Power line meter/monitor with LED display
US6198403A · kind A · utility
Inventors
Key dates
| Filing date | Apr 7, 2000 |
| Grant date | Mar 6, 2001 |
| Priority date | — |
| Expiry date | Apr 7, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R19/2513
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In this micro-controller-based line voltage meter/monitor instrument, an AC signal-under-test is sensed from the line voltage via a broadband isolation transformer, and processed to provide RMS and fast peak signals. These are A/D converted in the micro-controller in a sampling process synchronized from a zero-cross signal detected from the AC voltage-under-test. An LED (light-emitting diode) display with 40 LED segments provides resolution of one volt RMS per LED step/segment, and is color-coded to overlay the CBEMA nominal limits. RMS values ranging from 95 to 135 volts are indicated on a bar graph, and fast peak values ranging from 120 to 500 volts at the waveform crest are indicated by the selected LED cell flashing at a 1 Hz rate, with selectable peak hold time. An internal real time calendar/clock enables accumulation of time-related data regarding the ongoing quality of the power line voltage levels. A variety of parameters and alarm limits can be configured by the user via a DIP switch and/or a user port, accessible at the rear of the instrument, by which the instrument can be connected in two-way communication with an external computer or control terminal, e.g. with a keyb…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.