The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 13, 1999
Filed:
Aug. 18, 1997
Thomas M McDonald, Monroe, CT (US);
Hubbell Incorporated, Orange, CT (US);
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 second relays is substantially greater than 120-125 VDC. The first relay operates contacts to activate the contactor, and the second relay operates contacts to bypass the neutral conductor N around the contactor.