Graphical interfaces for monitoring ladder logic programs
US5321829A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 20, 1990 |
| Grant date | Jun 14, 1994 |
| Priority date | — |
| Expiry date | Jul 20, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S715/97
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A menu-driven system for developing Man-Machine Interfaces (MMI) for use in the graphical monitoring of ladder logic programs executing in programmable logic controllers PLCs. The Man-Machine Interfaces graphically depict plant processes controlled by the PLC. Data from the PLC representing plant process events (flows, state changes, tank levels, etc.) are communicated to the Man-Machine Interfaces. A Development System provides a programmer's "tool box" for constructing the Man-Machine Interfaces. Ladder logic programs and databases associated therewith are imported and accessed by the Development System for use in the development of the Man-Machine Interfaces. A Runtime System provides an execution environment for the Man-Machine Interfaces. The Runtime System has the ability to access ladder logic programs during monitoring operations. A user can "hot-key" to the ladder logic program for trouble-shooting purposes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.