Issued Patents All Time
Showing 1–23 of 23 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7595614 | Load tap changer | James H. Harlow, William F. Griesacker, Reshma Sharif | 2009-09-29 |
| 6266260 | Inverter having center switch and uninterruptible power supply implementing same | Donald K. Zahrte, Sr., David L. Layden, Douglas C. Folts | 2001-07-24 |
| 5790391 | Standby power system | Peter William Jungwirth, Donald K. Zahrte, Sr. | 1998-08-04 |
| 5729120 | Dynamic voltage regulation stabilization for AC power supply systems | Donald K. Zahrte, Sr., Gregory C. Kohls, Robert R. Davidson | 1998-03-17 |
| 5615129 | Method and apparatus for adaptive and corrective determination of battery run-time in uninterruptible power systems | Thomas Hubert, Timothy Walsh | 1997-03-25 |
| 5602462 | Uninterruptible power system | Thomas Hubert, David L. Layden, Donald K. Zahrte, Sr. | 1997-02-11 |
| 5315533 | Back-up uninterruptible power system | Donald K. Zahrte, Sr., Richard V. Baxter, Jr., Douglas C. Folts, Thomas Hubert, Juan Manuel Medina +2 more | 1994-05-24 |
| 5295078 | Method and apparatus for determination of battery run-time in uninterruptible power system | Edward G. Beistle | 1994-03-15 |
| 5229651 | Method and apparatus for line power monitoring for uninterruptible power supplies | Richard V. Baxter, Jr. | 1993-07-20 |
| 5182518 | Inverter and battery testing for uninterruptible power systems | Richard V. Baxter, Jr., Herbert A. Podewils, David L. Layden | 1993-01-26 |
| 5160832 | Front panel unit for electronic equipment | Thomas Hubert, William J. Hazen, Ricky Linn Mills | 1992-11-03 |
| 4659973 | Brushless exciter for controlling excitation of a synchronous machine | — | 1987-04-21 |
| 4622513 | Gating of the thyristors in an arcless tap changing regulator | — | 1986-11-11 |
| 4539618 | Digitally controlled overload relay | — | 1985-09-03 |
| 4516185 | Time ratio control circuit for contactor or the like | John C. Culligan, Conrad F. Williams | 1985-05-07 |
| 4456871 | Power supply for electronic control system | — | 1984-06-26 |
| 4446498 | Electronic control system for overload relay or the like | — | 1984-05-01 |
| 4423458 | Signal processing system for overload relay or the like | — | 1983-12-27 |
| 4423459 | Solid state circuit protection system and method | Conrad F. Williams | 1983-12-27 |
| 4404442 | Circuit interrupter having flash plates with interrupted surfaces | John D. Kleinecke, Roger L. Robertson | 1983-09-13 |
| 4378580 | Conduction limit protection arrangement for power transistor switch | — | 1983-03-29 |
| 4363060 | Arcless tap changer for voltage regulator | — | 1982-12-07 |
| 4301489 | Arcless tap changer utilizing static switching | — | 1981-11-17 |