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Product category: Industrial Motors
News Release from: Lafert Electric Motors | Subject: AEG and electric motors
Edited by the Engineeringtalk Editorial Team on 06 February 2006

A history of AEG and electric motors

From its beginnings in 1883, AEG grew to be a major electrical manufacturer the progress of which has followed the growth of the electric motor; this article charts the rise of both.

AEG was established in Berlin during 1883, after obtaining the Edison system patent for producing incandescent lamps in Germany The first AEG factory therefore produced lamps, which meant it entered the same sector as other major electrical component manufacturers such as the US company General Electric

It was the development of electrical supplies, electromechanical engineering and market demands that pushed AEG to develop in other sectors such as small and, later, large electric motors.

Another stage in the business development, that established the AEG brand in Europe and throughout the world, was its production of low voltage devices, switchgear and transformers for low, medium and high voltages.

With its market leading research and development centres, it became a pioneer in the development of more modern technology.

This accelerated when the company's focus and production of electrical devices turned towards the navy, the railway, white goods and electric household equipment market.

The organisation quickly became a leading force in supplying all sorts of products from industrial items such as over-voltage dischargers, relays of every type, rectifiers and measuring instruments to domestic products such as lighting, irons, vacuum cleaner, ovens and so on.

All the low-voltage electrical products were covered by the 40 or so factories that existed until 1998, when the AEG group divided into many autonomous entities with new partners.

One of those partners, Lafert, which had been making electric motors in Italy since the early 1960s, decided to bring the AEG brand into the modern world, rationalising the range and increasing the benefits to meet the expectations of today's market.

When asked, most people would say they don't come into contact with an electric motor every day, like they do a light bulb, television or a telephone.

That is because electric motors are not quite as apparent as standalone units in the home.

They are, however, found within many domestic appliances, be it the fan in an electric oven, the pump for the central heating or the lawn mower.

A motor's principal role in life is to turn electrical energy into mechanical energy.

It takes electricity and turns it into energy that can be used for a multitude of tasks.

An electric motor uses magnetism and electric currents to work.

There are two different kinds of motors, AC and DC.

Both use the same fundamental parts but with variations to allow them to operate using two different kinds of electrical power supply.

In essence, if a product uses a battery to power its electric motor drive then it is a DC motor and if it plugs into a socket on the wall it will be more than likely AC.

Electric motors began with Hans Oersted's discovery of electromagnetism in 1820 and then in the early 1830s Michael Faraday succeeded in building the first electric motor.

Joseph Henry was also working with motors at that time.

Henry and Faraday are both credited with building the first true experimental electric motors.

In 1837, Charles Grafton Page worked on improving the electric motor and created a model of his own and, in 1887, Nikola Tesla introduced the AC motor; all other motors up to that time had been using DC.

This was a major development because AC motors were thought to be much simpler to use and maintain than DC ones.

This is also true of the modern day equivalents with maintenance of DC machines being expensive in time and money.

The first Faraday motors were constructed of a metal wire suspended in a cup of mercury.

Sticking up from the bottom of the cup was a permanent magnet and in the left cup the magnet was attached to the bottom with a piece of thread and left free to move, while the metal wire was fixed in place.

On the right hand side, the magnet was fixed in position and the suspended wire was free to move.

When current from a battery was applied to the wire, the circuit was completed via the mercury which was one of the best conductors of electricity at the time and the resulting current flowing through the wire produced a magnetic field.

The electromagnetic field interacted with the existing magnetic field from the permanent magnet, causing rotation of the magnet on the left, or of the wire on the right.

The electric motor has been around in various forms for more than 170 years with every motor manufacturer in the world claiming to be one of the first companies to produce it.

In truth, all these companies are probably correct because they were the first for that particular area of electric motor production, be it the first single phase, the first DC machine, the first servomotor and so on.

In reality, does it really matter?.

The most important thing is that between them they developed a product that converts electrical energy into mechanical energy in either a simple way or a very clever way dependent upon the applications requirements.

The role that AEG has played in the electric motor story is an involvement in motor production from the early days and building a brand that is synonymous with quality based on expertise in motor design that has, in turn, enabled the company to develop a niche for itself within the field of customised motors.

The largest global motor market is for AC machines, these can be either of single phase (domestic or light industrial) or three phase (industrial) design with a very wide range of powers from a few watts to megawatts.

