equip their RC model due to better performance, higher speeds, easier maintenance, and longer life.

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Alternators | Alternator Parts

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Alternator Definition: the electrical generator in a vehicle

The power grid in a vehicle with an internal combustion engine, for example a car or truck, is usually fed by a generator, which is often driven by the engine via a belt. Since the operation of the headlights (i.e. the generation of light for lighting purposes) was originally the most important task of generating electricity on board, the term alternator has become commonplace for the generator. In the meantime, almost every car contains a large number of other electrical consumers, which together require considerably more electrical energy than the headlights.

alternator

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Other names for the alternator are generator and power generator.

Since on the one hand the engine speed and on the other hand the electrical load is variable, a rechargeable battery is generally used as an energy storage device. The same battery serves as a starter battery, i.e. for starting the combustion engine, and for supplying consumers when the combustion engine is switched off. The alternator contains a charge regulator, which enables the battery to be charged properly (with adequate current and avoiding overcharging). It also limits the electrical voltage at high engine speeds to prevent damage to loads.

The regular operating voltage of the vehicle electrical system is quite low in a car: usually about 12 to 14 V, in trucks about twice that. Since the power output in a car can already be several kilowatts, quite high currents are required – sometimes over 200 A. Therefore, the alternator must be connected by quite strong cables, and the contact points must be clean.

If an alternator is defective, this is usually indicated in the car by the charging indicator light continuing to shine even when the engine is running.

Direct current and three-phase alternators

Old alternators, as used until the 1970s, were mostly electrically excited direct current generators. At low engine speeds, at least when idling, the electrical voltage generated was often too low to supply consumers or charge the battery. Nowadays, three-phase generators are almost exclusively used in conjunction with a rectifier, which can deliver considerable power even at low engine speeds. (The transmission ratio for driving a generator is often selected so that the full power can already be delivered at idle speed and two thirds of the full power – which unfortunately means reduced energy efficiency at high engine speeds).

Increasing power demand in vehicles

The alternators of today’s cars are designed for a maximum output of sometimes more than 5 kW, sometimes even for about twice that. In the future, the electrical power requirement is likely to rise even further, since not only are more and more comfort functions being demanded, but also various functions important for the engine itself are increasingly electrified. For example, radiator fans, cooling water pumps, power steering and in some cases even compressors of air conditioning systems are increasingly being operated electrically.

Despite the energy losses in the alternator and electric motors, this can be energetically advantageous, because it enables operation that is better suited to the respective requirements. For example, it is very annoying in car air-conditioning systems that a compressor driven directly by the engine withdraws a certain amount of power from the engine even when the air-conditioning system is not running at all.

Modern starter alternators can replace the alternator and the starter (starter motor); they allow higher power to be produced with greater efficiency than traditional alternators.

As the power output increases, a low on-board voltage of 12 V becomes a limiting factor, because very high electrical currents (e.g. 200 A for a power output of 2.4 kW) occur, and this requires thick and heavy cables. For this reason, significantly higher on-board voltages are likely to be used in the future, and naturally also alternators with a correspondingly higher nominal voltage.

alternator

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Energy efficiency of alternators

The alternator is driven by the combustion engine and brakes it in the process; it therefore absorbs mechanical energy in order to be able to deliver electrical energy. The mechanical power absorbed can be significantly higher than the power output, since considerable energy losses also occur, especially at high engine speeds – for example, due to friction, for driving the fan (fan wheel) that cools the alternator, and due to ohmic losses in the coil windings and in the rectifier. Even without electrical load, the drive of the alternator requires a certain driving power, which then increases accordingly with electrical load (as a result of magnetic forces).

In old cars, the energy efficiency of the alternator was usually quite low; however, only relatively low power was converted anyway. The efficiency could easily be well below 50 %. More efficient devices would have been possible, but were probably not realized due to cost pressure. In modern vehicles, much higher electrical power is needed to supply a large number of consumers; several kilowatts may be required (see above).

