An electric power meter is disclosed. The meter comprises means for digitally sampling voltage and current. The meter further comprises means for storing the digitally sampled voltage and current. The meter further comprises means for performing power calculations upon the digitally sampled voltage and...http://www.google.com.tw/patents/US20040122833?utm_source=gb-gplus-share專利 US20040122833 - Intelligent electronic device having network access
