Probe mapping diagnostic methods
US6559657B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 12, 1999 |
| Grant date | May 6, 2003 |
| Priority date | — |
| Expiry date | Jan 12, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S7/4078
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for processing a time domain reflectometry (TDR) signal having a plurality of reflection pulses to generate a valid output result corresponding to a process variable for a material in a vessel. The method includes the steps of determining a reference signal along a probe in the vessel, establishing a first fiducial reference point, a reference end of probe location, a measuring length and a maximum probe length. The method also includes the steps of periodically detecting a TDR signal along the probe, establishing a second fiducial reference point, a detected end of probe location, an end of probe peak to peak amplitude, and attempting to determine a process variable reflection on the TDR signal. The method indicates a broken cable condition, a loss of high frequency connection, a low amplitude reflection condition, an empty vessel condition. Distances and locations on the reference signal are computed in relation to the first fiducial reference point, and distances and locations on the TDR signal are computed in relation to the second fiducial reference point.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.