Here, the efficiency of the generator becomes more important in order to keep fuel consumption low and also to prevent the cooling effort for the generator from becoming too high: The power lost there becomes heat, which must be safely dissipated to avoid destruction. Unfortunately, the problem with today’s alternators is that high efficiency for a wide range of speeds and loads is difficult to achieve.

Especially the operation at high speed but low load is quite inefficient. Therefore, even a peak efficiency of e.g. 80%, which some modern alternators can achieve, will probably result in an average practical efficiency of only between 50 and 70%. Modern starter generators in combination with suitable power electronics could be even better.

alternator

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Recuperation with alternators

To a very limited extent, alternators can also be used for recuperation, i.e. for the recovery of braking energy in micro-hybrid vehicles. For this, it must be possible to increase the power generated during braking in a targeted manner, and the additional power is fed into the vehicle battery. (At other times, less power can then be generated, so that the engine is less loaded and fuel is saved). The recoverable power can be limited by the alternator or by the battery, usually to a few kilowatts.

In vehicles with a true hybrid drive, both units are much stronger, so that higher braking power can be used; in this case, we no longer speak of an alternator, but of a generator, or possibly a powerful electric machine that can be used as an engine or generator. For the transport of corresponding power, considerably higher electrical voltages are then required (several hundred volts), which is why the normal on-board power supply cannot be used for this purpose.

It is also possible to reduce the power output of an alternator for a short time if there is a high demand for drive power (e.g. when accelerating). In this way, acceleration in particular can be slightly improved without increasing the engine power, and with minimal technical effort.

6 Best Power Efficiency Guide For Generator

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Definition: a machine for generating electrical energy from mechanical energy

More specific terms: synchronous generator, asynchronous generator, linear generator, external pole generator, internal pole generator, direct current generator, alternating current generator, three-phase generator

An (electrical) generator is a machine that can produce electrical energy from mechanical energy. By design, most generators strongly resemble certain electric motors, and many electric machines can indeed be used as motors or generators.

The term generator is often used in a broader sense than a technical device that converts mechanical, chemical, thermal or electromagnetic energy directly into electrical energy. For example, a thermoelectric generator can produce electrical energy directly from heat. Photovoltaic cells are also generators in this sense. However, the rest of this article applies to electromechanical generators.

Power Efficiency is the ratio of useful power output divided by the power input (total electrical power used).

Power efficiency principle and designs

The basic physical principle of the generator is electrical induction: a voltage is induced in an electrically conductive coil when the magnetic flux through the coil changes. This is achieved by moving a magnet against the coils. There are two different ways of doing this (apart from the less common principle of the linear generator), both of which are frequently used:

  • With the out-of-pole generator, the magnetic field is generated in the stator (the non-moving part of the generator), and electrical energy is generated by induction in the rotor. It must then be transferred to the outside, e.g. via sliding contacts with brushes, which is problematic at high power levels.

  • With the internal pole generator, the magnetic field is generated in the rotor, and induction takes place in the stator. In the case of electrical excitation (see below), electrical energy often has to be transmitted via brushes again, but to a much lesser extent, as the energy required for excitation is only a small fraction of the generator output. Alternatively, a small additional external pole excitation machine can be implemented to cover the rotor’s power requirement without brushes.

If electric current is then also taken from the induction coil, i.e. electric energy is generated by the generator, a counterforce is created which brakes the movement. The greater the electrical power taken, the greater the necessary mechanical drive power. In contrast, an electrically unloaded generator hardly brakes the drive source at all.

There are also electrostatic generators that do not use magnetic fields. However, these are very rarely used and are only suitable for very low power.

There is a wide range of different generator designs, adapted to the respective applications. Depending on the design, a generator produces alternating current (possibly also in the form of three-phase current) or direct current. Direct current is obtained by rectifying the originally generated alternating voltage, either internally through a commutator (electrical contacts which periodically reverse the direction of connection of the rotor coil in the external pole generator) or through an external rectifier.

power efficiency

Synchronous Generator Working Principle

READ NEXT: Starting Current : Guide, Background Information and 5 Valuable Tips

Synchronous and asynchronous generators

Some AC and three-phase generators operate synchronously, i.e. their speed is fixed by the frequency of the power grid to which they feed. Such synchronous generators are used almost exclusively for high power. However, smaller generators often operate as asynchronous generators, where there is a certain speed slip: They turn a little faster, especially when operating at high power. This results in a certain loss of power efficiency, especially with smaller generators.

