Fault detection system
US6867596B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 23, 2003 |
| Grant date | Mar 15, 2005 |
| Priority date | — |
| Expiry date | Jan 23, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/083
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A system and method for fault detection including a transmitter adapted to transmit a composite signal on a buried cable so that fault leakage of the composite signal returns to the transmitter through the ground surrounding the buried cable. The composite signal is composed of a low frequency first component that alternates at a first frequency and that defines a phase, and a low frequency second component that alternates at a second frequency higher than the first frequency and that defines a duty cycle having a predetermined relationship with the phase of the first component. A receiver receives the composite signal from the probe and filters the first component, filters the second component, defines an alternating reference signal having a phase based on the duty cycle of the filtered second component, and compares the phase of the reference signal with the phase of the filtered first component.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.