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:
Oct. 31, 2000
Filed:
May. 09, 1997
Scott T Holdsclaw, Raleigh, NC (US);
Rodney C Hemminger, Raleigh, NC (US);
ABB Power T&D Company Inc., Raleigh, NC (US);
Abstract
A 2-element, three voltage connection electronic energy meter is disclosed for measuring 3-phase electrical energy supplied by a 4-wire delta service without external potential transformers. The meter employs non-isolating voltage sensors for sensing the line voltages and includes and an automatic service type detector and isolation detector. The meter generates voltage and phase angle measurements for each of the two voltages sensed by the meter. The service type detector compares the phase angles to automatically determine the service type supplying the electrical energy to the meter. The isolation detector compares the two voltages to automatically determine whether or not the installation includes external potential transformers. If the service type is a 4-wire delta service and no external potential transformers are used at the installation for isolating the voltage signals, the meter doubles the voltage measured over the first of the two elements when generating power measurements.