Sequence of events detection in a process control system
US6760687B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 2001 |
| Grant date | Jul 6, 2004 |
| Priority date | — |
| Expiry date | May 14, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P90/02
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A sequence of events detection system for use in a process control system uses sequence of events detection cards to detect and store indications of events and the times at which these events take place within the process control network. The sequence of events reporting system includes a stable master time source that is used to periodically time synchronize secondary clocks within each of the nodes of the process control system. Free running counters are located within each of the sequence of events detection cards at each node and these free running counters are used to mark each event with a counter value when the sequence of events detection card first detects the event. Indications of the event and of the counter value associated with a detected event are sent from each of the sequence1 of events detection cards to a corresponding controller which uses its secondary clock, a further free running counter and the value of the sequence of events counter assigned to the event to ascertain the actual or absolute time that the event was detected at the sequence of events card. The event and the absolute time for that event is then sent to a sequence of events reporting database, wh…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.