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:
Dec. 28, 2010
Filed:
Sep. 12, 2008
Roy Ball, Coral Springs, FL (US);
Russ Gonnam, Coral Springs, FL (US);
Cristine Luong, Coral Springs, FL (US);
Roy Ball, Coral Springs, FL (US);
Russ Gonnam, Coral Springs, FL (US);
Cristine Luong, Coral Springs, FL (US);
ABB Technology AG, Zurich, CH;
Abstract
A test plug for use with protective relays has a circuit that when it detects an overvoltage on the secondary side of a current transformer limits the overvoltage amplitude and the occurrence of the overvoltage to a predetermined number of peaks that are less than all of the peaks that occur when the secondary side is open circuited and the test plug is connected to the relays. The test plug also ensures that there is a continuous flow of current in the relays. The test plug further that has an indicator visible external to the plug to indicate the occurrence of an open circuit transformer secondary and that indicator remains illuminated when the test plug is disconnected from the protective relays.