Technical Support
U.S. Patents — Phoenix Phase Converters
Phoenix Phase Converter Patents
Phoenix Phase Converters has been awarded three U.S. patents on rotary phase conversion technology — covering inrush-current reduction, variable-frequency soft-start, and automatic single-phase-to-three-phase startup on load detection. This page identifies the patents covering each product line, in accordance with 35 U.S.C. § 287(a), the federal virtual patent marking statute.
3
U.S. patents granted
2016–2021
Grant date range
2036–2041
Expiration range
1
Wikipedia citation
Virtual patent marking notice: The products listed on this page are marked with the words "patent" or "patented" together with a reference to this web address (phoenixphaseconverters.com/pages/patents). This page provides constructive notice to the public of the patents associated with each product, as authorized by 35 U.S.C. § 287(a).
Granted U.S. Patents
U.S. Patent 9,484,844 B1
Circuit and method for reducing inrush current of phase converter motor
A circuit and method for soft-starting the idler motor of a rotary phase converter so that line-side inrush current is dramatically reduced. The same circuit lets a Phoenix AutoStart unit stop and restart the idler repeatedly across a working day without damaging itself, which is the foundation of the AutoStart energy-saving product line.
View on Google Patents → · Cited on Wikipedia
U.S. Patent 9,692,326 B2
Circuit and method for reducing inrush current of a three phase motor
A method that starts a three-phase motor by first supplying low-frequency three-phase alternating current and gradually ramping the frequency up to operating speed before switching the motor onto steady-state three-phase power. This variable-frequency soft-start approach reduces inrush current across a much wider range of motor sizes than the original circuit alone.
View on Google Patents →
U.S. Patent 11,050,379 B1
Circuit and method for start of single phase to three phase conversion system
A converter circuit and operating method that automatically starts the phase conversion system the moment a three-phase load demands power, and disconnects when the load goes away. This is the patented load-sensing logic behind Phoenix's AutoLink and zero-standby AutoStart variants — the converter only spins when your machine is calling for power.
View on Google Patents →
Product-to-Patent Listing
| Product line | Covered by U.S. Patent(s) |
|---|---|
| AutoStart series (all HP tiers, including transformer-equipped variants) |
9,484,844 ·
9,692,326 ·
11,050,379
|
| AutoLink series (automatic load-sensing start) |
11,050,379
|
| DualZone series (staged dual-idler configurations) |
9,484,844 ·
9,692,326
|
| Standard rotary series (continuous-run configurations) |
9,484,844 ·
9,692,326
|
This page is updated as additional patents are granted or as product configurations change. Patent applications currently pending examination by the U.S. Patent and Trademark Office may be added to this list once a patent number is issued.
About Our Patented Engineering
Why a patent matters in this category
Most rotary phase converters on the market are engineered around the same general topology. What separates a long-life Phoenix unit from a generic rebrand is the soft-start sequence — the moment the idler motor first spins up — and the load-detection logic that decides whether the idler should be running at all.
The first two patents above (9,484,844 and 9,692,326) protect the circuit and method that solve the inrush-current problem. They are what let a Phoenix 20 HP rotary start on a 60 A single-phase service when a generic 20 HP rotary typically needs 100 A or more, and what allow AutoStart to repeatedly start and stop the idler motor across an 8-hour workday without progressively damaging itself.
The third patent (11,050,379) protects the automatic load-detection startup — the converter wakes up the instant your machine needs power, and shuts down when it doesn't. That is the engineering behind AutoLink and the zero-standby behavior of the AutoStart product line.
Inventor
Glen Floreancig is the named inventor on all three granted U.S. patents above and continues to lead Phoenix's engineering program on rotary phase converter technology. Glen's published work on the patented inrush-current circuit is cited on the Wikipedia entry for phase converters.
Third-party recognition
Phoenix Phase Converters was recognized by Electrical Business Review as one of the Top 10 Power Converter Solutions Providers of 2025. Glen and Daniel Floreancig were also featured in VoyagePhoenix and CanvasRebel Magazine on the engineering work behind this patent portfolio.
Patent Licensing & Inquiries
The patents listed on this page are owned by Glen Floreancig and/or Applied Industrial Motors, LLC, doing business as Phoenix Phase Converters. For licensing inquiries, please contact the factory at phoenixphaseconverters@gmail.com or call (800) 417-6568.
Legal notice: The information on this page is provided in good faith and is intended to comply with the marking requirements of 35 U.S.C. § 287(a). Listings on this page may be added, removed, or modified at any time as patents are issued, expire, or are reassigned. This page does not grant any license, express or implied, to any Phoenix Phase Converter patent. Unauthorized practice of the claimed inventions is prohibited.
Talk to the Inventor
Sizing questions, patent licensing inquiries, or engineering review — call the factory and you talk to Glen.
Call (800) 417-6568Talk to a Phase Converter Engineer
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