Insulation resistance drop detector and method of detecting state thereof
US7005860B2 · kind B2 · utility
9Cited by
1References
7Claims
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Key dates
| Filing date | Oct 7, 2004 |
| Grant date | Feb 28, 2006 |
| Priority date | — |
| Expiry date | Oct 7, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/52
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An insulation resistance drop detector 50 and a method of detecting a state of malfunction of the detector 50 are provided. When open of a coupling capacitor Co or malfunction of a lowpass filter 53 is occurred, a time constant of the low pass filter 53 is decreased and a rising time of an output of the lowpass filter 53 against an output of a pulse signal P1 becomes shorter than that in a state of normal. Thereby, malfunction of the detector 50 can be detected based on the output of the filter 53 corresponding to change of frequency of the pulse signal P1.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.