Location History:
- Glucester, CA (1993)
- Gloucester, CA (1985 - 1999)
- Ottawa, CA (1981 - 2004)
Company Filing History:
8 out of 1,012 
3 out of 424 
2 out of 45 Years Active: 1981-2004
Title: The Innovations of Eddy So
Introduction
Eddy So is a prominent inventor based in Gloucester, CA, known for his significant contributions to the field of electrical engineering. With a total of 14 patents to his name, he has developed innovative technologies that enhance measurement accuracy in electrical applications.
Latest Patents
Eddy So's latest patents include a current-comparator-based four-terminal resistance bridge for power frequencies. This invention utilizes a current comparator technique to achieve highly accurate AC resistance measurements at power frequencies ranging from 50 Hz to 60 Hz. The bridge is designed to measure resistances from 10 µΩ to 100 kµΩ, featuring a cascading technique that extends the ratio range to 100,000,000 with a maximum applied current of 10,000 A. The measurement resolution is impressive, with a total combined uncertainty estimated to be less than 5 µΩ/Ω.
Another notable patent is the current ratio device for use in forming a current transformer. This device is designed as a hand-held, openable-core clamp-on type of current transformer. It employs electronically-aided three-stage circuitry to enable accurate low current measurements across a wide operational range. This transformer is particularly suited for use with highly accurate active/reactive power and energy meters, as well as harmonic power analyzers. It can measure currents ranging from 1 A to 200 A with ratio errors of less than 50×10⁻⁶ for both in-phase and quadrature components.
Career Highlights
Eddy So has worked with esteemed organizations such as the National Research Council of Canada and Canadian Patents & Development Ltd. His work in these institutions has allowed him to refine his skills and contribute to groundbreaking advancements in electrical measurement technologies.
Collaborations
Throughout his career, Eddy has collaborated with notable individuals, including William J. Moore and David A. Bennett. These partnerships have fostered innovation and have led to the development of several of his patents.
Conclusion
Eddy So's contributions to electrical engineering through his patents and collaborations highlight his role as a significant inventor in the field. His innovative solutions continue to impact the accuracy of electrical measurements, showcasing his dedication to advancing technology.