Electrical extension cord with built-in safety protection
US5642248A · kind A · utility
Inventors
Key dates
| Filing date | Aug 31, 1995 |
| Grant date | Jun 24, 1997 |
| Priority date | — |
| Expiry date | Aug 31, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/33
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electrical extension cord with built-in safety protection includes an electrical cable formed with insulated phase, neutral and ground conductors surrounded by a braided sensing shield. An electrical receptacle is electrically connected to the cable at first ends of each of the phase, neutral and ground conductors, and the shield is electrically connected to the ground conductor. A ground fault circuit interrupter (GFCI) is electrically connected to the cable at second ends of the phase, neutral and ground conductors, within which the ground conductor is electrically coupled to the shield through a predetermined impedance such that leakage current is collected by the shield and detected by the GFCI.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.