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3 Phase Frequency Converters

3 Phase 50 Hz, 60 Hz and 400 Hz Frequency Converters

Frequency Converters, also known as Motor Generator Sets (MG Sets), are used for converting either 50 Hz, 60 Hz, or 400 Hz, utility line power to 50 Hz, 60 Hz or 400 Hz power to run equipment. In addition to this some frequency converter manufacturer's, namely TEMCo, Frequency Converter MG Sets also offer line isolation, harmonic cancellation, power factor correction, phase conversion, voltage conversion with balanced, smooth, controlled power output. Typical applications include AC variable speed drives, inverters, computers and computer controlled equipment, deep well pumps, industrial machinery, ships, aircraft, military computers and many more.  

(published with permission by TEMCo Frequency Converter Division)

What are the differences between a "Solid-State" frequency converter and a TEMCo Motor Generator Set Frequency Converter?

Unlike "Solid-State" frequency converters which convert your incoming 50 or 60 Hz AC power to DC then chop it back up to output a synthesized AC sine wave, the TEMCo Frequency Converter Motor Generator Sets produce a true sine wave form, perfect and smooth in every way.

Synthesized AC, as produced in solid state devices, is a rough spike laden attempt at AC power which rarely comes even close to resembling the pure, smooth wave most modern equipment was meant to run on.  Solid State Frequency Converters power output can be harmful to sensitive equipment and cause the lifespan to be greatly reduced.  This is why it is better to use a true power generating Motor Generator Frequency Converter.

TEMCo's Frequency Converters Provide Harmonic Cancellation

Harmonics cannot, in any way, be transmitted through TEMCo Frequency Converter Motor Generator Sets because the only connection between the input and the output is mechanical not electrical. It's the shaft.

TEMCo's Frequency Converters Provide Electrical Line Isolation

One major advantage of using TEMCo Frequency Converter Motor Generator Sets is that, unlike other means of frequency and power conversion the output of TEMCo Frequency Converter Motor Generator Sets will remain stable through anything short of complete black out or disconnection, regardless of your utility supplied power condition.

Your line power may suffer from brown out conditions, transients, spikes etc., however, TEMCo's Frequency Converter MG Set will not deviate from the rated frequency. The output remains constant.

In fact the actual output of a TEMCo Frequency Converter Motor Generator Set is often better than what you would normally see on your utility grid. Unlike your industrial community power, where you have no control over what your neighbors do with it and how that affects your supply, using a TEMCo Frequency Converter Motor Generator Set is like having your own power generation plant right in your facility.

Many commercial utility consumers report that other users connected to the same power grid cause momentary brown outs, surges, poor power factor and harmful transients to their power by simply switching on and off large industrial loads. This can be as simple as the voltage spike and back EMF that happens when contactors (commonly called motor starters) switch on and off large motors on factory equipment. These spikes can momentarily exceed 800 Volts on a 240V line. This is just one example of the dangers that lurk in the commercial utility system environment, but the scenarios are countless. Unless something is put in place to stop these power conditions from reaching your machinery then they will take the impact in full force.

Simple motor type loads may last a while and are fairly resilient under such conditions but over time this can cause insulation brake down then ultimately and inevitably complete failure. Sophisticated loads such as solid state devices, CNC machinery and all computer controlled loads cannot handle these situations; results are usually terminal on the first occurrence.

TEMCo's Frequency Converters Provide Power Factor Correction

TEMCo Motor Generator Sets can automatically compensate for power factor robbing equipment. This helps considerably when loads are complex, unbalanced or non linear. Remember that good power factor is essential to the electrical health of your hardware and contributes heavily to the operational efficiency. 

TEMCo's Commitment To Quality Demands The Best Manufacturing Materials

TEMCo has insisted on exclusively using copper in our Frequency Converter MG Set windings. Why? - Because of our commitment to quality. Copper, due to its inherent high conductivity, ductility, and strength, has always been the ideal material for conducting electricity. All TEMCo MG Sets are manufactured with only pure electrolytic copper windings. The following are the reasons why: 1) The conductivity of annealed copper is set equal to 100%. This means copper provides more current carrying capacity for a given diameter of wire than any other engineering metal. 2) Copper resists corrosion and creep. It will not lose strength or conductivity under conditions of high humidity nor will it break down. The protective oxide which forms is a good conductor of electricity. 3) Copper has excellent thermal conductivity and therefore stays cooler during current flow. This saves energy and promotes the dissipation of heat. Other companies may take compromise to cut costs, but TEMCo is committed to quality in every way!

TEMCo's Frequency Converters Have Versatile Power Output

Most TEMCo Frequency Converter MG Sets can be field reconfigured for 90 through 600 Volts AC output and fine adjusted to fractional volt accuracy. This means one machine can be reconfigured to sserve multiple purposes. 

Common Frequency Converter Configurations Include:

50 Hz or 60 Hz Input
50 Hz, 60 Hz, or 400 Hz Output
120 Volts through 600 Volts Input
120 Volts through 600 Volts Output
1 or 3 phase Input
1 or 3 phase Output
6 kW through 200 kW

Definition of a Frequency Converter

A frequency converter can be single or 3 phase and also change voltage thus functioning as a power converter from 60Hz to 50Hz, from 50Hz to 60Hz and from 50 / 60 Hz to 400 HZ.  A frequency converter can be used for continuous duty or testing products designed for export.

Several types of rotary frequency converter will monitor the input voltage, and in the event of long term power failure (which can even result in an under-frequency situation or a brownout), the logic will disconnect the load from the generator and shut down the unit.

In normal operation, the Rotary Frequency Converter acts as a rotating filter against utility transients. In general, it is 100% effective for outages less than approximately ½ second.  The absence of brushes and slip rings in the Motor Generator Frequency Converter allows for virtually maintenance free operation.

400 Hz Frequency Converters

Motor Generator Rotary Frequency Converters are a very important part of the aircraft ground support, computer and maintenance facility industry. 400 Hz Frequency Converters are designed to meet power requirements of the latest military commercial aircraft as well as 400 Hz avionics, missile, computer, radar equipment and other frequency changing applications.

3 Phase Power Is More Efficient Than Single Phase

Three phase electricity powers large industrial loads more efficiently than single-phase electricity. When single-phase electricity is needed, It is available between any two phases of a three-phase system, or in some systems , between one of the phases and ground. By the use of three conductors a 3 phase system can provide 173% more power than the two conductors of a single-phase system. Three-phase power allows heavy duty industrial equipment to operate more smoothly and efficiently. 3 phase power can be transmitted over long distances with smaller conductor size.

Variable Frequency Drives Used To Control Motor Speed:

Variable Frequency Drives and Soft Start Drives are not actually used to change power frequency, but instead are used to control motor speed for applications that need a motor to speed up or slow down.  If you need to change power frequency see above for Frequency Converters. 
 

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