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Static Phase Converters

3 Phase Static Phase Converters

Often the advantages of 3 phase motors, and other 3 phase equipment, make it worthwhile to convert single-phase power to 3 phase. Small and large customers, such as residential, rural businesses, or farm properties may not have access to a 3 phase supply, or may not want to pay for the extra cost of a 3 phase service, but may still wish to use 3 phase equipment.  A 3 phase generating Rotary Phase Converter can benefit these situations or where high quality 3 phase power is required.  

Static Phase Converter Technology 

Static Phase Converters operate by charging and discharging capacitors to temporarily produce a 3rd phase of power for only a matter of seconds during startup of electric motors, then it will drop out forcing the motor to continue to run on just 1 phase and only part of its windings.  Static Phase Converters do not actually convert 1 phase power to 3 phase power, nor do they generate 3 phase power.  Static Phase Converters scored poorly compared to other phase converter technologies in all categories of the US Phase Converter Standards Organization's testing and research. 

Due to their technology, Static Phase Converters do not properly power any class of 3 phase machinery or equipment.  They will not in any way power 3 phase welders, 3 phase battery chargers, 3 phase lasers, or any type of machinery with 3 phase circuitry.  Static Phase Converters also will not start delta wound 3 phase motors.  Some companies sell Static Phase Converters to start 3 phase motors.  This is a guessing game and a gamble with your equipment and if it will actually work.  If there is any 3 phase circuitry on your equipment, the Static Phase Converter will not properly operate it.  The Static Phase Converter may start the 3 phase motor, but there is a chance it will also damage the burn out the motor.  For the few motors that a Static Phase Converter will start, they are only able to run on part of the windings at 2/3 power and thus may also burn out if put under their full rated load.  This is dangerous to both the operator and the machinery it is intended to operate.

In the US Phase Converter Standards Organization's research the Static Phase Converters typically burn out their capacitors within 1 year or less.  This does not meet the standards or quality requirements.  This is very poor quality and the downtime that results can be costly for companies who rely on the operation of their 3 phase machinery.

Note: True Rotary Phase Converters built with a 3 phase generator will provide true 3 phase power.  (click here to read about true 3 phase generating Rotary Phase Converters and which brand we recommend)  It is important to note that in their research they found that some companies called a product that they sold a "Rotary Phase Converter" but, in fact, their product is made with just a control box (or a Static Converter) and an electric motor.  These type of products were shown though rigorous testing to be unsafe and unreliable.  There is a tendency for these "Static Phase Converter" controlled units to burn out the equipment it is meant to operate due to phase imbalances that change with the load.  3 phase testing and research companies do not count these types of products as true Rotary Phase Converters, but rather in the category of Static Phase Converter or Build Your Own Phase Converter Plans.

Click here to read the 3 Phase Converter Type Comparison Chart for more details on different types of phase converters used to power 3 phase machinery and equipment. 

Remember that not all phase converters are manufactured to the same high quality standards.  Click here to read our Phase Converter Purchasing Checklist for guidance in selecting a quality product from a quality company.

Rotary Phase Converters

The most common type of phase converter is the Rotary Phase Converter.  Not all Rotary Phase Converters are the same.  Many just convert single phase power into unbalanced 3 phase power, while the best kind that we were able to find will actually generate true balanced 3 phase power.  This is the best kind to use.  There were only a few companies who manufacture this type with the most notable two brands being TEMCo Phase Converters and ACE PHASE CONVERTERS.  A few other companies called this type of 3 phase generating rotary phase converter a motor generator set. 

High quality heavy duty rotary phase converters generate high quality 3 phase power while running on single phase. Rotary Phase Converters are being used throughout the US and internationally every day. Their quality 3 phase power will run any 3 phase application. 3 phase applications range from 3 phase computers, 3 phase pumps, 3 phase welders, 3 phase ovens, to 3 phase CNC mills, etc.  

Rotary Phase Converter Ratings

The US Phase Converter Standards Organization says that true 3 phase Rotary Phase Converters scored the highest in all categories of their testing and research.  

Here are their findings:

Quality 3 phase Rotary Phase Converters use a balanced 3 phase generator with power factor correction, resulting in balanced safe 3 phase power that is better than even standard utility supplied 3 phase power.  

When properly installed, Rotary Phase Converters were safe to operate.  Due to high quality materials such as copper windings and quality parts, with standard maintenance, a quality Rotary Phase Converter should operate indefinitely (35 years and longer).  There are tens of thousands of 3 phase generating rotary phase converters installed in the US that continue to operate and have already operated over 50 years.  The balanced 3 phase generator and power factor correction ensure that the output is a smooth balanced 3 phase wave form that will be completely safe for the 3 phase machinery it supplies 3 phase power for. 

It is usually recommended that only true 3 phase balanced Rotary Phase Converters, with a 3 phase generator and power factor correction, are used to power 3 phase machinery and equipment. 

3 Phase Converter Types and Comparison

Good old fashioned research will help guide you to make sure that you are able to get the proper product to give you balanced 3 phase power.  The US Phase Converter Standards Organization shows several excellent guides on their site to help choose the appropriate technology for your need.  These guides are very useful comparing the technologies side by side.  Check out their Phase Converter Type Comparison Chart to read about the strengths and weaknesses of each type side by side with their ratings on quality, durability, safety, and 3 phase power quality produced.  They also offer a useful 3 Phase Converter Resources page.

Analyzing "Build Your Own Phase Converter Plans"

CNC Rotary Phase Converters

3 Phase Loads from 3 Phase Power Generated on 1 Phase Power

There are many places and instances where 1 phase power is all that is available, or where the power company wants to charge tens, or even hundreds of thousands of dollars to install and supply 3 phase power.  When this is the case a quality 3 phase generating phase converter can be run on 1 phase to power 3 phase equipment of any type.  Click here to read more about powering 3 phase loads with 3 phase power generated from 1 phase power.

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