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AUL - UL Listed Smart Series

The AUL Series rotary phase converters are designed for installations that require UL-certified electrical equipment while delivering reliable three-phase power from single-phase service.

Each AUL converter is UL Listed by Underwriters Laboratories, a globally recognized safety science organization that tests products against strict electrical safety standards. This certification provides confidence that the equipment meets recognized safety and compliance requirements for commercial and industrial installations.

The AUL Series also includes built-in surge protection to help protect equipment against lightning strikes, brownouts, and power surges.

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When to Choose the AUL Series

The AUL Series rotary phase converters are designed for installations where UL-listed electrical equipment is required to meet building codes, inspection requirements, or facility safety standards.

These converters provide the same reliable phase conversion performance while ensuring the electrical system complies with recognized safety and certification requirements.

The AUL Series provides dependable phase conversion while helping ensure electrical installations meet safety and compliance requirements.

For applications where UL certification is not required, the AR Pro(link), AD Digital(link), or ADX Smart Series(link) may offer suitable alternatives depending on the equipment and load requirements.

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AUL – UL Smart Phase Converter Models

Compare horsepower options to find the right UL-listed rotary phase converter for installations that require certified electrical safety compliance.

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Watch this quick guide on the 5 things you need to know before choosing a phase converter. It explains what matters, what to avoid, and how to make sure your equipment gets the right power.

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Our Advantages

Why Choose American Rotary
Phase Converters

Same-Day Shipping

Converters are built, tested, and stocked in our Wisconsin facility, then shipped the same day. You get the power you need without waiting weeks.

Proprietary Technology

Custom Baldor generator, digital MicroSmart™ control, CTR™ stabilization, and surge protection — technology you’ll only find at American Rotary.

Lifetime Warranty

Every converter is backed for life. You know we will support the unit as long as you own it.

Same-Day Replacement

If something does go wrong, we do not leave you stuck. We ship a replacement converter the same day so you can get back up and running.

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Customer stories

Real experiences from people who trust our products

My old rotary phase converter gave 30 years of faithful service before it went up in smoke. With customers asking when I’d be operational, I researched every manufacturer and the choice was clear on American Rotary. First impression when it ... READ MORE

FAA Certified Machine Shop Owner

  • Machining

Very good company to do business with. The salesman Lenny treated me like I was a big company. I was shopping for a roto phase for my home machine shop. He had all the time in the world for me. ... READ MORE

Rodney Mears

  • Machining

A quick google search pointed me toward American Rotary. It wasn’t their website or their pricing but the number of videos and testimonials about the quality of their product and the great service. I wasn’t disappointed. I called on a ... READ MORE

Carl DiPaolo

  • Machining

I purchased this unit for a tenant in a commercial property that needed 3 phase power and the cost for the utility company to bring it in was significantly higher with much longer times to complete the project. The phase ... READ MORE

Matt Peace

  • Metalworking

I tried an inexpensive digital converter that made my machine motors very hot due to unbalanced power. A person I bought a milling machine from said he had an American Rotary and was very happy with the quality, so I ... READ MORE

Brad Everett

  • Machining

When I started, the garage had a single 120 V receptacle behind a shelf. Now, there (4) duplex 120A receptacles, (1) NEMA 16,20 A 240/120V with a DPDT switch to select voltages. 30A 50A 1 phase receptacles. Two 20A, one ... READ MORE

Raymond Jensen

  • Agriculture

I called in a talked to a representative told them I have a refrigeration unit I was looking to run 3 phase to, gave them the specs and was recommended the ADX 10. I ordered it super fast shipping got ... READ MORE

Jonathan Arrington

  • Food Service

I had to move my workshop due to rent increases. The one I found didn’t have 3 phase. I found some cheap crappy digital shifter…didn’t work. Then I found American Rotary, they are the real deal! I am able to ... READ MORE

Mike Chinn

  • Woodworking

para todos los hispanohablantes America Rotary 100% recomendado fácil de instalar fácil de manejar fácil de cablear todo perfectamente gracias por su ayuda para poner en funcionamiento mi máquina edgebanding 3 Phase For all Spanish speakers, American Rotary 100% recommended. ... READ MORE

Neftaly Bustos Custom

  • Woodworking

Just got my ADX 5 up and running couldn’t be happier with my decision to purchase this excellent customer service and tech support. A++++++

... READ MORE

Mark Anderson

  • Metalworking

Absolutely love what american rotary does. Had a wonderful experience with their support team the phase converter we purchased and the transformer were supper easy to install definitely recommend buying from them. Customer service is 10/10

... READ MORE

Custom Machined Concepts | Andrey Girenko

  • Machining

American Rotary is an awesome company to work with, Mike was/is very helpful in answering my questions and getting me what I needed to get my shop ready for a new machine, giving me an option to either piggy back ... READ MORE

Charles Nelson

  • Machining

FAQs

Everything you need to know about getting the right power for your equipment.

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What is an AUL – UL Smart phase converter?
An AUL – UL Smart phase converter converts single-phase electrical power into balanced three-phase power while meeting UL safety certification standards for electrical equipment. The UL listing confirms the equipment has been tested and certified by Underwriters Laboratories for electrical safety and compliance.
A UL-listed phase converter has been tested and certified by Underwriters Laboratories (UL) to meet recognized electrical safety standards. Many commercial installations, government facilities, and regulated environments require UL-listed equipment to pass inspection and comply with electrical codes.
A UL-listed phase converter is often required when equipment must pass electrical inspection or when installations are subject to strict safety compliance. This may include commercial buildings, public facilities, manufacturing plants, and projects governed by local electrical codes.
AUL converters can power a wide range of three-phase equipment including CNC machines, pumps, compressors, machine tools, manufacturing equipment, and other industrial machinery.
AUL rotary phase converters are typically sized based on the horsepower of the largest motor in the system. Many installations follow a 2:1 sizing guideline to ensure sufficient starting capacity and stable operation.

American Rotary offers several phase converter series designed for different types of equipment and operating environments.
American Rotary offers several phase converter series designed for different types of equipment and operating environments.

  • AR Series  – General-purpose rotary phase converters for shop equipment and light industrial loads.
  • AD Series – Digital phase converters designed for voltage-sensitive equipment such as CNC machines, EDM systems, and VFD-driven machinery.
  • ADX Series – Extreme-duty phase converters built for high-inertia and hard-starting loads such as compressors, pumps, and heavy industrial machinery.
  • AI Series – Industrial-grade phase converters designed for outdoor environments and demanding agricultural or industrial applications.
  • AUL Series – UL-certified phase converters for installations requiring compliance with electrical safety standards.
Yes. AUL converters can operate multiple machines as long as the combined running load does not exceed the converter’s rated capacity.
AUL rotary phase converters generate a balanced third leg of power using an idler generator motor, allowing equipment to operate similarly to utility three-phase power.
No. AUL phase converters allow three-phase equipment to operate using single-phase electrical service, making them a practical solution when utility three-phase power is unavailable or too expensive to install.