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:
Jul. 21, 2020
Filed:
Oct. 11, 2019
Cisco Technology, Inc., San Jose, CA (US);
Xiqun Zhu, Cupertino, CA (US);
Sung Kee Baek, San Ramon, CA (US);
Robert Gregory Twiss, Chapel Hill, NC (US);
CISCO TECHNOLOGY, INC., San Jose, CA (US);
Abstract
To reduce the rate at which a false alternating current ('AC') loss alarming signal is generated, but at the same time detect an actual AC loss situation in a timely manner, the disclosed method describes an AC line power loss detection and active verification method. If the AC line input voltage dips momentarily lower than a standard sine wave amplitude, the AC line may not be considered lost as long as it still has energy to drive a load. The method inserts a momentary load across the AC line and compares the AC line voltage before and after the extra load is applied. If the AC power is present, this extra loading will increase the AC loading current momentarily, but will not affect the AC line voltage. However, if the AC power is lost, such loading will lower the AC line voltage, indicating a loss of power.