Another disadvantage of the asynchronous generator is a certain amount of reactive current. But in return it is particularly simple to build and robust. Synchronous generators are often designed so that an adjustable reactive power can be generated.

asynchronous generator

Asynchronous Generator Working Principle

READ NEXT: Discover How Inverter Power Generator Works

Relationship between speed and number of poles

A high number of poles is required to operate a generator at low speeds.

With alternating current and three-phase generators there is (just like with motors) a more or less fixed relationship between the speed and the mains frequency, which however also depends on the number of poles (= 2 – number of pole pairs): The speed of the magnetic field (rotating field speed), which in the synchronous machine corresponds exactly to the speed of the rotor, is the mains frequency divided by the number of pole pairs.

 For example, the minimum possible number of pole pairs 1 at 50 Hz mains frequency results in a rotating field speed of 50 / s = 3000 / min, i.e. 3000 revolutions per minute. With two pole pairs, the speed drops to 1500 rpm, whereas 2000 rpm cannot be achieved.

Slow-running generators, e.g. in hydroelectric power stations and gearless wind turbines, must have a high number of poles. In contrast, turbogenerators driven directly by turbines are usually two-pole or sometimes four-pole.

Permanent excitation and electrical excitation

Small generators (such as bicycle dynamos) are usually permanently excited, i.e. the magnets used are permanent magnets (permanent magnets). For very large generators in power stations, practically only electrical excitation (external excitation) is used, i.e. electromagnets are used.

A part of the electrical energy produced is thus used for excitation, but this part can be quite small (for large generators well below 1% of the power produced), as the coils of the electromagnets have a low electrical resistance.

When starting an electrically excited generator without an external energy source, there is in principle the problem that initially there is no energy available to operate the exciter. However, at least a small residual magnetic field remains from the previous operation, which at least allows a small induction voltage. This now causes a small current through the exciter coil, so that the magnetic field and thus the induced voltage continues to increase.

The generator can be started in a short time even without an external energy source. The basic principle described is known as the dynamoelectric principle.

In the meantime, generators with outputs of several megawatts, as used in particular in wind turbines, are also designed with permanent excitation. This is made possible by the use of high-performance neodymium magnets and allows both a compact design and (due to the particularly strong magnetic field) operation at very low speeds, so that even a gearbox can be dispensed with.

Smaller versions of such generators are also used in vehicles with hybrid drive, for example. Unfortunately, however, the extraction of neodymium in mines (currently largely in China) is a very polluting process, as the ore contains many undesirable other substances, some of which are very toxic and some of which are radioactive. In addition, bottlenecks in the supply of rare earths such as neodymium threaten.

It should be noted, however, that mining activities could be made more environmentally friendly in the future and that at the end of the life of such a generator, the entire quantity of the neodymium contained can be recycled, as this material is not consumed.

Another possibility is electrical excitation with superconducting coils, which became practicable with the development of high-temperature superconductors (HTS). In this case, there is no need to use electrical energy for excitation, since the current can flow through the coils without any resistance. However, energy is required for the operation of refrigerating machines to cool the coils sufficiently to achieve superconductivity. Nevertheless, the power efficiency can be quite high. In addition, this principle enables a particularly compact design.

Power efficiency

Energy losses in a generator are mainly caused by the electrical resistance of the coils (ohmic losses, copper losses) and by generated unwanted eddy currents in iron cores (iron losses), additionally also by mechanical friction and air resistance as well as in larger generators by the energy expenditure for cooling equipment.

 However, large stationary generators achieve very high power efficiency of often more than 98 % or even 99 %. Generators with superconducting coils (see above), which are very power efficient and can be built smaller, are now being developed, especially for supplying ship propulsion systems.

