Power distribution unit with individual GFI modules and a line supervisory circuit
US5894392A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 18, 1997 |
| Grant date | Apr 13, 1999 |
| Priority date | — |
| Expiry date | Aug 18, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/338
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A power distribution unit for supplying temporary branch power has a 240-250 VAC input with input power line conductors L1 and L2, a neutral conductor N, and a ground conductor G. A supervisory circuit checks that the 240-250 VAC input is properly connected to the power distribution unit by requiring that the input voltage exceeds a supervisory circuit threshold voltage substantially greater than 120-125 volts. When that occurs, a contactor is enabled by the supervisory circuit to close first and second contacts therein to pass the 240-250 VAC on lines L1 and L2 therethrough to a 240-250 VAC ground fault interrupter protected circuit breaker outlet. A plurality of 120-125 VAC GFI module outlets are connected across either one of lines L1 and L2 at the output of the supervisory circuit and the neutral conductor N which bypasses the contactor. The supervisory circuit includes a diode bridge circuit connected across power line conductors L1 and L2 to convert a 240-250 VAC input to 240-250 VDC. A voltage threshold zener diode is connected in series with first and second relays across the 240-250 VDC, such that the zener diode ensures that the voltage required to operate the first and s…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.