Monitoring annunciator apparatus
US4774510A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 9, 1986 |
| Grant date | Sep 27, 1988 |
| Priority date | — |
| Expiry date | May 9, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B25/14
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A monitoring annunciator apparatus for monitoring the status of field contact points, which apparatus cooperates with one or more contact points utilizing a single signal wire for each monitored point and a ground wire common to all monitored points, so as to provide separate audible and visual indication, or alternative actuation of a response, upon the occurrence of a change in status of each monitored field contact point and indication of the occurrence of change in the integrity of each wire pair. A microprocessor driven circuit sequentially selects and connects each field contact point to be monitored and tests each field contact point and associated line means at varying voltages the results of which are transformed into a digital logic signal which the microprocessor converts into logic signals to generate audible and visual indication of the status of each of said contact points and associated wire pair on a display or otherwise command that action be taken towards returning said contact points and wire pairs to normal status.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.