Applications of electrical generators

The main applications of electric generators are:

  • The vast majority of electrical energy is produced by generators, especially turbo generators.
  • In most power plants, electrical energy is generated in one or more generators from mechanical energy. This is especially true for hydroelectric power plants, wind turbines and all types of thermal power plants, regardless of whether the heat is produced by burning fuel or in a nuclear reactor. In the case of thermal power plants, turbo generators are practically always used.
  • In electric cars and vehicles with hybrid drive, the drive motor usually serves as a generator for the recovery of braking energy (recuperation) during braking, which can be used to charge the vehicle battery (accumulator). Similarly, most electric locomotives can use the motor as a generator and feed braking energy back into the overhead line.
  • In vehicles with combustion engines, an on-board alternator generates the necessary electrical energy, unless a larger generator is already available through a hybrid drive. In bicycles, a small dynamo of very low power is used, which today is often designed as a more power efficiency and reliable wheel hub dynamo.

READ NEXT: Generator Transfer Switch

Typical characteristics of electric generators

Generators can meet a wide range of requirements, depending on their design:

  • Electrical outputs between less than one watt and significantly more than one gigawatt are possible.

  • Particularly large generators (e.g. in power plants with outputs of hundreds of megawatts) achieve very high power efficiency of sometimes more than 98 %. A high degree of power efficiency is possible over a wide range of outputs, i.e. also in partial load operation.

  • Depending on the design, a generator produces direct current, alternating current or three-phase current, and it can be driven at constant or variable speeds.

  • Many generators can also be operated as electric motors. One then often speaks more generally of electric machines.

  • The service life of a generator is usually very long (often many decades), as long as certain problematic operating conditions (e.g. severe overload, excessive speed or failure of the cooling system) are avoided.

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Predator 8750 Generator Review & Best features

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Predator 8750 Generator

Predator 8750 Generator

The predator 8750 generators is a heavy duty engine designed for people with high power requirements. The 7000 running watts, 13 horsepower generator is the best alternative during a power outage. The 420cc air-cooled OHV gas engine has a 12-hour runtime at 50% capacity. This generator can be a great deal for farmhouses or powering several houses.

Although this power generator can be a little bit costly for many people, the price is still good as compared to other brands that offer the same capacity. Apart from being used for normal purposes such as power backup, for farm applications, job sites, and recreation, it can also be used for starting up low-voltage equipment. Let’s see what sets this predator generator apart from the rest.

READ NEXT: Predator 4000 Generator Review 

Best features of Predator 8750 Generator

Looking at the features of this gas engine, you can easily have a slight idea of what to expect once you purchase the unit.

Energy Efficient

Just as mentioned earlier, the generator has a 420cc air-cooled OHV gas engine. It runs on 87+ unleaded gasoline and is designed to automatically shut down whenever the oil is low for the engine’s protection. This unit does not consume a lot of fuel. It has a capacity of 6.6 gallons and can run half a day powering several appliances. The efficiency of its engine is what saves you money.

Compact Design

Next time you’re out there looking for a generator to buy, always try and consider its design. With the predator 8750, its design is great and is not defined by the amount of power it produces. You might be thinking that since it is capable of producing 7000 watts, then it must be a very big unit. That’s not true. Although it weighs quite more than its predecessors, it has an adorable design. Also, note that it has a steel frame that protects the internal components.

Powerful

The EPA certified predator 8750 generator is one powerful engine with multiple outlets. To see how powerful it is, the predator has two 120V, 3 prong 20A duplex outlets, one 240V, 4 prong 30A twist lock outlet, one 120V, 3 prong 20A twist lock outlets, and one 12V DC outlet. There are also circuit breakers meeting UL specifications. Note that the generator produces 7000 running watts and 8750 starting watts.

Adaptable

The beauty of predator generators is that they are versatile. You can count on them on several functions. This predator 8750 is also dynamic and can be reliable on various functions. What a nice feeling knowing that your generator can be useful whenever an emergency arise or you’d like to go on a road trip with it.

