Automatic monitoring of high voltage signals
US6385547B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 22, 1999 |
| Grant date | May 7, 2002 |
| Priority date | — |
| Expiry date | Sep 22, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R19/16571
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A pair of terminals across a voltage to be monitored includes, in series, a resistor for developing a low voltage proportional to the high voltage to be monitored, a resistor to develop a voltage indicative of an over-current condition, and a resistance comprising a plurality of resistors which are connectable in parallel with one another, automatically, by remotely actuated switches. When the monitoring system is turned off, the resistances are all automatically set to maximum to minimize the loading on the elevator system. When the monitoring system is first turned on, a preconfiguration routine determines the correct resistance value as that which is the lowest resistance value for which an overcurrent condition does not occur, and this preconfiguration resistance value is stored for future use. Upon subsequent turn on of the monitoring system, all of the resistance values are set at the values determined during the preconfiguration routine. During normal monitoring, an overcurrent condition (that is an output from the sensor responding to the overcurrent resistor) will increase the series resistance by one increment, store the new setting for future use and provide an alarm mes…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.