General Information about phase converters:
  • Static Phase Converters
    these straightforward units will start a 3 phase load but run it only under single phase power. The load is limited to about 2/3 of its rated capacity.
  • Rotary Phase Converters
    these much more sophisticated units create true three phase power supply, often more precise than utility-supplied three phase power. 

Who can use a Rotary Phase Converter?

Rotary phase converters are most commonly used in commercial, industrial, and residential settings to power three phase equipment when utility 3-phase power is either too costly or not available. Rotary phase converters convert single-phase power into balanced three-phase power. Rotary phase converters are a very cost-effective way to power three-phase CNC equipment, and they come with simple and easy to use installation manuals. Rotary phase converters are rated using the maximum horsepower that they can handle. Due to the consistent voltage balance, the electric motor will operate at or near its full horsepower capacity. The output is custom balanced to meet the requirements of CNC equipment as well as other loads.

How much electricity does a phase converter use?

A rotary phase converter, by itself, is in an idle state and draws only the amount needed to keep it energized. This is only a few kilowatts and in some cases is less than a kilowatt. Your true electrical consumption is based on what the load draws. The rotary phase converter is merely a device electricity passes through on its way to your load.

Can I run a 480 volt piece of equipment on an American Rotary phase converter if my single phase voltage is 240?

Yes, however, a transformer is also needed. A rotary phase converter produces a three phase voltage identical to its input voltage. For example, if your input is 240 volts single phase, then your output is 240 volts three phase. The rotary converter does not change voltages. In this case, a step up 3 phase transformer (240 volt to 480 volt) is needed after the phase converter.

What type of maintenance is required for a rotary phase converter?

An America Rotary phase converter is very dependable and maintenance free. Bearing grease may occasionally be needed.

How large of a single phase service do I need?

Your single phase service required is dependent on the loads connected after the phase converter. America Rotary phase converters will run on a range of input amperage. As a general rule, determine your 3 phase load amps and double for your single phase feeder amps.

What else do I need with a rotary phase converter?

Generally speaking, you will need wire, conduit, connectors and a single phase power source, such as a circuit breaker or disconnect switch. More materials may be needed depending on how elaborate your output connection is between the load and phase converter. American Rotary offers a full line of electrical components to make your installation easy, professional, and safe.

What does CNC mean? Can an America Rotary Phase Converter run a CNC machine?

CNC stands for Computer Numerical Control. CNC equipment has a computer that can be programmed to run the operation of the machine. Computer operated machines are generally very voltage sensitive. The American Rotary Smart Series Rotary Phase Converter has +/-5% voltage balance to run these types of machines.

Will my machine lose power running on a rotary phase converter?

Absolutely not, provided the rotary phase converter is sized correctly. Our Micro-Smart controller generates a balanced three phase output allowing your equipment to furnish full rated power.

Will my utility company approve of an America Rotary Phase Converter?

Most utility companies will recommend the use of a rotary phase converter. In fact, it is much more cost favorable compared to installing 3-phase power lines. With the American Rotary/Baldor induction generator and American Rotary's Variable Impedence Technology (VIT), utility companies prefer the American Rotary converter because it use 1/3 of the current at start up compared to other phase converters.

Is there a US standards organization specifically for phase converters?

The truthful answer is no!”  The only organizations we are aware of and adhere to are UL (Underwriters Laboratories) and the N.E.C.(National Electric Code) Article 455. These are the organizations and standards that America Phase Converters follows.

Phase Converter Simple Installation

In this video, we show the basic installation techniques of the American Rotary Phase Converter Panel. The idea is to show how easy it is to install, and also to provide a video reference for our customers. The video is just under 4 minutes long.


Harold Rowlett, . / .
— Metal Working and Woodworking

Got the American Rotary AR7-UL 7.5 HP phase converter installed and it’s working like a charm. It was so easy to install and to wire. I have another American Rotary 3 HP converter that I purchased over 5 years ago and the improvements you have made to the new units have really simplified the Installation and wiring of the units. I have used the 3 HP unit without the first problem and fully expect the new one to perform just as well.  These are top notch units and I would recommend them to anyone.  They both are being used on metalworking and woodworking machines and are running flawlessly.  I have attached a couple of pictures to show how I installed the unit. As you can see in the pic we wall mounted the control box and we put the generator on the other side of the wall in an insulated compressor room. The only problem we had was not being able to hear the generator run which caused us to leave it running overnight a time or two. So I wired in a remote red light and mounted on wall above the control panel (you can see it “on” in the pic) so when we closed the shop we would see the red light on and remember to turn the unit off.


I want to thank you and the staff for being so pleasant to deal with and also the phone calls to follow up before and after the purchase to see if everything was working as it should. Not too many companies have that kind of service anymore. Rest assured if in the future I need more equipment it will be American Rotary.

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