Predator 8750 Generator
                                               Predator 8750 Generator

Pros

Easy to operate

It is good to know that you’ll not encounter difficulties in operating this gasoline engine. The predator 8750 generators have a friendly interface and therefore you do not need to have any qualifications to use it. Everything is indicated and in case you’re missing out on something, just pull out the user manual and check.

Quick Start

This should be interesting. The start-up time is very short. All you need to do is grab the ripcord and steadily pull it. There is also an electric start that you can opt to use although you’ll be required to buy a battery separately.

Low maintenance

Some generators need a lot of things done just to maintain them. It is a different case for the predator 8750 generators. Apart from requiring low maintenance, it’s also easy to take care of it. All you need is to do regular cleaning and taking care of the engine oil. The user manual is there to help you in doing all that. There is nothing more to be done in terms of maintenance.

Durable

Never go for a low-quality product that will cost you even more because of time to time repairs. The Predator 8750 has a sturdy construction that guarantees you the value of your money. If you handle it in a proper manner, this unit will last for a long period of time as it is designed with steel.

Safe and reliable

The generator is not only easy to operate, but also safe and reliable. There are air-cooled circuit breakers that guarantee the safety of its users by preventing fires. It is also reliable as it offers power for nearly half a day.

Cons

Bulky

The weight of this unit is a big challenge as moving around with it is quite difficult. The product weighs 220 pounds which makes it heavy. If you mostly move around, then this is not the best for you.

Not budget friendly

As much as it is a powerful generator that costs a little lower as compared to other brands of the same capacity, this engine is not affordable for all. Also, note that the wheel kit and the electric starter battery are purchased separately adding to its cost.

Noisy

This generator is quite noisy during its operation as compared to the other models. So it may not be that friendly when you need tranquillity.

READ NEXT: Our pick of the best Predator Generator

Predator 8750 Generator
                                         Predator 8750 Generator

What You Should Consider While Selecting Predator 8750 Generator

Energy Efficiency

A good generator should be energy efficient to minimize losses. If a generator is not capable of adjusting its speed to the load, then it won’t burn the fuel as required. Thus its power output will be affected. It’s therefore idle to consider the efficiency of a generator before purchasing it.

Durability

What’s the average lifespan of an engine that you wish to buy? You should consider this factor before settling for one. You don’t want to keep repairing your generator every now and then.

Maintenance

How often will you be required to do the maintenance thing? You’ll therefore need to check a generator’s maintenance needs and ensure that you’re comfortable with it before buying it. Traditionally, engines require maintenance and the predator is not an exception.

Energy Capacity

Different models produce different amount of energy. Knowing your energy needs is important to determine which model is suitable for you.

Portability

If you plan to move a lot, then go for a model that will facilitate exactly that.

Safety and ease of use

As you may already know, your safety comes first. Make sure the model you decide to purchase has safety precautions well highlighted. You should also consider the safety of your appliances by making sure they match with the generator’s power supply. Additionally, check that the generator is easy to operate, although this is not an issue with the predators.

Price

Finally, the price of the generator of your choice should be within your budget. Remember this is one of the most critical factor that may affect your financial stability.

Final Verdict

If you need to run multiple high voltage appliances, the predator 8750 generators are the best option. It will enable you to have uninterrupted power supply whenever you need it. This engine is known to produce a large amount of energy in a steady way. It is a better choice for power backups.

The multiple outlets make it a reliable power source for heavy-duty appliances, or high voltage machinery. The combination of great features and awesome advantages makes this generator to give other similar generators from different manufacturers a run for their money. As much as there are a few shortcomings with this model, there are more positive reasons to give it a try. The most important thing to do is always do your homework before purchasing one. Check the retailer’s warranties and other important stuff. Don’t forget that your power needs should be what determines the size of the generator to purchase.

