Method and apparatus for comparing load current in an electrical circuit with the capacity of its supply source
US5644238A · kind A · utility
Inventors
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | Jul 1, 1997 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R1/40
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and apparatus for measuring and recording peak RMS electrical current over multiple moving-average time periods provides current-flow information in the same units used to characterize electrical system distribution components--primarily overcurrent protective devices such as fuses and circuit breakers. Rather than reporting current-flow information based on a series of brief observations of a few line cycles or seconds, short duration RMS current-flow information in multiple geometrically increasing time intervals is calculated and accumulated to form longer duration RMS values of current. The resulting set of peak RMS current-flow values properly characterizes both the long and short term heating effects of the electrical current in the circuit under inspection, and is used in direct side-by-side comparisons with manufacturer provided data for specific distribution components in the evaluation of usage versus capacity and other functions relevant to distribution system design.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.