Cathodic protection of structures
US4664764A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 4, 1986 |
| Grant date | May 12, 1987 |
| Priority date | — |
| Expiry date | Mar 4, 2006 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23F13/04
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Method, system and apparatus for carrying out the cathodic protection of structures wherein evaluation of true current and true voltages at the counter electrode is carried out by an integration procedure which is timed in conjunction with the cross-over times of the originating a.c. input to the power source. The system also may employ an IR drop free potential measurement of a variety employing a reference electrode and a control which periodically turns off the fluctuating current drive to the working electrode for purposes of carrying out potential measurement from the reference electrode. To improve performance of the system, as well as the true current measuring features, difference networks are used to develop the difference between the signals of one channel, i.e. ground, and the parallel channel, i.e. positive, leading to the working and reference electrodes. With the arrangement, spurious noise phenomena are cancelled. The system also employs a hierarchal control system which operates in conjunction with a soft start procedure functioning to enhance system reliability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.