Protection circuit for avoiding using of an improper alternating current power source
US7570472B2 · kind B2 · utility
Assignees
Inventor
Key dates
| Filing date | Nov 28, 2005 |
| Grant date | Aug 4, 2009 |
| Priority date | — |
| Expiry date | Jun 6, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/319
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A protection circuit for avoiding the use of an improper alternating current source includes: a rectifier circuit; a voltage comparator circuit having a first input terminal, a second input terminal, and an output terminal; a sampler and filter circuit; an alarm circuit connected to the output terminal of the voltage comparator circuit; and a switch control circuit. The rectifier receives a voltage from an external AC power and outputs a single-direction pulsed voltage. The sampler and filter circuit includes an input terminal connected to an output terminal of the rectifier circuit, and an output terminal connected to the first input terminal of the voltage comparator circuit. The switch control circuit enabled or disenabled by means of a control signal received from the voltage comparator circuit. One of the input terminals of the voltage comparator circuit accepts a constant reference voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.