Starting Current : Guide, Background Information and 5 Valuable Tips

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The term “starting current” is used regularly in connection with power generators. In addition, we know from our daily business that especially newcomers to the world of mobile power generation often find this topic difficult to deal with or there is a general lack of knowledge. The non-compliance with a few important rules can however quickly become a major problem for any power generator, since in the worst case capital damage is imminent.

Why is the starting current important?

Certain consumers (which ones, we will discuss in more detail in the next paragraph) require a multiple of the actual rated power when starting. These power peaks are only called up for a short time, BUT they have to be controlled by the power generator.

Conventional generators, e.g. simple converters, can still handle these peaks relatively well. These devices do not have such sophisticated electronics as the more advanced inverter power generators. The simpler design of the converters is more resistant to overload, but these devices cannot deliver a clean and harmonic sine wave voltage in mains quality as the inverter generators can. In general, the following can, therefore, be stated: Too high starting currents can bring generators to their knees. Even severe damage cannot be excluded.

Therefore it is essential to deal with the starting-up currents of the consumers in depth. With the information on this page, the search for a sufficiently powerful generator will be much easier. But what types of consumers are there and do all of them have the dreaded starting currents?

starting current

READ NEXT: Best Power Efficiency Guide For Generator

Do start-up currents occur with all consumers?

Basically, three groups of consumers can be distinguished.

Ohmic loads

Radiators, construction radiators or hotplates can be added to this class. They are defined by the fact that the power consumed (watts) is converted into brightness or heat. Therefore they are also called active power consumers. For the electric generator, this class is the least problematic, since with Ohm’s consumers the output power corresponds exactly to the input power from the electricity generator. Or to put it in a nutshell: Ohmic consumers have no starting current.

Inductive consumers

The next big class are the so-called inductive power consumers. These include electric hand tools (chain saw, drill, compressor, circular saw, etc.). Here the matter becomes a little more complicated. These devices have their own built-in motor and this has to “get going” first – and this is where the infamous start-up current comes in.

Let us imagine a bicycle that has to be accelerated quickly from a standing position. This requires a little extra power in the calves. But once the bike has started to move, it is noticeably more comfortable. The starting behaviour of an inductive consumer is similar.

Before buying a generator, you should therefore be aware of the following points:

  • What is the rated output of the consumers I plan to connect?

  • Do these consumers need a starting current when starting?

  This information can be found in the respective manual. It may be necessary to contact the manufacturer, who will be able to provide the exact characteristics. Tip: Considering the performance of the generator, allow for some “air up”. 20 to 30 % is optimal. On the one hand, this protects the engine (= extension of the product life), on the other hand, the operating volume of the generator is significantly reduced.

Capacitive consumers

This is probably the most critical group of consumers, but fortunately very few will come into contact with these consumers. Examples are discharge lamps or flashlights that have a charging function. In order to satisfy their hunger for electricity, special extra equipment is needed: a Barber-Colman regulator. “Normal” power generators, which are mainly available on the market, will not be able to provide the required starting current of a capacitive consumer.

READ NEXT: Generator Transfer Switch

Can the starting current be calculated and how long does it last?

That would be nice, of course, but unfortunately, it does not quite work that way. The individual consumers and their motors are too different. As a rough value, however, the 2 to 6 times the value of the actual rated power has become common.

In the following, we would like to give a few concrete examples from our everyday business to give a better picture of the dimensions:

  • Metabo crosscut and miter saw KGS 216 M, rated power 1500 W, 3 times the starting current, thus 4500 W for a short time

  • Gardena 4000/4 electronic domestic water dispenser, rated output 800 W, approx. 3.5 times the starting current, therefore 2800 W for a short time

  • Makita chain saw UC4020A, rated power 1800W, 3 – 3.5 times starting current, thus briefly up to 6300 W

But how long must an electricity generator be able to handle these power peaks? The duration of the starting current differs greatly from consumer to consumer, so that unfortunately no exact specification is possible at this point. Usually, it is “only” a fraction of a second, we are talking about milliseconds. Even in extreme cases, the motor reaches its target speed after a few seconds.

What is the best way to deal with the dangers of starting current?

