Cathodic protection analyzer in which the fundamental and odd harmonics of a power line frequency are removed
US4940944A · kind A · utility
9Cited by
14References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 16, 1989 |
| Grant date | Jul 10, 1990 |
| Priority date | — |
| Expiry date | Feb 16, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R19/25
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An instrument for measuring cathodic protection voltage levels receives a signal representative of an externally applied, full-wave rectified power line frequency cathodic protection potential, which is subject to electrical interference. The fundamental power line frequency component and odd harmonics of that fundamental component are removed to produce a filtered signal. Selected parameters of the filtered signal are measured to provide an indication of the adequacy of the cathodic protection potential.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.