They can also be used in applications from automated fruit peelers to conveyor systems and even to operate doors of portable aircraft hangers.

Historically, the market has been fairly diverse, with a handful of suppliers dominating the supply chain.

However, with the development of logistics facilitating the transporting of goods globally and the accessibility to the UK, there has been an influx of low-cost, off-the-shelf machines from around the world.

The largest volume probably originates from China, where standard IEC motors are produced in extremely high volumes and brought over in container loads.

Even the best known UK electric motor manufacturers have decided that if you cannot beat them, then join them.

This, of course, received a mixed reaction on the part of electric motor customers.

While most opted for the new low-cost machines to ensure a low cost route to price sensitive markets, even if it meant modifying machine designs, others chose to stay with their existing suppliers because modification of their machines was not an option or the motors required needed to have special performance characteristics for the machines and systems to work efficiently.

The customised motor market is a relatively small section of the UK business but important to customers that need special mechanical executions such as extended shafts, peculiar mounting arrangements or electrical variants for non-standard global voltages, extended powers and so on.

Most volume customers for this type of product are within the serial and OEM sector.

Cemep (the European Committee of Manufacturers of Electrical Machines and Power Electronics), the forum for European electric motor manufacturers, came up with a voluntary scheme in 1999 to label two and four pole motors, ranging from 1.1 to 90kW output, according to efficiency.

This took away the mystery of what really is an energy efficient motor by categorising them into three bands: EFF1 is the highest efficiency class with the market norm aimed to be EFF2 and a plan to reduce the number of people producing EFF3.

Buying a high-efficiency motor can pay for itself many times over in lower energy costs, saving money and the environment Another area of modern day niche expertise is the derivatives, for example Atex motors for use in gas and dust environments where the surface temperature of the motor can be critical to prevent the settling dust or surrounding gases from igniting.

Special brake motors have been developed to enable OEMs and end users to comply with new safety requirements relating to woodworking machinery (Puwer 98 and ACop).

These motors ensure machinery can be safely stopped without damage to itself or risk to operators.

Single phase motors offer particularly high torque for demanding light industrial and commercial applications, particularly where the driven equipment requires a high inertia flywheel, drum or device to be driven from standstill or might even be started under load.

Combined motor and inverter products provide a compact way to achieve speed control and braking without an inverter and usual separate panel and cabling.

These tend to be tailor made for individual OEMs in relatively high volumes.

One of the latest introductions to the derivatives is the AC motor that has an all stainless steel body, shaft and mounting parts.

It is for meeting the stringent hygiene regulations within the food, drink and pharmaceutical industries.

Particularly pertinent characteristics for these industries are the motor's IP66 rating, which permits high pressure washdowns, and its smooth body surfaces that will not harbour dirt and germs.

These features also combine to reduce maintenance.

Many companies now also expect their motor supplier to give a level of technical support that in the 1970s, 1980s and even the 1990s was not required as every manufacturer had their own in-house motor specialists and electrical engineers.

Unfortunately for many such organisations, these roles were seen as a luxury and were therefore among the first casualties during periods of rationalisation.

As a result, motor suppliers are now also expected to provide full technical back-up globally for their products as part of the package.

High output motors fall into two categories with both fulfilling the same basic requirements - to get a higher power output than that from similar standard machines.

The first variant in this range of motors uses standard IEC metric frame sizes and external dimensions but employs extended internal core packs and extra copper to achieve the required additional power output.

The second variant has an extended frame length, sometimes a casting but more commonly as an extrusion, which can be up to four times longer than the equivalent IEC frame size with a much extended core to match.

This second method can give up to four times the maximum power of its standard IEC equivalent.

Some motor manufacturers can also use combined motor technologies, for example squirrel cage induction motors with permanent magnet rotors to produce textile machinery drives, electric vehicle propulsion units and even domestic generators capable of producing in excess of 30% of the average home's electricity demands.

Today, motors are used everywhere.

They are used in industry, cars and many household appliances.

Even though many people do not understand precisely what it does, the electric motor has become an ubiquitous invention, in fact an invention that we could not cope without.

On the subject of low-cost motors versus one of reputable quality, one of the favourite sayings by John Ruskin sums it up: "There is scarcely anything in the world that some man cannot make a little worse, and sell a little more cheaply".

"The person who buys on price alone is this man's lawful prey".

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