The best advice here is: Inform sufficiently in advance is everything! This is the only way to make the right choice of an adequately dimensioned generator. The most important key data are the rated power of the loads to be connected and whether a starting current occurs (inductive loads). If this is the case, studying the product instructions or asking the manufacturer will help. With this information you are on the safe side and a correspondingly powerful generator should be found quickly.

Modern devices, such as inverter generators, usually come with an overload protection. In case of too large power demands (e.g. starting current) this trips and switches off the power generator before major damage to the sensitive electronics occurs. However, the overload protection should never be intentionally overloaded in the long run to avoid damage to the device.

Also the possibility of starting current limiters (also called soft starters) should be mentioned here. These devices limit the current peaks and thus protect the electronics of the power generator from fatal overloads. Specialist dealers and a relevant online sales platform will help you find what you are looking for.

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8 Inverter Power Generator Tips: Discover How It Works

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Introduction to the world of the inverter power generator

Nowadays almost nothing works without electricity. We have all gotten much too used to this luxury and we only notice how dependent we have become when there is no fixed power socket nearby. Mobile power generators have practically infinite possibilities. During a longer blackout as an emergency power supply, when traveling with a motorhome, in the garden at home, on building sites, during a festival visit, on boats, when camping or as a welcome power supplier at open-air events: On all these occasions – and countless others – mobile power generators play out their full strength. No wonder, then, that these handy power plants are becoming increasingly popular.

In the search for a suitable device, the term “inverter technology” is being used more and more often. The innovative inverter power generators will sooner or later dominate the market of mobile power generation due to their characteristics and advantages over conventional power generators (converters). Nevertheless, not everybody can imagine anything under this technology, especially if you are not yet very familiar with this matter. Also our customer service regularly receives calls and mails on this topic. Therefore, in this guidebook, we dedicate ourselves entirely to the question of what the features and advantages of this technology are and how an inverter power generator works.

Champion 3400-Watt Dual Fuel RV Ready Portable Inverter Generator with Electric Start Pulsar G2319N 2,300W Portable Gas-Powered Inverter Generator with USB Outlet & Parallel Capability, CARB Compliant, Gray

Features and advantages of an inverter power generator

What does the term “inverter” mean anyway? The easiest way to translate “inverter” is to say “inverter” because it converts direct current reliably into alternating current. The great advantage of this technology is that at the end of this process a perfect and pure sine wave voltage is delivered. Quasi electricity with the constant high quality of a house socket.

This results in many advantages for the consumer. For example, the inverter power generators guarantee a clean power output always and everywhere, as dangerous voltage fluctuations are prevented. Therefore even highly sensitive electronic consumers (e.g. laptop, TV set and music system) can be operated without any problems. Conventional power generators without inverter technology, however, can damage or even destroy them.

In addition, the inverter power generators are able to adjust their speed downwards accordingly in partial load operation. In the practical eco mode, the engine speed is optimally adapted to the amount of electrical energy required, i.e. the mobile power generator runs much more quietly at the push of a button and less fuel is consumed. And this is good news for both your wallet and the environment.

How an inverter power generator works?

An important feature of inverter generators is that the combustion engine and the generator work independently of each other. Or in other words: They can run at different frequencies. The downstream inverter electronics finally ensures that the current produced by the generator is output with a harmonized and stable sine wave voltage.

Now that you have gained some theoretical background knowledge about an inverter power generator, it’s time for one of our blue guys to literally drop his pants for you.

Therefore we present you a 3D sectional drawing at this point. Thanks to it you can see very well how the inner workings are and how an inverter generator works.

inverter power generator

Working of inverter power generator

1. Display:

The clearly arranged LCD display informs about all important performance data at a glance. This includes, for example, the voltage delivered, the current power or the total number of operating hours completed. The oil level can also be easily checked here. Thanks to the backlighting, the power generator is also suitable for use in the dark – for example, for a hip party under the stars.

