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. 11, 1983
Filed:
Dec. 04, 1981
Applicant:
Inventors:
Nils Brandt, Vasteras, SE;
Torbjorn Einarsson, Vasteras, SE;
Assignee:
Asea Aktiebolag, Vasteras, SE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H02H / ;
U.S. Cl.
CPC ...
361 87 ; 361 93 ; 361113 ;
Abstract
The present invention relates to a protection device for detecting at least one faulty phase in an electrical network. The device comprises a band exclusion filter for each phase for filtering away the signals which have the same frequency as the nominal frequency of the network, amplifiers, rectifiers and peak value forming means for each phase. In addition, the different phase signals are fed to a function element which delivers a signal to a level and comparison device for each phase, where the signal is compared with the signals in the respective phase.