Ground fault detection circuit
US4542432A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 1982 |
| Grant date | Sep 17, 1985 |
| Priority date | — |
| Expiry date | Aug 27, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/33
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A current monitoring circuit of a ground fault detector which receives its input from the secondary winding of an annular core transformer through which extends the current carrying leads being monitored. A resistor and capacitor are connected in series between the secondary winding and an AC amplifier to form an RLC band pass filter to minimize the circuits sensitivity to noise outside of the band of frequencies of interest. The sensitivity of the circuit to temperature changes due to fluctuations of the inductance is reduced by choosing an inductance value sufficiently high to ensure that it is not reduced to below a critical level at which sensitivity is effected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.