2. Sockets:

Consumers with 230-volt alternating current are connected to the Schuko sockets. Inverter power generators with sufficient power potential often even have two sockets to be able to operate several consumers at the same time. This means that there is no longer any dispute about who may first take possession of the handy mini power station. When buying a mobile power generator, make absolutely sure that the sockets have at least IP54 protection class (protection against splashing water). High-quality generators also have a connection for 12-volt direct current. This is particularly practical if, for example, an empty mobile home battery needs to be charged while on the move.

3. Starter battery (also accumulator):

The starter battery stores electrical energy and releases it when needed. If your new inverter power generator is equipped with this feature, the starting process is more comfortable than ever: Simply press the ignition button and turn the key and you have your personal power to go. And all this without breaking out in a sweat from starting with a pull starter.

4. Electronics:

On this board is the inverter. Practically nothing works without this important component, because it converts the direct current coming from the generator into clean alternating current with a pure sine wave. Only in this way can sensitive electronic devices (e.g. laptop, music system or television) be operated safely. Because unlike a conventional power generator, an inverter power generator reliably protects these consumers from serious damage.

inverter power generator

Working of inverter power generator

5. Cooling fins:

The combustion process in the engine generates heat which must be dissipated as quickly as possible. For this purpose, a fan wheel rotates in the operating state, which dissipates the heated air. Its path leads past aluminium cooling fins, which reduces the temperature of the air. This is based on the physical principle of enlarging body surfaces in order to improve heat transfer to the environment and thus cooling overall. This prevents the engine from overheating so that the generator can remain in operation as long as you wish.

6. Motor:

Here you can see a 1-cylinder 4-stroke engine of the latest generation with automatic easy start. An important quality feature is the overhead camshaft. The engine is the heart for the function of an inverter power generator. By means of an automatic speed control, it adapts itself optimally to the “hunger for electricity” of the respective consumer. You benefit from this in two ways: Significantly less fuel is consumed and, in addition, the inverter power generator works as quiet as a whisper.

7. Encapsulated housing:

Conventional generators with open frame construction are loud and clumsy. You should therefore prefer the more advanced inverter power generators, because they are much quieter and run more smoothly due to the encapsulated design. The high-quality insulation materials also contribute to optimal sound absorption. By the way, a consistent lightweight construction runs through the inverter power generators and ergonomically shaped components are used, so that transport is easy.

8. Carburetor air filter unit:

Here first the fuel is finely atomized. Then it is brought together with the already pre-filtered air. The fuel-air mixture now has the perfect composition for the subsequent explosion. This takes place in the combustion chamber – and the inverter power generator already begins its work.

9. Fuel tank:

This tank holds the fuel necessary to run the engine. Petrol-driven inverter generators are quieter and smoother than their diesel-based counterparts and are also cheaper to buy. The size of the tank is of course a decisive factor in how long an inverter generator will run without refuelling. Depending on the connected consumers, top-of-the-range devices can run for up to 14 hours with just one tank filling.

10. Cable starter:

This mechanical cable starter is also called a reversing starter. With a cable pull, combustion engines with a rather small displacement can be started quite easily. Just pull the cable 1-2 times and the inverter power generator starts. Of course, the pull-wire starter also offers a certain safety aspect: If the starter battery fails, for example because it is discharged, the power generator can still be reliably started.

11. Manual fuel pump:

The manual fuel pump makes starting a car much easier, especially after long periods of standing still. Each time the pump is actuated, a little petrol flows into the carburetor due to the negative pressure. Press a few times and the inverter power generator purrs like a kitten.

Summary

How does an inverter power generator work? After reading this guide, you can answer this question easily. You now also know the main reasons why inverters are considered to be the most innovative devices on the market: they generate electricity on the move with the quality of a household socket so that even voltage-sensitive consumers can be connected without worrying about damage – and they are quieter and produce fewer emissions than conventional power generators.

Technology fans also got their money’s worth in the section where the inner workings and functionality of an inverter power generator are explained in detail. We hope that you enjoyed this technology excursion and that you now feel well informed.

If you still missed one or the other point, please contact our customer service! There all your questions will be answered competently.

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