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:
Aug. 01, 2000
Filed:
Mar. 05, 1998
Mark J Obermeier, Coventry, CT (US);
Paul H Singer, West Hartford, CT (US);
Michael R Koller, Plainville, CT (US);
General Electric Company, Schenectady, NY (US);
Abstract
A method of initializing short time and groundfault protection heat index accumulators to compensate for current flow during the time interval between the application of phase current and application of current measurement and protection algorithms in an electronic trip unit is presented. The electronic trip unit includes a microcontroller and associated ROM having trip unit application code, e.g., main functionality firmware, including initializing parameters, and boot code, stored therein and EEPROM having operational parameter code, e.g., encoded enumerations for parameters such as 50/60 Hz., UL/ANSI/IEC, etc., stored therein. The time internal comprises first and second time components. The first time component is the time between the instant phase currents are applied and the instant the microcontroller is initialized and the second time component is the time between the instant the microcontroller is initialized and the instant the microcontroller begins execution of short time and groundfault algorithms (i.e., protection algorithms). The first time component is approximated by applying an initial current measurement to index a calibrator. The second time component is measured by a counter controlled by the initialization firmware. The first and second time components are applied to the initial current measurement (or a derivative thereof) to determine an initial value (or a component thereof), for short time and/or groundfault heat index accumulators.